In today’s high-power electronics landscape, standard PCBs are no longer sufficient for demanding applications. Whether it’s electric vehicles, industrial automation, or power conversion systems, the need for durability, high current capability, and excellent heat dissipation has given rise to a specialized solution: super thick PCBs. These boards, often overlooked in general PCB discussions, are the backbone of robust electrical systems where failure is not an option. In this article, we’ll dive deep into everything you need to know about super thick PCBs, from how they’re made to what they cost in 2025.
1. What Are Super Thick PCBs?
Super thick PCBs refer to printed circuit boards with exceptionally thick copper layers—typically more than 3 oz (about 105 μm) per square foot. Some designs use 6 oz, 10 oz, or even up to 20 oz copper. These PCBs are essential for managing high current and high power in compact spaces. Unlike regular boards, which have copper thicknesses of 1 oz or less, super thick PCBs are engineered for extreme reliability and mechanical endurance.
2. Key Advantages of Super Thick PCBs
High Current-Carrying Capacity
The thicker the copper, the higher the current it can safely conduct. This makes super thick PCBs ideal for power modules and motor control systems.
Improved Thermal Management
Excessive heat can be dissipated more efficiently, reducing the risk of overheating and increasing system longevity.
Enhanced Mechanical Strength
These PCBs are more resistant to vibration, bending, and thermal cycling—critical in automotive and aerospace environments.
Long-Term Durability
Super thick PCBs maintain performance under high stress, ensuring long-term operational stability.
3. Common Applications of Super Thick PCBs
Power Supply Systems
High-current DC/DC converters and power distribution units (PDUs) often rely on thick copper boards.
Electric Vehicles (EVs)
Battery management systems and motor control units benefit from thick copper layers for safe energy delivery.
Industrial Automation
Robotics, motor drives, and programmable logic controllers (PLCs) use super thick PCBs for reliability under continuous operation.
Military and Aerospace
Withstand extreme environments, from temperature fluctuations to mechanical shock.
LED Drivers
Improve current handling and heat spreading in high-power lighting applications.
4. Material Selection for Super Thick PCBs
FR4 Substrate
Most common base material, good for general applications with moderate thermal demands.
High-Tg FR4
Offers better thermal stability, crucial for high-temperature environments.
Ceramic or Aluminum Substrates
Used in extreme thermal or high-frequency situations.
Copper Thickness Options
- Standard: 1 oz – 2 oz
- Super Thick: 4 oz, 6 oz, 10 oz, up to 20 oz
- (1 oz ≈ 35 μm thickness)
5. Manufacturing Challenges and Solutions
Etching and Plating
Thick copper requires precision etching and electroplating to maintain trace definition and avoid over-etching.
Drilling Difficulties
Deeper holes and stronger mechanical stress demand specialized drilling tools and techniques.
Lamination Control
Proper pressure and heat distribution are crucial to avoid delamination during multilayer bonding.
Inspection and Quality Assurance
AOI (Automated Optical Inspection) and cross-section analysis are used to verify internal copper integrity.
6. Design Guidelines for Super Thick PCBs
Minimum Trace Width
Designers must increase trace width to accommodate higher current—often above 10 mm for high-load circuits.
Via Design
Multiple vias or via-in-pad design help distribute current evenly and reduce resistance.
Thermal Relief Pads
Used to balance heat dissipation without compromising solderability.
Layer Stack-Up
Strategic layering helps reduce internal resistance and thermal accumulation.
7. Super Thick PCB Pricing: What to Expect in 2025
The cost of super thick PCBs can range from $80 to $300 per square meter, depending on specs like copper weight, layer count, and complexity. Below are typical pricing examples:
- 2-Layer, 4 oz Copper, FR4 (100 pcs): $90–$120/m²
- 4-Layer, 6 oz Copper, High-Tg FR4 (50 pcs): $160–$220/m²
- Custom 10 oz Copper, 2-Layer, Ceramic Substrate (Prototypes): $250–$300/m²
Cost Influencers:
- Copper thickness and material type
- Drilling precision and plated via count
- Board size and overall surface area
- Quantity and lead time (rush orders can add 20–30%)
At KingSunPCB, we offer competitive bulk pricing and full support for custom super thick PCB projects, including free DFM checks and engineering feedback.
8. How to Choose the Right Manufacturer for Super Thick PCBs
Certifications
Look for ISO9001, UL, and IATF16949 (for automotive) to ensure quality assurance.
Technical Capability
Ensure the factory can handle >6 oz copper consistently and perform impedance control when needed.
Rapid Prototyping Support
Short-run production capabilities help validate designs before scaling up.
Customer Support and Logistics
A reliable PCB partner should offer fast response times, online engineering support, and global delivery options.
9. Frequently Asked Questions (FAQ)
Q1: What’s the thickest copper you can use in a PCB?
Most manufacturers offer up to 20 oz, though 10 oz is a practical limit for many standard processes.
Q2: Can super thick copper be used in multilayer PCBs?
Yes, but layer stacking must be carefully engineered to maintain bonding and electrical integrity.
Q3: How does thick copper affect signal performance?
It can slightly reduce high-frequency performance due to increased conductor thickness but improves power delivery.
Q4: What’s the lead time for super thick PCBs?
Typical lead time is 7–15 working days, depending on the design complexity and order size.
10. Conclusion: Is a Super Thick PCB Right for Your Project?
If your project involves high current, extreme heat, or mechanical stress, a super thick PCB could be your ideal solution. These boards deliver unmatched power handling and durability, but require thoughtful design and expert manufacturing.
Looking for a reliable super thick PCB supplier? KingSunPCB offers expert engineering support, advanced manufacturing capabilities, and competitive global pricing. Contact us to get a custom quote within 24 hours.