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Multilayer ceramic pcb substrate manufacturing process: HTCC and LTCC technology

Multilayer ceramic substrate is also known as ceramic shell, ceramic tube shell. At present, most of the multilayer ceramic substrates are manufactured using co-fired ceramic technology – high-temperature co-fired ceramic technology (HTCC), low-temperature co-fired ceramic technology (LTCC) to achieve the mainstream of large-scale manufacturing of multilayer ceramic substrates.

In this article, we will focus on analyzing the advantages and applications of HTCC and LTCC two processes, to facilitate the selection of manufacturing processes that have a clearer direction. Details are as follows:

What is HTCC?

HTCC (High Temperature co-fired Ceramic), using materials such as tungsten, molybdenum, molybdenum, manganese and other high melting point metal heating resistor paste in accordance with the requirements of the heating circuit design printed on 92 ~ 96% of the alumina cast ceramic billet, 4 ~ 8% sintering additives, and then multi-layer stacked, at a high temperature of 1,500 ~ 1,600 ℃ co-fired into one. The product is co-fired under 1500~1600℃.

Therefore, it has the advantages of corrosion resistance, high temperature resistance, long service life, high efficiency and energy saving, uniform temperature, good thermal conductivity, fast thermal compensation, etc. Moreover, it does not contain lead, cadmium, mercury, hexavalent chromium, polybrominated biphenyls (PBBs), polybrominated diphenyl ethers (PBDEs), and other hazardous substances, and it complies with the environmental protection requirements of the European Union, such as RoHS.

Due to the high firing temperature, HTCC cannot use low melting point metal materials such as gold, silver, copper, etc. Refractory metal materials such as tungsten, molybdenum, manganese, etc. must be used, and the low electrical conductivity of these materials will cause defects such as delayed signals, and therefore they are not suitable for making the substrate of high-speed or high-frequency microassembly circuits. However, HTCC substrates have a wide range of applications in high-power microassembly circuits due to their advantages of high structural strength, high thermal conductivity, good chemical stability and high wiring density.

What is LTCC?

Low Temperature Co-fired Ceramic technology LTCC (Low Temperature Co-fired Ceramic) is a low-temperature sintered ceramic powder made of raw ceramic tape with precise thickness and density, in the raw ceramic tape using laser perforation, microvia slurry injection, precision conductor paste printing and other processes to make the required circuit graphics, and a number of passive components (e.g., low-tolerance capacitors, resistors, filters.), impedance converters, couplers, etc. buried in a multilayer ceramic substrate, and then stacked together, Impedance converter, coupler, etc.) buried in a multilayer ceramic substrate, and then stacked together, the inner and outer electrodes can be used respectively silver, copper, gold and other metals, sintered at 900 ℃, made of three-dimensional space does not interfere with each other’s high-density circuits, but also made of built-in passive components of the three-dimensional circuit substrate, the surface of which can be mounted on the IC and active devices, made of passive/active integrated functional modules, can be further circuit This makes it possible to further miniaturize circuits and increase density, and is particularly suitable for high-frequency communication components.

LTCC integrated components include a variety of substrates carrying or embedded in a variety of active or passive components of the product, integrated components product program includes components, substrates and modules.

HTCC technology vs LTCC technology

 

High temperature co-fired ceramic technology

▶Insulating materials: alumina, aluminum nitride, oxide plating, etc.
▶Conductor material: tungsten, platinum, platinum-manganese, etc.
▶Co-firing temperature: higher than 1400℃
▶Advantages: high mechanical strength, high thermal conductivity, low material cost, chemically stable.
▶Disadvantages: high on-resistance, high manufacturing cost

Low temperature co-fired ceramic technology

▶Insulating materials: microcrystalline glass, ceramic + glass composite system, amorphous glass, etc.
▶Conductor materials: gold, silver, copper, vantage – silver, etc.
▶Co-firing temperature: below 900°C
▶Advantages: low on-resistance, low manufacturing cost, low coefficient of thermal expansion, low dielectric constant and easy to adjust, can be buried passive devices, high-frequency characteristics are excellent, and can be produced with a line width of as low as 50 um of fine circuits.
▶Disadvantages: low mechanical strength, low thermal conductivity, high material cost.

Technology Benefits

Advantages of HTCC technology

HTCC because of the use of tungsten, platinum, and other high melting point metals, these metals greatly increase the RF loss of the component. The advantages are high structural strength, good chemical stability and high wiring density, and its thermal conductivity is as high as 20W/mK, which is far greater than the thermal efficiency of LTCC substrate. In contrast, the thermal conductivity of LTCC substrate is only 3W/mK, which makes it difficult to dissipate heat in the structure of high-density boards and easily makes the chip damaged.

Advantages of LTCC technology

(1) has good electrical and mechanical properties, such as high frequency characteristics, good temperature stability of the resonant frequency, the dielectric constant covers a wide range, the coefficient of thermal expansion is close to silicon.

(2) Has high system stability and reliability.

(3)Can produce 3D microstructures including cavities and channels.

(4)Possesses high level of integration characteristics (sensors, drivers, microfluidic control, electronic and optoelectronic systems for LTCC, etc.) ;and

(5) Very good characteristics at high voltage.

(6) High voltage characteristics and high vacuum. In addition, LTCC manufacturing industry is simple, fast and inexpensive, with low capital investment, short cycle time and high profitability.

Application of HTCC technology

High-temperature co-fired ceramic products mainly include ceramic multilayer substrates, ceramic packaging shells, UVLED brackets, VCSEL brackets, various types of heating pads, thermal bridges, etc., which are mainly used in microwave device packaging, large-scale integrated circuit packaging, hybrid integrated circuit packaging, optoelectronic device packaging, SMD packaging, LED chip packaging, semiconductor packaging and other packaging fields. HTCC ceramic substrate can be sintered with metal materials such as deforestation alloy to make HTCC package shell, which greatly saves the wiring space.

Application of LTCC technology

LTCC products have a wide range of applications, such as various types of cell phones, Bluetooth modules, GPS, PDA, digital cameras, WLAN, automotive electronics, optical drives and so on. Among them, the use of cell phones occupies the main part, about 80% above; followed by Bluetooth module and WLAN. due to the high reliability of LTCC products, the application in automotive electronics is also rising. LTCC products used in cell phones include LC filters, duplexers, function modules, transceiver switching function modules, balanced-unbalanced converters, couplers, power dividers, common mode chokes and so on.

What do you know about the classification of Bluetooth modules

Bluetooth module, is a kind of PCBA board with integrated Bluetooth function, used for short distance wireless communication. According to the function, it is divided into Bluetooth data module and Bluetooth voice module. Bluetooth module refers to the integrated bluetooth function of the chip basic circuit collection, used for wireless network communication, can be roughly divided into three types: data transmission module, bluetooth audio module, bluetooth audio+ data two-in-one module and so on. The general module has the property of semi-finished product, which is processed on the basis of the chip to make the subsequent application more simple.

This article is from the different classification of Bluetooth modules to sort out the type of Bluetooth module, as far as possible from the classification point of view to understand the Bluetooth module has some features and functions.

1.Categorized by protocol type

(1) Classic Bluetooth module

Classic Bluetooth module (BT) refers to Bluetooth protocol support 4.0 or less modules can be subdivided into: traditional Bluetooth module and high-speed Bluetooth module.

Traditional bluetooth module: bluetooth was born at the beginning, the use of BR basic rate technology, the bluetooth theoretical transmission rate, can only reach 721.2Kbps, launched in 2004 to support the bluetooth 2.0 protocol module, the outbreak of the smartphone era, the new EDR bluetooth enhancement rate (Enhanced Data Rate) technology, by improving the multitasking and a variety of bluetooth By improving multitasking and the ability of multiple Bluetooth devices to operate simultaneously, it enables Bluetooth devices to transmit at rates up to 3Mbps, which is three times the transmission rate of Bluetooth 1.2 technology. As a result, in addition to more stable audio streaming and lower power consumption, you can take full advantage of bandwidth to connect multiple Bluetooth devices at the same time.

High-speed Bluetooth module: High-speed Bluetooth module was launched in 2009, the main representative is to support the Bluetooth 3.0 protocol module, the new High Speed technology, you can make Bluetooth call 802.11 WiFi used to achieve high-speed data transmission, the transmission rate of up to 24Mbps, is the traditional Bluetooth module of 8 times.

Classic Bluetooth module is generally used for continuous streaming of audio and data volume is relatively large transmission, such as voice, music, wireless headphones, file transfer between devices, printers, wireless speakers and so on.

 

(2) Bluetooth Low Power Module

LowPower Module (BLE) means a module that supports the 2010 launch of Bluetooth Protocol 4.0 or higher . The biggest feature is the reduction in cost and power consumption . Bluetooth low-power technology uses variable connection time intervals. The interval can be set according to the specific application for a few milliseconds to a few seconds ranging from BLE technology using a very fast connection, so it can be in the “non-connection” state (energy saving), when the connection between the two ends of the link is only necessary to open the link, and then close the link in the shortest possible time. Then the link is closed in the shortest possible time.

Low-power Bluetooth is used in real time. Requirements are relatively high, but low speed, low power consumption of the scene, such as mouse and keyboard, heart rate detectors and thermometers and other sensor devices, smart home, smart wear such as the need for large amounts of data interaction in scenarios, is very suitable for Internet of Things applications.

To sum up, classic Bluetooth is not an outdated version of BLE. Classic Bluetooth and low-power Bluetooth coexist and are used in different applications, which completely depend on the different needs of each person.

2.Categorized by support for protocols

According to the number of Bluetooth protocol stack support can be divided into single-mode module and dual-mode module. The concept of single mode and dual mode is only available after the emergence of BLE Bluetooth. We should choose the required module according to cost, application and function.

 

(1) Single mode module

Single mode module is the module that supports a certain Bluetooth protocol, only the classic Bluetooth (BT) protocol or Bluetooth Low Power (BLE) protocol.

 

(2) Dual mode module

Dual-mode modules are modules that support both the classic Bluetooth (BT) protocol and the low-power Bluetooth (BLE) protocol, and can run two sets of protocol stacks. There are two types of dual-mode modules: Classic Bluetooth (data only)+ BLE and Classic Bluetooth (data+ audio)+ BLE. Dual-mode modules have good flexibility and compatibility.

Bluetooth dual mode is undoubtedly the mainstream of the future. Classic Bluetooth power consumption, 4.0 after Bluetooth BLE, power consumption is small, but does not support the audio protocol and due to data transmission speed limitations, Bluetooth dual mode is a combination of the advantages and disadvantages of the two, can support both audio transmission, can also support data transmission, low power consumption, and compatibility is the sum of the two.

3.Categorized by function

Standing in the Bluetooth module to transmit the size of of the functional point of view content, can be divided into the following categories.

(1) Data module

The general use of more data modules, i.e. Bluetooth low power, also known as Bluetooth transmission module. Because the amount of data is not large, the transmission of proximity, operation and standby power consumption has strict requirements for the device is a good choice. Due to the advantages of power consumption, Bluetooth 4.0 module has now occupied most of the share of mobile data transmission, and the size and share is expected to continue to grow.

(2) Audio Module

The audio module requires a very large bit of streaming data, so it is more suitable for the classic Bluetooth module.

(3) Composite data and audio modules

It can transmit voice, audio and data at the same time. Under the trend of mobile Internet, data+ audio application, the dual mode module with data and audio composite is a good choice.2\According to the protocol support points

4. According to the chip design classification

This is differentiated according to the type of storage used by the Bluetooth chip in the module.

(1) ROM version

In general, the chip manufacturer’s ROM version of the chip, characterised by the chip manufacturer, will be the standard application PROFILES cured in the chip. Usually a fixed function, the user can not modify the program in the chip. Can be connected to an external EEPROM, storage space is small, can be used to store Bluetooth address, device name, PIN code , etc.

Use the ROM version of the chip to do less differentiation of the product, but the development is simple. For some conventional products, they do not need deep customization of the product. The choice of ROM version of the chip can be developed to speed up the development progress, speed up the time to market. Suitable for large-scale mass production, the price is very low, more commonly used for dongles, Bluetooth headset modules, cell phone modules, mouse and keyboard modules, etc., can modify the configuration parameters, but the basic function is fixed. Large-scale civilian products generally use the ROM version of the module, such as USB Bluetooth adapters on the market, because most of the protocol will run inside the PC. The chip processing power requirements are very low, so the chip manufacturer will launch very low-priced products.

(2) FLASH version

Chips are generally built-in FLASH, storage space is large. If you want to do some customer-defined products, such as the need to add some sensors, communication with external MCU, increase Bluetooth protocol or service, you need to use the FLASH version of the chip in the FLASH version of the existing project to add their own engineering code, develop their own firmware, to make a differentiated product. Relatively speaking , it is more flexible.

FLASH version of the chip price is high, but the user can be carried out according to their own application needs, due to the chip built-in FLASH storage, the performance of its performance, while built-in audio codec circuitry, suitable for a variety of voice gateway and other applications. Industrial Bluetooth applications should generally use the FLASH version of the chip produced by the module, fast running, with high integration, high reliability, high performance indicators and other characteristics.

(3) EXT version

EXT module chip without FLASH memory, the need to expand the memory device, the user can carry out application development, characterized by moderate prices, shortcomings are stability, power consumption and other performance differences, while most EXT chip does not have audio decoding circuits, such as the need to realizeio transmission needs to be connected to an external codec device.

5. Classification according to power

In terms of power, there is a difference between low-power Bluetooth and classic Bluetooth.

Low power Bluetooth has no power level, the transmission distance can be more than 100m, 5.0 protocol distance even up to 300m, the specific distance depends on the product design power. The modulation of Bluetooth Low Power technology is slightly different from traditional Bluetooth technology. This different modulation uses a 10mwdb wireless chipset (Low Power Bluetooth’s maximum power) to achieve a connection range of up to 300m, which means that the entire range of homes and buildings can be covered, achieving a more robust and reliable connection.

Classic Bluetooth has three levels of power, expressed in Class. According to the Bluetooth specification, Class is not used to specify distance, but to indicate transmit power. Bluetooth module transmit power parameters are determined, the actual transmit efficiency and RF circuit, antenna efficiency related to the Bluetooth module communication distance and transmit power, reception sensitivity and application environment is closely related to Bluetooth work in the 2.4G band, penetration capacity is poor, in the case of blocking, should be in the actual field to test the communication effect. The purpose of power control is to control the radiation within the limits without interfering with the normal operation of neighboring Bluetooth devices, using the link management protocol to realize the power control algorithm between master and slave devices.

(1) Class 1

Class 1 output power of 1mW (0dBm) to 100mW (20dBm), support for 100m transmission distance, in order to achieve the maximum range, power control is mandatory. Class 1 is used in high-power, long-distance Bluetooth products, but because of the high cost and high power consumption, it is not suitable for cooperation with personal communication products (cell phones, Bluetooth headsets, Bluetooth Dongle, etc.), so it is mostly used in long-distance transmission.

Generally, few people will use long-distance transmission, but if you want to transmit audio over a long distance, connect audio over a long distance, and more commonly in some large-scale venues, stages, and industrial scenarios, using a Bluetooth adapter that supports Class 1 is the best solution.

(2) Class 2

Class 2 output power of 0.25mW (-6dBm) to 2.5mW (4dBm), power control is optional, under normal circumstances 1mW (0dBm) supports 10m transmission distance, as long as the transmitter power can exceed 0dBm is part of the scope of Class 2, but if more than 4dBm, then it is Class 1.

Most of the common Bluetooth devices on the market today are power consumption Class 2, mostly used in cell phones, Bluetooth headsets, Bluetooth Dongle personal communication products, power consumption and smaller size, while easy to carry.

(3) Class 3

Class 3 output power ≤ 1mW (0dBm), support 1m transmission distance. With the lowest output power, Class 3 devices are not common due to their very limited range of coverage.

6. Classification according to the support temperature

(1) Commercial grade

The temperature range is about 0℃~70℃. Generally used in ordinary consumer products, more common in life and lower prices are cheaper. Suitable for environmental conditions (such as temperature, EMC and mechanical stress) at a mild to moderate level in consumer product applications. Such as a variety of consumer electronics, smart home appliances, entertainment devices, mobile computing, cameras, monitors, routers and test equipment.

(2) Industrial Grade

The temperature range is about -40°C to 85°C. Generally used in industrial environments, but also able to operate outdoors where the environment is not so good or where there is interference. Compared to commercial grade products, industrial grade products can withstand more extreme environments, and are suitable, expected, or required to be used in types or qualities for industrial use, such as transportation, factory automation, and high shock and vibration environments.

(3) Automotive grade

The temperature range is approximately -40℃ to 125℃. Generally used in automobiles or harsh environments, due to the high heat generated during the start-up process of automobiles, it will be a bit higher in terms of high temperature and more expensive than industrial grade, which may be subject to high levels of EMI, collision, shock and vibration, and extreme temperatures. This type of product is therefore designed for automotive, transportation and other mission-critical applications and meets industry-standard automotive specifications.

(4) Military Grade

The temperature range is approximately -55℃ to 150℃. Generally used in military equipment, so the requirements are also the most stringent, mainly used in missiles, aircraft, tanks, aircraft carriers and other military fields. Grade is the most advanced, high precision, advanced technology and at the same time expensive, military grade is generally several years ahead of industrial grade time.

Classification and application of pcb gold fingers

In modern high -tech equipment, many devices need to be connected to each other, which requires signal transmission. How to connect the two devices, the golden finger is an important hub in it. The golden finger is a connection contact between the motherboard and the graphics card or sound card.

The technology used to transmit these signals and commands is a huge leap for early electronic technology. Early electronic technology is usually composed of independent modules, which is difficult to communicate with each other. With the golden finger, the process of a circuit board was immediately read by the main processing board.

WHAT ARE GOLD FINGERS?

Gold fingers are the gold-plated columns that you see along the connecting edges of printed circuit boards (PCBs). The purpose of gold fingers is to connect a secondary PCB to the motherboard of a computer. PCB gold fingers are also used in various other devices that communicate via digital signals, such as consumer smartphones and smartwatches. Gold is used for the connecting points along a PCB because of the alloy’s superior conductivity.

There are two types of gold applicable to the PCB gold finger plating process:

       ➤Electroless Nickel Immersion Gold (ENIG): This gold is more cost-effective and easier to solder than electroplated gold, but its soft, thin (typically 2-5u” composition renders ENIG unsuitable for the abrasive effects of circuit board insertion and removal.

       ➤Electroplated Hard gold: This gold is solid (hard) and thick (typically 30u”), thus more ideal for the abrasive effects of constant PCB usage.

Gold fingers make it possible for different circuit boards to communicate with one another. From the power source to the device or equipment, signals must pass between several contacts for a given command to be enacted.

Once you press a command, the signal will pass between one or more circuit boards before it is read. For example, if you press a remote command on a mobile device, the signal will be sent from the PCB-enabled device in your hand to the near or distant machine, which in turn receives the signal with its own circuit board.

Golden finger classification

Generally speaking, the main role of gold finger is connection, so it must have good conductive performance, wear resistance, antioxidant performance, and corrosion resistance. According to its performance characteristics, the gold finger is divided into the following:

① Conventional gold finger: Qiping’s finger is characterized by the edge of the PCB board. The position is neatly arranged and the same length. The width of the pads is rectangular and widely used. It is often found in the type of network card and graphics card.

② long -term gold finger: that is, unsatisfactory gold fingers, characterized by rectangular pads with difficulty in the length of the PCB board, often found in memory, U disk, card reader, etc.

③ Segment gold fingers: In the new gold finger, unlike long and short gold fingers, segmented gold fingers are rectangular pads located at different lengths of the board, but the front end is broken.

What is the PCB gold finger plating process?

Here is a list of the process for hard gold plating to PCB gold fingers:

1) Covered with blue glue

In addition to the PCB gold finger pads that require hard gold plating, the rest of the PCB surface is covered with blue glue. And we make the conductive position and the direction of the board is consistent.

2) Remove the oxide layer on the copper surface of PCB pads

We use sulfuric acid to wash off the oxide layer on the surface of the PCB pads and then clean the copper surface with water. We then grind to further clean the PCB pad surface. Next, we use water and deionized water to clean the copper surface.

3) Electroplating nickel on the copper surface of PCB pads

We energize the cleaned gold finger pad surface to electroplate a nickel layer. Next, we use water and deionized water to clean the nickel plated pad surface.

4) Electroplating gold on nickel-plated PCB pads

We electrically plate a layer of gold on the surface of the nickel-plated PCB pads. We recover the remaining gold. Then we clean the gold finger surface with water and then deionized water.

5) Remove the blue glue

Now the hard gold plating of the PCB gold fingers is completed. We then remove the blue glue and continue with the PCB fabrication to the soldermask printing step.

How to use PCB Golden Finger

1. Edge Connectors
When an auxiliary PCB is connected to the main board, it does so through one of several female slots, such as PCI, ISA or AGP slots.
Through these slots, the gold fingers conduct signals between the peripherals or internal cards and the computer itself.

Edge connector sockets are surrounded by a plastic box that opens on one side and has pins at one or both ends of the longer edge. Typically, connectors contain tabs or notches for polarity to ensure that the correct type of device is inserted into the connector. The width of the socket is chosen based on the thickness of the connection plate. On the other side of the socket is usually an insulated piercing connector that connects to the ribbon cable. The motherboard or daughter card can also be connected to the other side.

2. Special adapters
Gold fingers Many performance enhancements can be added to a personal computer. By plugging vertically into the motherboard’s auxiliary PCB, the computer can provide enhanced graphics and high-fidelity sound. Because these cards are rarely connected and reconnected individually, the gold fingers are usually more durable than the cards themselves.

3. External Connections
Peripheral devices that have been added to the computer station are connected to the motherboard via PCB gold fingers. Devices such as speakers, subwoofers, scanners, printers, and monitors are plugged into specific slots on the back of the computer tower. In turn, these slots connect to the PCB that is attached to the motherboard.

Design Rules of PCB Gold Fingers

●Keep plated through holes away from the fingers by at least 1mm. Plated through holes require copper plating around the hole on all layers. This copper can flow onto the gold fingers during plating and cause contamination or plating thickness issues. Maintaining a 1mm keepout prevents this.

●Maintain spacing between the fingers and any solder mask or silkscreen printing. This prevents material from overflowing onto the fingers during application which can interfere with insertion.

●Orient the fingers on the side of the board opposite from the component center. This aids in insertion and alignment as it clears components on the bottom side.

●Do not place any SMD parts, plated through holes, or solder pads within 1mm of the fingers. This prevents interference with the interfacing connector.

●Remove all inner layer copper beneath the fingers, typically 3mm beyond the edge of the finger width. This prevents inner layer copper from being exposed during PCB beveling/chamfering which looks bad aesthetically.

●Limit the maximum finger length to around 40mm. Longer fingers are prone to damage during handling and insertion.

●Avoid soldermask or silkscreen printing in areas immediately adjacent to the fingers where material can overflow causing buildup issues.

●Design continuous openings in the solder mask around the fingers. This prevents the need for score lines or steel mesh.

PCB gold fingers play an important role in electronic products. They not only connect circuit boards and other electronic components, but also transmit signals and currents.The production process of PCB Gold Finger includes plating and anti-corrosion treatment to increase its electrical conductivity and corrosion resistance.PCB Gold Finger is widely used in cell phones, computers and automobiles. Through a deeper understanding of PCB gold fingers, we can better understand the principles of connection and transmission in electronic products.

OSP PCB surface processing process and advantages

OSP (Organic solderable preservatives) is a lead -free surface treatment process, which is mainly used for SMT surface -packed circuit boards. Compared to the traditional HASL (HOT Air Solder Leveling) process, the OSP process does not require high -temperature melting treatment, which can reduce the risk of metal corrosion, environmental pollution and electronic component damage, so it is widely used in the electronic manufacturing industry.

OSP principle

The basic principle of the OSP process is to coat a layer of organic substances on the PCB surface to form a protective layer to prevent copper surface oxidation and corrosion. This protective layer is generally mixed with chemicals such as organic acids and nitrogen. The main chemicals include:

1. Organic acid: such as acetic acid, propionic acid, etc., mainly used to regulate pH values and enhance chemical reactions.

2. Nitride compounds: such as nitric acid, nitrite, etc., which are mainly used to increase the adhesion and durability of the protective layer.

3. Other additives: such as surfactants, anti -oxidants, etc., to increase the stability and durability of the coating agent.

Step of OSP process

1. Pre -processing: Chemical treatment on the PCB surface, remove oxides and pollutants, so that the surface is clean and smooth, which is convenient for subsequent coating and response.

2. Coating: Apply a layer of OSP coating agent on the surface of the PCB, and form a protective layer through drying and other processes.

3. CIT of: Put PCB in a cured furnace, heated it to a certain temperature, so that the OSP coating agent is solidified to form a protective film.

4. Detection: The solidified PCB is detected, including testing of indicators such as adhesion, thickness, and flatness.

5. SMT Paste: Put the electronic component on the surface of the PCB processing after OSP processing.

 

The OSP process has the advantages of environmental protection, lead -free, and suitable for microelectronics manufacturing. However, its processing process is more complicated and requires strict control of the composition and quality of coating agents to ensure the quality and stability of PCB. When using the OSP process, you need to pay attention to the following issues:

1. The composition and quality of theOSP coating agent have an important impact on the quality and stability of PCB. It should be selected for the appropriate chemicals and suppliers to avoid using inferior coating agents.

2. The coating thickness of theOSP coating agent also has an important impact on the quality and stability of PCB. It should be selected different thickness according to different PCB requirements. Generally speaking, the thickness of OSP coating agent should be controlled at 0.2-0.5um. between.

3. The curing time and temperature of theOSP coating agent are also very important for the quality and stability of the PCB. You should choose the appropriate curing conditions according to different coating agents and PCB requirements.

4. The adhesion and durability of theOSP coating agent are also the key indicators of the quality of PCB. It should be ensured by strict quality testing and testing to ensure its quality and stability.

5.OSP process is a green and environmentally friendly lead -free surface treatment process. It uses organic polymers as coating agents to form a protective film on the PCB surface to protect the PCB surface without oxidation or corrosion. Compared with the traditional Hasl process, the advantage of the OSP process is that the coating agent is environmentally friendly, uniform coating, non -welded ball, and easy to weld. Therefore, in modern electronics manufacturing, the OSP process is widely used.

OSP advantage

The advantages of OSP can be summarized as:

• Simple process and reusable use: The circuit board with OSP can easily be re -made by PCB manufacturers. In this way, once the PCB preparation personnel find that the coating is damaged, the new coating can be used.

• Good wettability: When the welds encounter holes and pads, OSP coated circuit boards perform better in welded wetting.

• Environmental friendly: Because water -based compounds are applied in the generation of OSP, it will not cause harm to the environment, and it will only fall into people’s expectations for the green world. Therefore, OSP is the best choice for electronic products that meet green regulations such as ROHS Essence

• PCB cost benefits: As simple compounds and simple manufacturing processes are applied during the OSP manufacturing process, the cost of OSP in all types of surface processing is very prominent. Its cost is lower, resulting in the lower cost of the final circuit board.

• Return welding suitable for double -sided SMT assembly: With the continuous development and progress of OSP, it has been accepted by single -sided SMT assembly and double -sided SMT assembly, which greatly expanded its application field.

• Low welding ink requirements: The storage requirements of OSP PCB for long storage time requirements Due to the very thin preservatives produced by OSP technology, it is easy to cut, so it must be very careful during transportation and transportation. OSP is exposed to high temperature and high humidity for a long time as a surface -processed PCB, which may occur on the surface of the PCB, which often causes low -weldability.

How OSP Manufactured

1.The first step is cleaning, which removes organic contaminants such as oil and oxidation films from the copper foil, the main component of the OSP. Insufficient cleaning can result in an uneven thickness of the created preservative. To achieve high-quality OSP films, the concentration of the cleaning liquid must be within a certain range according to laboratory standards. The cleaning process must be regularly monitored to ensure the required standard is met. If the desired results are not achieved, the cleaning liquid should be changed.

2.The second block is Topography Enhancement, where micro-etching is used to remove the oxidation produced on the copper foil that causes strong bonding between the copper foil and organic solderability preservative solution. The film build rate depends on the micro-etching speed. To achieve a smooth film thickness, the speed of micro-etching must be stable. The range for micro-etching speed is about 1.0 to 1.5 micrometers per minute.

3.The best option is to use a rinse before creating the preservative, as OSP solution can get polluted by ions, which can cause tarnishing after the completion of the reflow soldering process. In addition to that, DI rinse must be used after the creation of the preservative with a pH value of 4 to 7. If these parameters are not followed, the preservative can be destroyed due to pollution.

4.The OSP PCB coating is then applied to the cleaned copper surface through an adsorption process. The OSP solution contains organic compounds such as benzimidazoles, imidazoles, and benzotriazoles that form a thin layer on the copper surface. The thickness of the coating can be controlled by adjusting the concentration and immersion time of the solution.

5.After the coating is applied, the PCB is dried and cured in a controlled environment to remove any remaining moisture and to ensure proper adhesion of the OSP layer.

6.Once the coating is applied, the PCB is inspected for any defects or irregularities. The OSP-coated circuit boards are then subjected to various PCB tests to ensure their quality, reliability, and performance.

Application of Multi-layer PCB in electronic manufacturing

Electronic equipment can be seen everywhere in our lives, and some electronic products have become our indispensable supplies. We depend on them, while electronic equipment depends on the printing circuit board. PCB is the core component of most products now, and the basic functions are determined through the combination of components and wiring mechanisms.

PCB is divided according to the level, which can be divided into: single -layer circuit board, double -layer circuit board, and multi -layer circuit board. What we want to discuss today is the multi -layer circuit board. The simple -functional circuit board mainly uses a single-layer PCB, but more complicated electronic products, such as the computer motherboard, consist of multi-layer. With the increasingly complex of modern electronic products, these multi -layer PCB are more popular than ever, and manufacturing technology has greatly reduced their size.

What is multi-layer PCB

Multi-layer PCB is a printing circuit board composed of a multi-layer conductive layer and insulating layer. This circuit board is mainly used in high-end electronic products, such as wireless communication, computer, industrial automation, medical equipment and other fields.

Multi -layer PCB is composed of multiple conductive layers, which are separated from each other through the insulation layer. On each conductive layer, there is a layer of thin copper foil, which forms circuit graphics by chemical etching or mechanical drilling. The adjacent conductive layers are connected through the hole.

Compared with single -panels or double panels, multi-layer PCB has higher circuit density, better electromagnetic compatibility, lower circuit noise and better heat dissipation performance. Its production process is relatively complicated, and multiple steps such as copper foil coverage, chemical etching, drilling, printing, copper plating and other steps are required. These steps require high technical level and strict process control to ensure the quality and stability of the final product.

The design and manufacturing of multi-layer PCB requires many factors, such as appearance, size, number of layers, how to place components, how to arrange wires, drilling, pads, etc. The key is to optimize the internal wiring to improve the performance and reliability of the circuit.

Multilayer PCB Benefits

From a technical point of view, multilayer PCBs present several advantages in design. These benefits multilayer PCBs present include:

• Small Size: One of the most prominent and lauded benefits of using multilayer PCBs lies in their size. Because of their layered design, multilayer PCBs are inherently smaller than other PCBs with similar functionality. This presents a major benefit to modern electronics, as the current trend is working toward smaller, more compact yet more powerful gadgets like smartphones, laptops, tablets and wearables.

• Lightweight Construction: With smaller PCBs comes less weight, especially as the multiple connectors required to interlink separate single and double-layered PCBs are eliminated in favor of a multilayered design. This, again, is beneficial for modern electronics, which are geared more toward mobility.

• High-Quality: Due to the amount of work and planning that must go into the creation of multilayer PCBs, these types of PCBs tend to be better in quality than single and double-layer PCBs. They also tend to be more reliable as a result.

• Increased Durability: Multilayer PCBs tend to be durable by their nature. Not only do these multilayer PCBs have to withstand their own weight, but they must also be able to handle the heat and pressure used to bind them together. On top of these factors, multilayer PCBs use multiple layers of insulation between circuit layers, binding it all together with prepreg bonding agent and protective materials.

• Enhanced Flexibility: Though this does not apply to all multilayer PCB assemblies, some do use flexible construction techniques, resulting in a flexible multilayer PCB. This can be a highly desirable trait for applications where mild bending and flexing may occur on a semi-regular basis. Again, this does not apply to all multilayer PCBs, and the more layers incorporated into a flexible PCB, the less flexible the PCB becomes.

• More Powerful: Multilayer PCBs are extremely high-density assemblies, incorporating multiple layers into a single PCB. These close-quarters enable boards to be more connective, and their innate electrical properties allow them to achieve greater capacity and speed despite their smaller size.

• Single Connection Point: Multilayer PCBs are designed to work as a singular unit, rather than in tandem with other PCB components. As a result, they have a single connection point, rather than the multiple connection points required to use multiple single layer PCBs. This proves to be a benefit in electronic product design as well since they only need to include a single connection point in the final product. This is particularly beneficial for small electronics and gadgets designed to minimize size and weight.

These benefits make multilayer PCBs highly useful in a variety of applications, particularly mobile devices and high-functioning electronics. In turn, with so many industries turning to mobile solutions, multilayer PCBs are finding a place in an increasing number of industry-specific applications.

Advantages of Multilayer PCBs over Single Layer Alternatives

When compared to single layer alternatives, the advantages of multilayer PCBs become even more pronounced. Some of the key improvements multilayer PCBs offer include the following:

• Higher Assembly Density: While single layer PCBs’ density is limited by their surface area, multilayer PCBs multiply their density through layering. This increased density allows greater functionality, improving capacity and speed despite the smaller PCB size.

• Smaller Size: Overall, multilayer PCBs are smaller in size than single layer PCBs. While single layer PCBs must increase the surface area of the circuit by increasing size, multilayer PCBs increase surface area through the addition of layers, decreasing overall size. This allows for higher-capacity multilayer PCBs to be used in smaller devices, while high-capacity single layer PCBs must be installed into larger products.

• Lighter Weight: The integration of components in a multilayer PCB means less of a need for connectors and other components, resulting in a lightweight solution for complex electrical applications. Multilayer PCBs can accomplish the same amount of work as multiple single-layer PCBs, but does so at a smaller size and with fewer connecting components, reducing weight. This is an essential consideration for smaller electronics where weight is a concern.

• Enhanced Design Functionality: Overall, multilayer PCBs are capable of being more than the average single layer PCB. With more incorporation of controlled impedance features, greater EMI shielding and overall improved design quality, multilayer PCBs can accomplish more despite their smaller size and lesser weight.

Application of Multilayer PCB

Multi-layer PCB is widely used in various high-end electronic products, including but not limited to the following fields:

1. Communication equipment: Multi-layer PCB plays a key role in communication devices such as mobile phones, routers, satellite communication, etc., and realizes high-speed data transmission, signal processing and power management functions.

2. Computer hardware: Multi-layer PCB is widely used in hardware such as computer motherboards, graphics cards, and memory strips. It provides high -density and high reliability circuit wiring to ensure the stable operation of the computer system.

3. Industrial automation: Multi-layer PCB is widely used in industrial automation equipment, such as programmable controllers, sensors, motors controllers, etc. Its high reliability and durability meet the needs of industrial automation equipment.

4. Medical equipment: Multi-layer PCB is also widely used in medical equipment, such as monitor, ECG, ultrasound equipment, etc., its miniaturization, high density and reliability provide strong support for the performance of medical equipment.

5. Aerospace: The application of multi-layer PCB in the field of aerospace is very important because this field requires high reliability and durability electronic equipment. The characteristics of high-density wiring, electromagnetic compatibility and heat dissipation performance of multi -layer PCB meet the needs of the aerospace field.

6. Car Electronics: Multi-layer PCB is also widely used in automotive electronics, such as engine control modules, airbag control modules, etc. Its high reliability and durability can ensure stable operation in the harsh working environment of the car.

Get a Manufacturer For Your Multilayer PCB

Lst is a Custom PCB SORUTIONS Provider, Serving Companies the World in PCB ManuFacturing and Assembly Services. We Help Companies Sourcing To Testing, ALL The Who Remaining Compliant with IPC Class 3, Rohs and ISO9001: 2008 Standards.

We can design a variety of complex multi -layer circuit boards for you. We have an experienced production technology team to track the processing of multi -layer circuit boards throughout the process. Any of your needs, LST can be met.

15 common PCB faults and solutions

Regardless of whether it is an engineer or a PCB manufacturer, it is impossible to avoid PCB failures. The emergence of these faults may lead to delayed product intersection and affected the reputation of the manufacturer, increasing time and money costs.
Today is mainly about the PCB fault mode and the PCB failure solution. Here we mainly list the following 15 PCB fault modes, let’s analyze this.

1. PCB crack or bend

Reason: Due to high mechanical or physical stress, printing circuit board components (PCBA) may be ruptured or bent. For example, if the rigid PCBA is placed under repeated vibration or thermal shock, it may fail. In addition, if your curved strength exceeds its ability, even flexible PCBA will break.

PCB crack

Prevention method: Before using PCB during the assembly process, bake PCB and store it in a cabinet with humidity control to remove any water in the naked PCB to avoid impact caused by the later stages of assembly.

2. The assembled PCB components have obvious polarity

Reason: When designing the PCB layout, if the component on the printed circuit board component is not obvious, it may lead to the problem of polar counter -connection. For example, if the battery pole is reversed, the battery and electrical components may be damaged. Printing circuit board components may also fail, and electric shocks may occur.

PCB components have obvious polarity

Prevention method: You can use diode or Schottky diode to reduce the effects of reverse polarity. If you connect the diode with the battery, the circuit will be turned off in the opposite situation, it will prevent any major damage to the printed circuit board component.

3. PCB solder joint break

Reason: The difference between the thermal coefficient and electronic component of the PCB may cause the solder joints to break. If the printed circuit board components are placed in a repeated high or low temperature environment, a failure may occur. Another reason may be manual welding, which makes welded more vulnerable to thermal stress.

PCB solder joint break

Prevention method: It would be much better if you use a special automatic machine to welded electronic components. Before sending the PCB to the assembly process, make sure you have visited inspection.

4. PCB corrosion

Reason: Since there may be some residues during the PCB assembly, there may be some residues, so the printed circuit board component may be corroded. The welding agent is essential to ensure the safe connection of electrical components. However, once contact, it will also cause their corrosion.

Prevention method: Welds are composed of organic acids, such as citric acid or adenic acid. PCB assemblers should ensure that any extra welded agents are eliminated from the PCB surface. This will not help the solder to destroy the metal contact. If the PCB assembler uses a refund welding machine, you should remember to rinse any excess welding agent.

5. Burning or burning electronic components (short circuit)

Reason: During the PCB assembly, short circuit may damage PCB and electronic components. This may be short circuit due to the unexplained welding bridge, humid or accidental events (such as high -current peaks). Short -circuit will cause sudden and sudden damage to components, and may also cause damage to fire and electrical equipment.

Prevention method: Check the short -circuit situation of the PCB surface. For the inner layer, electrical testing is most suitable for the assembly of printing circuit boards. The test mainly checks whether there is short -circuit or opening. In addition, you can compare the obtained readings with the readings obtained from the probe test.
In addition, when designing the PCB layout, PCB assembly personnel must accurately align each layer. In this way, they will be able to work together and avoid any short circuits. You can also reduce the thickness of the PCB template to reduce the deposits of welded paste.

6. Copper weight is not suitable

Reason: For the good current in the printing circuit board component, the weight of the correct copper foil is necessary. If the copper weight is too thin or too thick, it will cause your print circuit board component to fail, which is mainly because the size determination and the width selection of the wiring width when designing the PCB layout.

 

Prevention method: PCB assemblers must follow the copper weight specifications required by PCB engineers. Copper cannot be too thick because it increases costs and cannot be too thin, because they may cause PCB to heat up.

7, component position movement

Reason: In PCB assembly, pick up and place or place components of the circuit board in other automatic machines. If the component is shifted or moved due to the welded weld during welding, the PCB may be faulty. It is mainly because reliable solder joints will not be formed and may cause the road.

Prevention method: PCB assemblers should follow the standard humidity and temperature requirements. They may use more accurate pickup and placing machines to accurately place components. In addition, if you still use more corrosive welding agents, it will improve the weldability of parts, which can keep the electronic components in the original position.

8. The warranty period of electronic components expires

Reason: If any single component in the printed circuit board component fails, it may cause the entire PCB component to collapse, and parts may fail due to reverse selection. If these components are not limited, they will be helpful. In addition, if you choose a low -quality component, it will reduce the service life of the parts, and it may not even be before the warranty period expires.

Prevention method: You should carefully select the component or ask your PCB factory to do so. The parts should not be damaged or the quality should be low (electronic component preparation). In addition, you can directly add components to prepare damage.

9. PCB hot pressure or wet pressure

Reason: Different materials have different expansion rates. Therefore, when a constant a thermal stress is applied, it will damage the solder joint and damage the component. If the wrong copper weight or electroplating problem is used, the stress of thermal factors will increase. Even in the process of manufacturing, the temperature of the assembly PCB room will affect its performance.

Prevention method: PCB assembly personnel must conduct a careful circuit board inspection, prepare, and then clean the necessary cleaning. Pencil rubber rubbing can eliminate any slight corrosion or rust. You can identify the sub -light copper pad through their dark brown. Welds are not sticky to the surface of rust, and must be applied after cleaning, and excess is removed with the welding core.

10. Problems of PCB welding process

Welded welds are very important for the work of electronic circuits, so pay more attention. The most common problems related to soldering are the conditioning conditions for welded pollution and bad processing. The welding agent is a chemical cleaner used before and during the circuit board. Some welded residues will absorb the possible conductive moisture, which will cause short circuit. If the welding process is not set and controlled correctly, the connector can be opened and pollution.

11. PCB uses physical problems of materials

The materials used in PCB often encounters problems that cause the circuit board to fail. In the manufacturing stage, if a layer of PCB is not aligned, it will cause short -circuit, opening and cross -signal lines. If the material has a psychological defect such as breaks, empty holes, and layered, the performance of PCB will be seriously affected. If the material used is not pure, it will also fail.

12. Chemical fluid leaks in electronic components in PCB

The existence of any chemical liquid leaked in the component will severely damage the PCB and cause failure. Most chemicals are removed during the manufacturing process. However, trace elements may be left. Inside the packaging of the component, leaks may occur, which will cause semiconductors or packaging rapidly. This chemical leak will eventually lead to short -circuit or corrosion.

13. PCB component design failed

One of the most common reasons for PCB failures is incorrect components due to insufficient PCB space, power failure or overheating. Space is crucial, especially when the circuit board becomes more complicated and needs to meet harsh requirements. Here are only some examples of errors in the design and manufacturing stage. Don’t forget, you can avoid many such problems by following the correct PCB design rules.
Welding problem
Chemical (fluid) leakage
Component barrier damage
Wrong component placement
Burning component

14, inferior electronic components

It is not so easy to find an electronic component that conforms to the circuit design. Whether it is to ensure packaging or management components, it is very important to find high -quality electronic components when considering PCB assembly and manufacturing.
The tightly placed wiring and channels, poor welding of cold welds, poor connection between circuit boards, insufficient circuit board thickness, and use of counterfeit elements are just some problems that may face.

15. PCB placement environment

PCB is exposed to heat, dust and humidity, accidental impact (falling and falling), and power supply/waves, which may be the cause of circuit board failure. However, the most destructive reason for the premature failure of the circuit board is the electrostatic discharge (ESD) in the assembly stage. Electricity discharge (ESD) is a sudden current flow caused by short circuit or dielectric breakdown between the two electric objects. Static accumulation may be caused by friction charging or electrostatic sensing.

The specifications and requirements of PCB Silkscreen designed.

PCB Silkscreen design mainly refers to the design of the silk layer printing on the printing circuit board (PCB). The silk layer is a special layer on the PCB, which is used to print various texts, symbols and graphics, such as circuit points, components, circuit symbols, etc. This information is mainly used for various components and functional areas on the identification, identification and management of PCB.

In the PCB Silkscreen design, many factors need to be considered, such as space restrictions, information importance and readability. Due to the limited PCB surface space, designers need to decide which information is the most critical and prefer to display this information in the silk print layer. For example, component reference signs, polar marks, pins 1 labeling, component boundary, company logo, manufacturing trademark, warning symbols, component numbers, version numbers, and date code are all common silk print content.

Design PCB Silkscreen usually uses EDA (electronic design automation) software. Designers can identify and assemble all the necessary marks, symbols and texts required for components on PCB, and then export the format that can be used by manufacturers. Modern PCB Silkscreen design usually uses a digital inkjet printer to print the screen printing image to the surface of the PCB, while the initial screen printing technology uses the screen printing method.

Importance of PCB Silkscreen

In order to lay the right background on a silkscreen PCB role, it is important that we recall the uses of a printed circuit board (PCB). PCB offers mechanical support and helps in connecting electronic components. PCBs have signal traces, conductive pathways, or copper sheet-etched traces that are laminated to a substrate (non-conductive).

The conductive tracks and components of the PCB are seen throughout the board without the right identification. This is why it is necessary for end-users and manufacturers to exist. This helps them to identify components such as:

▶Manufacturer identifiers
▶Testing points
▶Warning signs like high voltage
▶Processing types
▶Version numbers like V2, V3, etc.
▶Component orientation and numbers
▶Company logos i.e. manufacturer name

The importance and roles of silkscreen PCB include:

▶Identifying circuit points such as part interconnect, testing points, etc. quickly
▶Useful in troubleshooting circuits in case you get a defective component or a contrasting outcome
▶It helps you quickly identify components whenever you are designing or replacing evaluation requirements.
▶It serves as a form of safety by showing some warning signs, such as grounding, high voltage, etc.
▶Silkscreen PCB also helps manufacturers dung marketing and branding purposes. However, it prevents illegal duplication or forgery of circuit designs.

Silkscreen PCB is also great for evaluating products, such as rating verifications. Note that the information of your silkscreen depends on the size of your board. If your silkscreen board is a small one, make sure you take the important information seriously.

Silk print design requirements

The ratio of the word height to the word width of the silk print character is generally required ≥6: 1. There are three common font samples: where the board density is relatively large, the character of 4/25mil is commonly used (No. 1); when the conventional density is recommended, it is recommended to 5/recommended 5/ 30mil characters (No. 2); when the board is relatively loose, it is recommended to 6/45mil characters (No. 3); usually the thickness of the surface of the surface of the surface also has corresponding requirements for the width of the silk print: When the thickness of the base is 1oz, the 5/30mil character is preferred; when the base copies are 2oz, the 6/45mil character is preferred.

PCB Silkscreen requirements

1. Placement position: Generally speaking, the wire printing of resistors, capacitors, pipes and other devices should not be used in four directions when placing. This will cause debugging, maintenance, and welding.

2. Try not to hit the silk print as much as possible.

3. Do not press on the high -speed signal line (such as, clock line, etc.): For high -speed signal lines on the top or bottom layer, because this type of signal line can be regarded as a microstrip line.

4. The reading direction of the silk print should be consistent with the reading direction of the silk printing and the use direction of the chip. It is mainly because the probability of welding is reduced when welding.

5. The pins are clearly marked on the silk print.

6. Special packaging Silk Printing: For special packaging such as BGA and QFN, the size of the silk print must be exactly the same as the size of the chip.

7. Silk printing of the installation hole: The screws are added near the installation hole, and the total length and screws are marked for easy installation.

8. The two meaning of silk printing: the most commonly used RS232, many people will mark RX and TX, but there are RX and TX on the PC side. When do you use cross lines and when do you use it? Misty is unclear.

PCB Silkscreen design precautions

1. The width of the wire printing line on the board is ≥4mil, and the width of the component wire printing line is 0.

2. Silk printing and pad distance: Do not cover the welding point on the board, such as patch device pads, plug -in holes, silk printing as insulating material, once pads are put on , Mark point, etc.; usually require a 6mil spacing.  

3. Sitries between silk prints: It is acceptable to keep 6mil. There is a coincidence between the silk seal. Once the coincidence is overwhelmed, it needs to be adjusted.  

4. Silk printing direction: Silk print string arrangement should follow: the principles of string from left to right or from bottom to top when facing the right look.

5. The device bit number is placed: the device bit number should correspond to the device one by one, and cannot be reversed and transforms the order; when the density density is relatively high, you can use the method of drawing or symbolic labeling to place the bit number on the board other other boards. There is space.

6. The polar identity of the component and the “1” foot logo should be placed correctly and clearly.

7. When the labeling or symbol labeling, the added silk prints and characters added should be placed on the silk layer of Board Geometry.

The added board name number silk print is also placed on the silk seal layer of Board Geometry.  

8. The device bit number cannot be placed in the device or outside the board.  

9. When the density of the board is relatively high, when there is no space for placing the bit number, you can discuss with the customer not to sign, but you need to install pictures to facilitate the installation and inspection of the guidance device.

10. When the customer is required to write copper characters on the bottom layer, the line bronze line width: HOZ base bronze: character width above 8mil, height of 45mil or more; 1oz base bronze: more than 10mil in the character; above 50mil. At the same time, you need to do a good job of welding windows, so that the copper characters produced on the board are relatively bright.

Three Main Process Methods Of Silk Screen Printing.

The following are the most common PCB silk screen technology processes and processes on PCB:

▶Manual Silk Screen PCB: This process can be used when the line width is greater than 7mm and the registration tolerance is 5mm. For this method, you will need pcb silkscreen minimum text size and trace template made of nylon. The oil is printed onto the plate through the stencil. Next step,make the PCB board baked in a curing oven and let it to besolidification.

▶Liquid Photo Imaging (LPI): This procedure supplied greater correctness and legibility than manual screen printing. Using this method when the trace width is greater than 4 mil. Liquid photo imaging is very similar to the process of applying solder mask. In this case, a liquid photoimageable epoxy was applied to the laminate and then exposed to UV light. After that, the PCB board is developed and cured.

▶Direct Legend Printing (DLP): This is the most correct way to add PCB silk screen, but it is very high-priced. In such pcb silkscreen process, using an inkjet projector with acrylic pcb silkscreen ink, which have relevance to the original print circuit board from the CAD data. The pcb silkscreen acrylic inks is solid with UV light during printing. It should be noted that acrylic inks will not cure on boards with a silver finish.

Understand PCB Screen Printing Cost.

Due to the fixed cost characteristics, the cost of PCB screen printing is placed in the first place of non recurring tools in the PCB design process. PCB screen printing process accounts for about 15% of the total cost from PCB manufacturing cost.

1.The minimum text size design of PCB screen printing refers to the change of character width, height, PCB screen printing thickness, spacing and character position. Art fees are usually not charged separately.

2.The cost of PCB screen printing ink depends on the screen printing method used. Acrylic ink is used for the DLP method of legend printing, while other methods use epoxy ink.

3.The cost of PCB screen printing ink decided by specific features, such as curing procedure, adhesion,substrate compatibility, and immunity to acid / alkali treatment.

4.PCB screen printing color is also a decisive cost factor. The cost of white ink silkscreen is lower than that of other color inks. By optimizing the cost of PCB screen printing through the selection of PCB screen printing materials, the total cost of PCB can be reduced by about 5%.

5.The screen printing method that used also has an effect on the total cost. The cost of LPI for liquid photo imaging and DLP for direct legend printing is higher than that of manual screen printing because of the high capital cost of setup.

6.Another important factor to consider in the cost calculation of screen printing is whether you want to print legends on both sides or just on one side. In the case of both parties, the cost will rise.

Conclusion

The process of PCB silkscreen is delicate. This is because the quality of the printed circuit board can be affected. Another aspect you must consider closely is the cost aspect during the design. Furthermore, having a good understanding about the whole process of screen printing as well as the benefits and pitfalls of each of the printing methods ensures that it becomes easy to decide if you should do a DIY PCB silkscreen or consult the services of any professional manufacturer.

Quick Turn PCB Manufacturing Guide: How to choose manufacturer

Quick Turn PCB manufacturing means that PCB can complete mass production in a short time, so it is named “Quick Turn PCB”. Fast PCB can help customers realize the rapid entering the market, while ensuring sufficient capacity. High -quality, high efficiency, and relatively low cost make the Quick Turn PCB manufacturing very popular.

The advantage of fast PCB manufacturing

The advantages of fast PCB manufacturing mainly include the following points:

1. Quick delivery: The traditional PCB manufacturing process may take several days or weeks to complete, and the Quick Turn PCB manufacturing can be completed in just a few hours, which greatly shortens the product listing time.

2. High -precision: Quick TURN PCB manufacture uses high -precision laser or lithography technology, which can make PCB with high precision lines and details, which improves the reliability of the circuit.

3. Low cost: Although the initial investment manufactured by Quick Turn PCB may be high, due to its fast and high -precision characteristics, it can save a lot of time and cost in the long run.

4. Flexibility: Quick Turn PCB manufacturing allows designers and engineers to ite and modify during the manufacturing process to better meet product needs.

5. Customization: Quick Turn PCB manufacturing can customize the size, shape and materials of PCB according to the needs of the customer, thereby meeting various application needs.

Quick Turn PCB Prototypes

A PCB prototype is a fabricated PCB that is created to check and evaluate the functionality and capability of the final PCB assembly that is the objective of production, to make sure it meets the current required technical and electrical applications.

These prototype PCBs are created with all the functionalities and properties that are expected from the final finished PCBs. Prototypes help prove the PCB design, providing the avenue to thoroughly test it and resolve any performance or regulatory compliance issues before full manufacture commences.

The prototype stage is where the correction, addition, or omission of features are done to ensure that the final PCB assembly is without any technical errors. This is done before the quick turn automation begins in earnest. Therefore, valuable time is invested in prototype testing to support efficiency and performance.

Early prototypes can be drastically different from the finished product. Therefore, the first batch of prototypes is usually done in smaller quantities. Prototypes are crucial because it is difficult to make changes to a finished PCB.

Quick turn PCB prototypes are therefore beneficial for the following reasons:

●Save significant manufacturing costs.

●Avoid manufacturing defects or spotting them at an early stage for correction.

●Save valuable delivery time by meticulously checking the design for manufacturability.

●Avoid manufacturing delays by reducing changes during production.

●Provide chances for manufacturers to make adjustments before full production, based on client and user feedback.

How to ensure the quality of Quick Turn PCB manufacturing

To ensure the quality of the Quick Turn PCB manufacturing, the following measures can be taken:

1. Choose high -quality manufacturers: Choose a fast PCB manufacturer with good reputation and rich experience to ensure that its production technology and equipment meet industry standards.

2. Provide clear design files: ensure clear and accurate design files provided to the manufacturer, including the correct component layout, size, spacing and other details to avoid errors in the manufacturing process.

3. Make quality inspection: In the process of PCB manufacturing, quality inspection is very important. This includes random inspections of various stages of the manufacturing process to ensure that the PCB produced meets design requirements and quality control standards.

4. Perform factory testing: After the PCB manufacturing is completed, it is necessary to conduct a comprehensive factory test. This includes electrical performance testing, appearance inspection and dimensional measurement to ensure the quality and reliability of PCB.

5. Use automation equipment: The use of automated equipment for PCB manufacturing and testing can reduce human errors and improve production efficiency, thereby ensuring product quality.

6. Strengthen communication and collaboration: Maintain close communication and collaboration with the manufacturer, timely solve the problems in the manufacturing process, and ensure that the quality of the product has been improved and improved in a timely manner.

7. Standards and specifications: Follow the relevant PCB manufacturing standards and specifications, such as IPC standards to ensure that the PCB created has good reliability and consistency.

What Are The Factors That Affect The Delivery Time Of Quick Turn PCB?

1. The complexity of PCB design. Many PCB manufacturers claim to provide the same day PCB, next day PCB, or 24 hours PCB manufacturing services. But please don’t be deceived by the simple statements. The simple design of single-sided PCB or double-sided PCB can be delivered within 24 hours, while the turnaround time for more complex designs of flexible PCB and rigid-flex PCB takes 7-10 days.

2. PCB materials. Different PCB types require different production materials, and not all PCB manufacturers have stocks of unique material. When ordering PCBs, it is necessary to consider the purchase time of PCB raw materials.

3. Difficulty factor of PCB process. We know that there are various holes on the PCB, such as plated through holes, blind holes, buried holes, etc. Each blind hole and buried hole needs to use a drill or laser drilling, and drilling, lamination, electroplating, etc. require additional time. HDI PCB takes more time.

4. The manufacturing capabilities of PCB manufacturers. You need to check your PCB manufacturers’ infrastructure to determine if they meet your fast turnaround time needs.

Some factors you need to consider are:

♦The size of the PCB manufacturing company;
♦Whether they have invested in advanced production equipment;
♦Whether they can control and influence material suppliers;
♦Whether they can purchase high-quality PCB raw materials;
♦Whether the PCB manufacturing company manufactures in-house or partially outsources;
♦Do they have professional PCB engineers;
♦Their logistics capabilities: logistics methods, relationships with logistics partners, etc.;

5. Pricing

Please believe in the eternal truth: the cheapest is not necessarily the best. All PCB manufacturers have their characteristics and strengths in terms of quality, turnaround time, and price. We need to evaluate based on the comprehensive capabilities of the PCB manufacturer and the complexity of the PCB itself.

How to choose a Quick Turn PCB manufacturer?

When choosing a Quick Turn PCB manufacturer, you need to consider the following aspects:

➤Quality assurance: First of all, the quality assurance system of the manufacturer needs to be examined, whether it has passed the quality certification such as ISO 9001, and whether there is a strict quality control process.

➤Experience and professionalism: Choose manufacturers with rich experience and professional knowledge to better understand your needs and provide high -quality services.

➤Equipment and technology: Examine the equipment and technical level of manufacturers, including manufacturing equipment, technical technology, testing equipment, etc. to ensure its ability to make fast and high -precision manufacturing.

➤Delivery time: Understanding the delivery time of the manufacturer can meet your emergency needs.

➤Price: Compared the price of different manufacturers, and at the same time, considering factors such as quality, delivery time, and the highest price -effective supplier.

➤Services and after -sales: Choose a manufacturer with good pre -sales and after -sales service, which can solve the problems of manufacturing and after -sales problems in a timely manner.

➤Cases and reference: View the cases and customer feedback of the manufacturer to understand their actual performance and reputation.

When choosing a fast PCB manufacturer, it is recommended to conduct field inspections to understand its actual production situation in order to make more accurate judgments. At the same time, you can refer to the recommendations and evaluations of the same industry in order to better choose a reliable manufacturer.

Choose LST technology as your PCB manufacturer

We are Chinese professional fast PCB manufacturers. We have the industry’s leading on time and effectively solve many urgent problems for customers.
With our manufacturing facilities, we can provide all types of industries with fast circuit board manufacturing services and fast PCB prototype solutions, including medical, transportation, industrial applications, consumer goods, aerospace and military.
Each online PCB order includes a comprehensive engineering review before the start of circuit board manufacturing, eliminating delay and quality problems.

How to choose the correct PCB manufacturer in China?

If you are looking for a PCB manufacturer, China is undoubtedly a very good choice. China is currently the world’s largest PCB production base. It has advanced production technology and low production costs, so many companies choose to assemble PCB in China. Of course, China also has some small processing plants. Their strength is not so strong, and lacks certain competitiveness in high -end fields. Enterprises must also take comprehensive considerations when selecting PCB suppliers to ensure the smooth production plan.

We will focus on this article: how to choose the correct PCB manufacturer in China, we will discuss quality control measures, industry experience and customer support, and provide research and potentially communicating with potential manufacturers. At the end of this article, you will better understand what you should find among reliable PCB manufacturing partners, and how to find partners who meet your specific requirements.

Why choose China for your next PCB manufacturing project?

1.The country is emerging as a leading PCB manufacturing hub with an increasing global share of PCB output.

2.Almost all kinds of PCBs and various scales of manufacturing projects are efficiently dealt with in the country. Therefore, no matter what type of PCB manufacturing requirement you have, China has a company that offers you exactly the same.

3.Chinese manufacturers possess unmatched technical expertise, advanced technology and precise equipment to eliminate chances of errors and defects in the final product.

4.Like most electric and electronic components, custom-designed PCBs are also available at affordable prices in China.

5.In China, PCB manufacturers usually depict a top-notch level of professionalism. They offer exceptional client handling and service support. This helps customers stay updated throughout the manufacturing process. Chinese manufacturers prioritise communication which further helps build trust and a strong partnership between the customer and the manufacturing company.

What should you do before looking for PCB manufacturers?

Before looking for PCB manufacturers, you should be clear about your needs, including the specifications, types and functions of the PCB board, while understanding the product’s budget, mass production requirements, and the required delivery time. In this way, you can choose the right manufacturer to cooperate.

Specifically, you need to examine the professional level of the manufacturer, including the level of process, the degree of advancement of equipment and technology, and the operating efficiency of the production line. At the same time, paying attention to product quality, good manufacturers can not only meet the quality requirements, but also provide a longer warranty period. Considering the production capacity of the manufacturer, whether it can meet your production needs and ensure the timely delivery of orders. In addition, the price is also an important factor in choosing a manufacturer. It needs to evaluate whether the cost it costs costs cost -effective and whether it is in line with market price.

The factors that you need to consider when choosing a PCB manufacturing company

When choosing a PCB manufacturing company, you need to consider the following factors:

1. Production capacity: Ensure that the manufacturer has sufficient production capacity, can deliver orders on time and meet production needs.

2. Technical strength: Examine the technical strength of the manufacturer, including the technology, experience and equipment it own to ensure that it can provide high -quality products and solutions.

3. Quality control: Understand the manufacturer’s quality management system and quality control process to ensure that it can provide stable and reliable product quality.

4. Dating period: Dating is an important factor in measurement of the production capacity and efficiency of PCB manufacturing companies. It is necessary to ensure that the manufacturer can deliver orders on time and meet production needs.

5. Service level: Examine the level of pre -sales, mid -sales, and after -sales service levels, including technical support, maintenance, repairs, etc. to ensure that it can solve customer problems in time and provide technical support.

6. Cost benefits: Evaluate the price and delivery cycle of the manufacturer, whether it meets the budget and mass production requirements, and whether it can reduce the cost on the premise of ensuring the quality of the product.

7. Reputation: Understand the reputation and reputation of the manufacturer, including the rate of return of history and business, customer feedback information and evaluation rankings, etc., to ensure that it can ensure product quality and service level.

The way to find Chinese PCB manufacturers

Now you may want to know where and how to find the best company. To this end, you need to conduct thorough research and list the finalists according to the above list. To find your option:

1. Take a look at the Internet

2. Browse list platform/directory

3. Visit exhibitions, conferences and trade exhibitions

4. Recommended and recommended by colleagues or contacts in the industry

Communication with PCB Manufacturing Companies

Effective communication is key to establishing a successful partnership with a PCB manufacturing company in China. Here are two key aspects to consider when communicating with potential manufacturers:

▶Initial Contact
When reaching out to potential manufacturers, it’s important to prepare questions and information that will help you evaluate their capabilities and suitability for your project.

Ask about their quality control measures, industry experience, and customer support. Provide detailed information about your project requirements and ask if they have experience with similar projects.

Pay attention to how responsive the manufacturer is during initial contact. A prompt and thorough response is an indication of good customer service and a commitment to meeting your needs.

▶Follow-Up Communication
Once you’ve established contact with potential manufacturers, it’s important to maintain regular communication throughout the project.

Ask about their process for providing updates on progress and ensure that they assign a dedicated account manager to your project. Be prepared to provide feedback and ask questions as needed to ensure that the project stays on track.

Evaluate the manufacturer’s responsiveness and communication skills throughout the project. If issues arise, work with the manufacturer to find solutions and ensure that they remain committed to meeting your needs.

By maintaining open and effective communication with potential manufacturers, you can establish a strong partnership based on trust and shared goals.

China is the largest PCB manufacturing market. If you have PCB projects, you can definitely find a cost -effective production company in China. You can also contact us LSTPCB Manufacturing Company, we will quote you within 24 hours.

How to control the quality of pcb

Printed circuit boards are an integral part of electronic devices and are the core component that controls the entire device. pcb is used in a variety of applications including consumer electronics, automotive, aerospace, communications, medical devices and other industries.

Quality is the lifeblood of a product. pcb quality control processes, including visual inspection, functional testing and environmental testing. These processes are critical to detecting defects and ensuring that PCB assemblies function correctly and reliably.

In this article we will focus on the pcb component process, such as any control pcba quality, and emphasize the importance of quality control for the product. The details are as follows:

Basic Principles of Quality Control

IPC Standards
The IPC (Institute of Printed Circuits) sets industry standards for PCB design, assembly, and testing. IPC standards help businesses to maintain consistency and reliability in the final product.

Production Process Control
Production process control involves monitoring and controlling the entire production process to prevent defects and ensure consistency in the final product. This includes maintaining the temperature, humidity, and other environmental factors that may affect the quality of the final product.

Testing and Inspection
Testing and inspection are critical aspects of PCB assembly quality control. They involve using various methods such as automated optical inspection (AOI), X-ray inspection, and functional testing to detect and correct any issues that may arise during the assembly process.

PCB assembly quality control is a vital process that ensures that the final product meets the required performance standards and reliability. By implementing basic principles of quality control such as IPC standards, production process control, testing, and inspection, businesses can prevent defects and ensure consistency in the final product.

The importance of PCB quality control

The importance of PCB quality control is mainly reflected in the following aspects:

1. Ensure product performance: PCB is the core component of electronic equipment, its quality directly affects the performance of the entire product. Through strict quality control, you can ensure the quality of PCB manufacturing process, materials, layers, layout and wiring and other aspects of the quality, so as to ensure stable and reliable product performance.

2. Improve production efficiency: In the PCB production process, if there is a quality problem, it may lead to low production efficiency, or even need to rework or rework. Through quality control, we can find and solve the problem in time, avoid waste and delay in the production process, and improve production efficiency.

3. Reduce costs: PCB quality problems may lead to product damage, return or repair, etc., which will increase the cost of the enterprise. Through quality control, we can reduce the occurrence of these problems, thus reducing the cost of the enterprise.

4. Enhance corporate image: a strict quality control system can enhance the image and reputation of the enterprise, so that customers more trust and recognition of the enterprise’s products and services.

How to control the quality of pcb

First, the design stage: optimize PCB layout and circuitry

In order to improve the performance and quality of the PCB board, the design phase is crucial. Designers need to give full consideration to circuit layout, component selection and thermal management. In circuit design, factors such as electrical performance, signal integrity and electromagnetic compatibility should be given full attention. At the same time, the use of PCB design software, such as Altium Designer, Eagle, etc., can effectively reduce design errors, optimize the layout and improve design efficiency.

 

Second, the choice of materials: the selection of high-quality substrates and copper foils

The performance and quality of the PCB board depends largely on the materials used. In the manufacturing process, the selection of high-quality substrates and copper foil is critical. High-quality base materials can ensure the thermal performance and mechanical strength of the PCB, thus improving the reliability of the product. In addition, the selection of high-purity copper foil can improve conductivity, reduce resistance and improve circuit performance.

 

Third, the production process: strict control of process parameters

PCB production process process parameters to ensure the quality and performance of the PCB board is critical. These parameters include: copper sinking, etching, drilling, plating, screen printing, hot air leveling, etc.. Through strict control of these parameters, you can ensure that the size of the PCB board, line width, aperture, etc. to meet the design requirements, improve product reliability and performance.

 

Fourth, detection and testing: to ensure that products meet quality standards

For PCB board manufacturers, comprehensive inspection and testing of PCB boards produced is the key to ensure quality and performance. This includes visual inspection, automatic optical inspection (AOI), X-ray inspection, electrical testing and so on. Through these inspection and testing methods, problems in the production process can be effectively identified and eliminated to ensure that the product meets the design and quality standards.

 

Fifth. Quality management system: continuous terminal quality control and continuous improvement

To ensure the quality and performance of PCB boards, manufacturers should establish a comprehensive quality management system. Through the implementation of ISO 9001, ISO 14001, IATF 16949 and other international quality certification, not only to ensure that the company’s production processes and quality control system in line with international standards, but also to continuously improve and optimize the production process to improve product quality and performance. At the same time, regular training of employees to improve their skills and quality awareness is an important part of ensuring the quality and performance of PCB boards.

 

Sixth, environmental considerations: the implementation of green production strategy

In order to ensure the quality and performance of PCB boards at the same time, manufacturers should also pay attention to environmental protection, the implementation of green production strategies. This includes optimizing the production process, reduce waste and emissions of hazardous substances, the use of environmentally friendly materials, as well as the promotion of lead-free and halogen-free technologies. By implementing green production strategies, manufacturers can improve the environmental performance of their products while enhancing their corporate image and competitiveness.

Nine major quality problems and solutions of the PCB board

n the entire production process of the PCB circuit board, there are many quality control points. If it is not rigorous, the quality problem of the PCB line board is endless. This is also a headache, because there is only one of them, so big, so big, so big Most devices are not available. Next, introduce the 9 major quality problems and solutions of the PCB board.

1. [Layers]

Stratification is the difficulty of the boss of PCB, ranking first in common problems. The cause of it may be roughly as follows:
(1) Improper packaging or preservation, moisture;
(2) The preservation time is too long, exceeding the preservation period, and the PCB board is tide;
(3) Supplier’s materials or process issues;
(4) Design materials and copper surfaces are not well distributed.

 

2. [Poor weld]
Weldability is also one of the more serious issues, especially batch problems. The possible cause is plate surface pollution, oxidation, black nickel, nickel thick abnormalities, anti -welding SCUM (shadow), too long storage time, moisture absorption, PAD on the anti -welding, too thick (repair). The pollution and hygroscopic problems are relatively easy to solve, and other problems are more troublesome, and there is no way to find it through feeding inspection. At this time, it is necessary to pay attention to the process capacity and quality control plan of the PCB board factory. For anti -welding PAD and poor repairs, you need to understand the standards of PCB suppliers on the formulation of maintenance. Inspectors and inspectors have a good assessment system, and at the same time, it is clear that the dense area of the pads cannot be repaired.

 

3. [Board bending plates]
The reasons that may cause the plate bending plates are: supplier selection problems, abnormal production processes, poor control of heavy labor, improper transportation or storage, not strong enough design of the broken hole, and the differences in copper area of each layer are too large. In the last 2 points, the design of the design needs to be avoided in the early stage. At the same time, the PCB factory simulation stickers IR conditions can be required to test, so as not to occur in the back of the furnace. For some thin plates, you can need to add a wooden slurry plate to the packets when the packaging is used to avoid subsequent deformation. At the same time, add a fixture to prevent the device from overweighting the curved plate.

 

4, [scrape, dew copper]
Scratches and bronze are the defects that test the management system and execution of the PCB plant. This problem is not serious, but it will indeed bring quality concerns. Many PCB companies will say that this problem is difficult to improve. The author once promoted the improvement of scratches of many PCB factories, and found that many times it is not that it is not good, but whether to change it or not to change it. All PCB factories that seriously promote the project have improved significantly.

 

5. [Poor impedance]
Impedance is an important indicator of the radio frequency performance of the mobile phone board. Generally, the common problem is that the impedance differences between the PCB batches are relatively large. Since the current impedance test bar is generally on the side of the PCB, it will not ship with the board, so the supplier can pay the batch of impedance strips and test reports for each time they ship. Comparison data of the edge line diameter and the inner line diameter.

 

6. [BGA welding empty hole]
BGA welded cavities may cause poor main chip function, and may not be found in the test that hidden risks are high. So many patch factories now have X-Ray for inspection after the part. The cause of this kind of bad may occur is the residual liquid or impurities in the PCB hole, vaporization after high temperature, or poor laser hole type on the BGA pad. Therefore, many HDI boards now require electroplating pores or half -filled holes to avoid this problem.

 

7. [Foam/Show off for anti -welding]
Such problems are usually abnormal in the control of the PCB welding process, or the use of anti -welding ink is not suitable (cheap goods, non -chemical inks, not suitable for installing welded welds), or may be too high in patch and heavy work. To prevent batch problems, PCB suppliers need to formulate corresponding reliability test requirements and control them at different stages.

 

8. 【Poor Confucius】
Poor holes are mainly caused by insufficient technical capabilities of the PCB plant or simplified technology. Its manifestations are not full of plug holes. It may cause insufficient welding volume, short circuit with patch or assembly devices, and residual impurities in the hole. This problem can be found in the appearance inspection, so it can be controlled by the feeding inspection and requires the PCB plant to improve.

 

9. [Poor size]
There are many possible reasons for the poor size. It is easy to shrink in the PCB production process. Suppliers have adjusted the drilling program / graphics ratio / molding CNC program, which may cause problems such as biased bias and poor structural parts. Because it is difficult to check such problems, it can only be controlled by the supplier’s good process, so special attention needs to be paid to it when choosing the supplier.

Emphasizing quality control in PCB assembly is critical to improving product quality, reducing costs and protecting intellectual property. Therefore, we encourage our customers to select suppliers with strong quality control systems to ensure the reliability of their products.

At LST, we understand the importance of quality control in PCB assembly and are committed to providing our customers with high quality products. With our extensive experience in the field and state-of-the-art equipment, we can produce PCBs that meet the highest industry standards.