Panel Makers Enter Glass Substrate Advanced Packaging, Reshaping Semiconductor Packaging Technology

As AI chips evolve toward larger dimensions, higher compute power and denser interconnect, traditional organic substrates are approaching their performance limits, making glass substrate advanced packaging a new focus of competition in the semiconductor display industry. Multiple panel makers have launched cross-sector initiatives, adopting glass substrate packaging as a future technology direction, with process validation and production line construction gradually advancing.

Zhao Jun, chief executive of TCL CSOT, said the company has formed a dedicated team to advance validation of key glass substrate packaging processes, planning to showcase samples and set up a pilot line in the second half of 2026. BOE invested RMB 993 million in 2024 to build a glass substrate packaging carrier board test line, which has already sent samples to some domestic customers; some customers have passed concept certification and entered technical testing. Tianma has built the MPG multi-project glass substrate technology platform, listing advanced packaging as one of its key enablement directions and carrying out technology development and cooperation across multiple non-display application areas.

Compared with traditional organic substrates, glass substrates offer a thermal expansion coefficient closer to that of silicon chips, higher flatness, lower dielectric loss and stronger insulation, helping to alleviate problems such as warpage in large-size packaging, high-frequency transmission loss and interconnect density constraints. Display panel manufacturing and semiconductor advanced packaging share synergies in core processes, including large-size glass substrate handling, thin film deposition, photolithography, etching and automated transfer, providing technical support for panel makers' cross-sector entry.

Despite rising industry enthusiasm, glass substrate advanced packaging still has a considerable distance to go before large-scale commercialization. Current technical difficulties center on TGV copper filling, stress control in multi-layer film structures and deep processing of glass substrates. The maturity of upstream materials and equipment needs improvement, and high-end TGV glass raw sheets remain dominated by overseas manufacturers. BOE disclosed that its glass substrate packaging carrier board test line business has not yet achieved batch production or mass-production revenue, and the test line yield rate has not reached mass-production levels, leaving uncertainty over scaled application.