Glass substrates offer numerous superior properties. They possess strong thermal stability, allowing their coefficient of thermal expansion to be precisely set between 3-5 ppm/°C through composition control. This matches the thermal expansion coefficient of silicon chips, thereby maintaining connection integrity. Glass substrates also demonstrate exceptional dimensional stability, with warpage potentially reduced by over 50% compared to traditional organic substrates. Their excellent insulating properties result in significantly lower dielectric loss in high-frequency ranges compared to silicon or organic materials, markedly reducing power leakage and signal distortion when signals pass through the substrate. Furthermore, replacing costly and structurally complex silicon interposers with glass substrates can substantially lower the cost of panel-level substrates, offering significant economic benefits.
The application of glass substrates in the field of advanced packaging is expected to gradually mature, with leading manufacturers accelerating their deployment. Some investors believe the technological maturity of glass substrates in chip packaging is limited. However, it is argued that their application in advanced packaging is poised for gradual maturation. Glass substrates hold broad application prospects in multiple areas, including AI accelerator and CPU packaging substrates, CPO, CoPoS technology, and Mini/Micro-LED packaging. Leading enterprises are accelerating their layouts. In January 2026, Intel Foundry showcased its EMIB packaging technology integrated with a 'Thick Core' glass substrate at Japan's NEPCON exhibition. Intel has accumulated over 1,000 inventions related to glass substrate architecture, processes, materials, and equipment. SKC and its subsidiary Absolics are expected to commence the world's first commercial mass production of glass substrates by the end of this year, with prototype products undergoing performance testing by leading companies such as AMD and Amazon Web Services. TSMC is advancing CoPoS technology, aiming to reduce costs and improve production capacity efficiency through panel-level packaging to meet the rapidly growing demand from AI chip customers. In the medium to long term, the adoption of glass substrates and glass interposer solutions may become an important evolutionary direction. In 2024, Corning demonstrated a CPO design solution based on glass substrates.
The penetration rate of glass substrates in the HDD field is expected to continue increasing. Some investors have limited understanding of technological evolution in the HDD sector, overlooking the growth potential for glass substrates. Glass substrates can be used as recording media in HDDs. As demand for high-capacity storage remains strong, the proportion of HAMR technology in solid-state drives is expected to rise continuously. HAMR technology employs a new type of medium magnetic technology on each disk, enabling data bits to become smaller and denser than before while maintaining magnetic and thermal stability. The high-temperature characteristics of HAMR technology may make heat-resistant glass substrates a crucial alternative to replace traditional aluminum platters. According to QYResearch, the global market size for glass substrates used in HDDs was $890 million in 2024. Currently, the sole producer of glass substrates for HDDs globally is the Japanese company Hoya. Looking ahead, domestic manufacturers are expected to enter the market. According to Lens Technology's announcement, the company is collaborating with a leading global HDD manufacturer on the development of glass substrates for high-density storage hard drives, with 2026 being a critical stage for verification and small-scale trial production.
Glass substrates exhibit excellent performance, opening up application space in downstream sectors such as advanced packaging and storage.