My latest supply chain checks indicate that Nvidia has begun testing glass-free copper-clad laminate (CCL) based primarily on hydrocarbon (HC) resin as a replacement for glass-free PTFE-based CCL tested previously, paired with glass-free HC-based PP. The goal is to determine whether this material combination can meet the switch tray PCB requirements for Rubin Ultra NVL576, an eight-rack interconnected solution expected to enter mass production in 2H27.

Preliminary tests conducted as part of efforts to improve PCB manufacturability show that glass-free HC CCL meets the switch tray’s high-frequency electrical requirements. Its electrical performance trails that of the original PTFE solution but exceeds that of M9-class solutions and even surpasses M10’s stated specifications. These results do not represent a final material selection, but they indicate that NVIDIA continues to seek higher PCB manufacturing yields and greater production efficiency while meeting electrical requirements.

1. Key Takeaways and Analysis

(1) Previous NVL576 switch tray tests used glass-free PTFE CCL paired with glass-free HC PP. The latest round replaces the PTFE CCL with glass-free HC CCL while retaining the same HC PP part number.

(2) Shengyi Technology is currently the leading supplier in the NVL576 switch tray material evaluations. The materials involved are SG5300N (glass-free PTFE CCL), SG1030N (glass-free HC CCL), and SIF09 (glass-free HC PP).

(3) The primary objective of testing glass-free HC CCL as a replacement for glass-free PTFE CCL is to determine whether PCB manufacturing yields and production efficiency can be improved while still meeting high-frequency electrical requirements.

(4) To further improve PCB manufacturability, subsequent tests may also evaluate replacing glass-free HC PP with woven-glass-reinforced HC PP. The challenge is whether the glass-reinforced material can still meet signal integrity and 0.4 dB/in loss requirements.

(5) Notably, both SG1030N and SIF09 still contain small amount of PTFE, although HC is the primary material. These tests therefore do not represent a complete shift away from PTFE. Rather, they involve adjusting the primary resin system and material combination to balance high-frequency electrical performance with PCB manufacturability.

2. Conclusions

(1) The long-term trend toward broader use of PTFE in advanced PCB materials, including CCL and PP, remains clear. However, the pace of shipment growth over the next two years remains uncertain. Key variables include NVL576 switch tray PCB’s final material selection, NVL576 adoption rate, and development progress on Kyber-like rack designs that use orthogonal backplanes.

(2) HC use in advanced CCL and PP continues to expand. Beyond NVL576 switch trays, near-term growth drivers include the production ramp of M9-class materials beginning in 4Q26, followed by the adoption of M10-class materials.

(3) Once specifications are finalized and mass production begins, it's expected that Shengyi Technology to accelerate sourcing from Chinese HC suppliers. These include existing suppliers such as Dongcai and Shengquan, as well as potential ones such as GCH Technology. This should help alleviate supply shortages and optimize its cost structure.