Glass substrates, long discussed as a potential replacement for organic substrates in advanced semiconductor packaging, are now drawing serious interest from major technology companies. Reports from ETNews and Commercial Times suggest that Apple and Tesla are evaluating the integration of the technology into next-generation chips, with potential applications in Tesla's autonomous driving platforms and Apple's in-house silicon for devices such as iPhones and MacBooks.

Glass substrates offer several advantages over organic cores, including higher density, superior flatness, and greater stability. These features enable larger, denser multi-die packages with shorter signal paths, making the technology attractive for AI accelerators, server processors, and large-die applications that demand high data bandwidth. Industry sources note that adoption could be crucial for boosting performance in advanced products, particularly as organic substrates face increasing challenges such as warpage and signal bottlenecks at larger sizes.

While no company has yet achieved stable mass production, momentum is building. Taiwanese substrate makers such as Unimicron and Nan Ya PCB have reportedly provided trial samples to customers and are preparing for small-scale runs with shared development costs and design feedback from end clients. Meanwhile, Absolics, a subsidiary of SKC, is ramping up output in a bid to become the first to commercialize glass substrates.

Despite their promise, glass substrates remain difficult to manufacture compared with mature ABF substrates. They are prone to cracking during drilling, and downstream processes such as build-up layering and solder mask application require specialized adjustments due to material differences. These challenges, alongside supply chain integration and cost structure, remain key hurdles before large-scale commercialization.

Still, with industry heavyweights including Intel, AMD, Samsung Electronics, Amazon, and Broadcom also exploring the technology, the entry of Apple and Tesla has been seen as a turning point that could accelerate investment and validation. Analysts suggest that once technical maturity is reached, glass substrates could reshape the substrate landscape, paving the way for more powerful AI-driven applications.