Glass substrates are gaining momentum: Nvidia officially enters the race, which giant can seize the opportunity first?

Nvidia has placed a timeline of “development must be completed within two years” on the desks of substrate manufacturers in South Korea, Japan, and Taiwan (China).

According to South Korean media reports, Nvidia has requested that substrate manufacturers in South Korea, Japan, and Taiwan (China) finish developing glass substrates within two years, aiming for implementation before 2028. This timeline shortens the industry’s usual pace by about 60%, and directly moves a material route that was originally confined to the laboratory to the countdown for mass production.

Three things need to be clarified. First, what glass substrates are replacing is not just one material, but two different things—Intel's glass core substrate replaces the underlying ABF organic carrier board, while TSMC's CoPoS glass interposer replaces the upper silicon interposer; their process architectures, customers, and timelines are all different.

Second, there is only one real bottleneck: yield. Glass substrates offer significant improvements over traditional substrates in terms of thermal expansion coefficient, dielectric loss, and processable size, and there is no longer any debate about these metrics. The controversy lies in the yield rates for multilayer stacking—the industry mass production lines currently stabilize at 60%—75%, while the global average yield for high-density substrates with more than 8 layers is less than 40%. Equipment and demand do not pose constraints; yield is the only variable that can change the pace.

Third, the distribution of industry chain profits is seriously misaligned with market attention. Upstream specialty glass wafers alone account for more than 60% of the finished glass substrate’s cost, and over 90% of the global high-end wafer market share is controlled by Corning, AGC, and Schott; by contrast, domestic substitution progress in the midstream TGV deep processing segment is actually the fastest.