High-Frequency and High-Speed PCB Material Selection Guide: RO4350B, Megtron 6, TU-872
With the rapid development of 5G, AI servers, optical modules, and data center switches, PCB material performance—particularly in terms of loss, stability, and manufacturability—has become a critical factor for design and production. RO4350B, Megtron 6, and TU-872 are the three most commonly used high-frequency, high-speed materials on the market. However, they have different applications, and selecting the wrong material may result in insufficient performance or increased costs.
Material Overview
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Megtron 6: Ultra-low loss (Df≈0.002), suitable for 56–112G high-speed links and long-distance PAM4 backplanes, such as AI servers and 800G/1.6T switches.
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RO4350B LoPro: Excellent high-frequency stability, ideal for RF antennas, millimeter-wave applications, and mixed high-speed + RF boards.
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TU-872 SLK: Moderate loss and easy to process, suitable for 10–28G high-speed links, optical modules, and enterprise switches, balancing performance, cost, and manufacturability.
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TU-768: Lower-cost version, suitable for 2.5–10G or cost-sensitive projects.
Key Parameter Comparison (Typical Values at 10 GHz)
| Material | Df | Dk | Processing Difficulty | Cost | Domestic Lead Time Stability |
|---|---|---|---|---|---|
| Megtron 6 | 0.0018–0.0023 | 3.1–3.3 | High | Very High | Moderate |
| RO4350B LoPro | 0.0031–0.0037 | 3.48–3.66 | Medium-High | Medium-High | Good |
| TU-872 SLK | 0.0065–0.0075 | 3.8–4.0 | Low | Medium-Low | Excellent |
Selection Logic
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Ultra-high-speed 56–112G links → Megtron 6/7 or Tachyon series; loss has a significant impact on signal integrity.
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High-speed + RF mixed boards → RO4350B LoPro; balances high-frequency performance and cost.
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10–28G high-speed equipment → TU-872 SLK; meets signal requirements and allows better cost control.
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2.5–10G or extremely cost-sensitive projects → TU-768; sufficient performance at lower cost.
Practical Experience
Over the past three years, the company has delivered numerous 10–112G high-speed and high-frequency mixed projects:
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For 10–28G projects, most used TU-872 SLK, accumulating experience in impedance control and multi-layer board consistency.
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For RO4350B LoPro + ultra-low-loss material mixed-lamination projects, the company helped clients achieve a balance between high-speed performance and cost.
Conclusion
There is no universal material—only the most suitable one. The core principles for material selection are: speed requirements + RF requirements + cost budget + production lead time. Correct selection of high-frequency, high-speed materials can improve signal integrity, manufacturability, and production yield.