Factors Affecting the Cost of Flexible PCB Manufacturing

FPC flexible circuit boards are widely used in various fields such as mobile devices, medical equipment, and aerospace. The price of flexible circuit boards on the market varies greatly. In this article, we will delve into the factors that contribute to the diversity in pricing, helping you better understand this phenomenon.

12 Factors Affecting PCB Manufacturing Costs

Several factors drive the cost of PCB manufacturing. Understanding the stages of production and processing can help you make cost-effective decisions, ensuring product quality while saving money.

  1. PCB Size
    The size and shape of a PCB directly impact cost. Expanding the size of the PCB requires more materials and time to produce the final product, leading to higher costs. The price of a PCB increases proportionally with its surface area, allowing you to calculate the additional expense when exceeding standard dimensions.

  2. Efficient Use of Materials
    Efficient material usage is closely related to size and spacing. Choosing a smaller PCB uses fewer materials, making it a more cost-effective option. However, even with larger PCBs, you can reduce waste by efficiently using available space, only using the materials necessary, thus lowering material costs. Finding an arrangement that optimizes your space and size ensures you only use what’s required.

  3. Number of Layers
    The cost of adding extra layers increases for several reasons. More layers require additional materials, and the extra etching and bonding steps take more time. Additionally, adding more layers raises the probability of defects during testing, which manufacturers consider when quoting prices for multilayer boards. Each layer must be inspected, further adding to the overall cost.

  4. Complexity
    The further your PCB design strays from standard and traditional board technologies, the higher the cost. More complex configurations and designs require additional time and steps for assembly. While a simple PCB might require only one processing step, a complex one could demand three to four extra procedures, such as laser drilling. Specialized personnel or equipment may also be needed, further driving up costs.

  5. Material Selection
    Depending on the materials you choose, prices can fluctuate. Some materials offer better cost-performance ratios, allowing you to save on PCB production. While high-quality materials may be necessary for specific board functions, selecting those that best align with your budget can help reduce costs.

  6. Trace Width and Spacing
    PCB traces are essential as they determine the board’s electrical carrying capacity. However, how you design the traces and their relationship to available space can influence the price. Tighter traces are more challenging for manufacturers, leading to increased service costs.

  7. Hole Size and Quantity
    Many hole-related factors can increase your PCB manufacturing costs, with hole size being the most common. Smaller holes are more challenging and require specialized training and tools, which increases expenses. When holes reach a certain size, lasers are necessary for precision. Additionally, a higher number of holes requires more manufacturing time, further driving up costs. If there are multiple layers or thicker materials, expect higher costs to accommodate the additional manufacturing time.

  8. Impedance Control
    Like tight traces, controlled impedance demands very specific or uniform trace width and spacing in both design and production. Various factors in these processes contribute to higher costs, from the specific materials required to achieve desired results to the necessary testing procedures.

  9. Tight Tolerances
    Tight tolerances in PCB design automatically increase the board’s complexity, which leads to higher costs. Additionally, tight tolerances can sometimes result in assembly or fitting issues, adding troubleshooting costs due to potential misalignments.

  10. Copper Thickness
    Copper foil thickness is closely related to efficient material use. Thicker copper foil is more expensive and presents additional challenges and costs. You may need to use more prepreg materials to fill gaps between the copper layers during processing. Additionally, because thicker copper is heavier, you may face higher shipping costs.

  11. Solder Mask, Silkscreen, and Carbon Ink
    When designing your PCB, consider the production steps your manufacturer will need to complete. Solder mask, silkscreen, and carbon ink all require separate processes, which involve more time. If these processes require specialized equipment or tools, costs will change accordingly. For instance, opting for higher-quality or thicker solder mask materials will raise the price.

  12. Surface Finish
    The cost of a PCB can vary depending on the surface finish you select. Standard and basic finishes like OSP and HASL are more cost-effective while still providing good solderability. However, other finishes can lead to increased prices. LF HASL, Imm Ag, Imm SN, and ENIG vary in cost, with LF HASL being the most affordable and ENIG the most expensive. Additionally, prices change based on the number of layers required by each material. Choosing a more economical surface finish can help lower PCB manufacturing costs.

How to Reduce the Cost of Flexible PCB Manufacturing

In the design and manufacturing process of electronic products, PCBs serve as core components, and engineers or manufacturers often face demands such as “cost reduction or cost control.” So how can we achieve this? Here are some strategies:

  1. Accurate Selection of PCB Materials

    Clarify Requirements: First, based on product design specifications, identify the type of PCB material, the number of layers, and performance parameters required. Avoid unnecessary costs caused by over-design.

    Balance Between Brand and Quality: For multilayer boards or high-demand orders, prioritize well-known brands like Kingboard, Shengyi, and Nanya to ensure stable quality. For simpler applications or cost-sensitive projects, choose cost-effective materials that meet basic performance requirements.

  2. Optimize Drilling Design and Process

    Reduce the Number of Holes: By optimizing circuit design, reduce unnecessary vias and through-holes, directly lowering drilling costs.

    Set Hole Sizes Rationally: Choose appropriate hole diameters based on actual needs, avoiding the pursuit of excessive precision that increases difficulty and cost.

    Use Advanced Equipment: Select high-precision, high-efficiency drilling machines to improve processing efficiency and reduce defect rates.

  3. Control Process Costs Reasonably

    Process Selection: Based on the specific needs of the PCB, choose the most cost-effective surface treatment. For example, in non-high-frequency and non-high-reliability applications, prioritize OSP (Organic Solderability Preservative) to reduce costs.

    Process Combination Optimization: When multiple processes are required, carefully evaluate the necessity and cost-effectiveness of each to avoid unnecessary process stacking.

  4. Manage Copper Thickness and Layer Count

    Select Copper Thickness Based on Need: Choose the appropriate copper thickness according to current carrying capacity and signal transmission requirements, avoiding unnecessary waste.

    Optimize Layer Design: By planning the number of layers reasonably, reduce unnecessary layers to lower material costs and processing complexity.

  5. Control Molding and Testing Costs

    Distribute Molding Costs: For large-scale production, consider increasing production batches to spread the mold costs, reducing the cost per unit.

    Adjust Testing Strategy: Use flying probe tests for prototypes or small batches, and consider investing in test jigs for mass production to save on long-term testing costs. Additionally, optimize testing procedures to improve efficiency and reduce time and labor costs.

Conclusion
Reducing the cost of flexible PCB manufacturing requires a comprehensive approach, including optimizing design, material selection, process improvements, procurement management, cost control and monitoring, as well as technical innovation and R&D. By applying these strategies effectively, manufacturers can significantly reduce production costs, enhancing competitiveness and profitability.