The transition to glass substrates is becoming the next critical technological battleground in advanced packaging for AI chips, with panel manufacturers racing to extend their large-format glass processing expertise into this emerging semiconductor packaging market. Recent analysis indicates that Innolux Corporation, BOE Technology Group, and AUO Corporation are each advancing along distinct strategic paths. However, the earliest timeline for mass production is estimated around 2028. Until then, the companies' core commodity panel businesses are expected to remain the primary driver of their fundamentals.

Current Leaders in the Field

Among the three companies, Innolux Corporation is currently viewed as the frontrunner. The company has reportedly completed the proof-of-concept (POC) phase for a glass core substrate project in collaboration with a major foundry, with further validation testing scheduled over the coming quarters. BOE Technology Group is pursuing a more vertically integrated approach, aiming to master the full manufacturing process for glass core substrates, including through-glass vias (TGVs) and build-up layers. If development proceeds as planned, BOE intends to invest approximately 5 billion Chinese yuan in 2027 to establish a production line with a monthly capacity of 15,000 panels (510mm×515mm), targeting mass production in 2028. These developments have fueled significant recent stock price gains for panel makers, with Innolux shares surging nearly threefold over roughly two months, far outpacing the broader Taiwanese market's gain of about 16%.

Technical Merits Fueling Market Optimism

Glass substrates are credited with several key advantages for advanced packaging, as outlined in a recent in-depth report. These include significant cost scaling benefits from larger panel formats, superior electrical properties that reduce signal loss, a closer coefficient of thermal expansion (CTE) match with heterogeneous materials to mitigate warpage, and higher mechanical strength to resist deformation during manufacturing and use. As AI chip package sizes continue to grow, panel makers' accumulated expertise in large-format glass processing aligns increasingly well with the technical demands of advanced packaging, prompting a market re-rating of these stocks. The report also notes that a more realistic timeframe for the mass production of glass substrates for high-performance computing (HPC) applications is between 2028 and 2029.

Detailed Strategic Paths of Key Players

Innolux's Leading Position

Innolux Corporation has been the most vocal and active investor in advanced packaging among the three over recent years. The company's role involves performing the TGV process on 510mm×515mm glass panels, which are then sent to Ibiden for ABF substrate processing, with final advanced packaging completed by the foundry partner. The key technical challenges lie in laser-induced etching for TGV formation and the subsequent copper plating process—steps not part of Innolux's standard panel production. The company is expected to require specialized equipment for glass core processing, with initial capital expenditure estimated between NT$20 billion and NT$30 billion. Revenue from packaging-related business is projected to reach around NT$20 billion by 2028, constituting approximately 6% of total revenue. While its rating was maintained, its price target was raised, with analysts noting the current valuation, at historical highs, presents a less favorable risk-reward profile.

BOE's Integrated Ambition

As the world's largest panel maker, BOE Technology Group is pursuing a path of vertical integration, aiming to control the entire glass core substrate manufacturing process rather than focusing on a single processing step. The company began research into glass core substrate technology in 2020, currently operates a pilot line, and is conducting validation work with domestic and international IC design houses. Its projected revenue from advanced packaging is estimated at about 5 billion Chinese yuan by 2028, representing roughly 5% of total revenue. BOE received an upgraded price target, with analysts viewing its current valuation as reasonable and offering the most attractive risk-reward ratio among the three, supported by an estimated 5% to 8% ROE from 2026 to 2028.

AUO's Alternative Focus

AUO Corporation is charting a different course in advanced packaging, currently focusing not on HPC but on low-earth orbit (LEO) satellite antenna modules and co-packaged optics (CPO) modules. For LEO antennas, AUO plans to use glass as a substrate to carry antenna patterns and RF components, integrating them into vehicle sunroofs. For CPO modules, the company is collaborating with partners like Ennostar and Tyntek on a Micro LED-based CPO architecture, aiming for lower-cost, lower-power short-distance data transmission, with glass again serving as the substrate material. Management has stated these initiatives are progressing but has not provided a specific timeline for revenue contribution. Consequently, AUO's business timeline is considered the least visible among the three, and its forecasts do not currently include revenue from advanced packaging. Its price target was also raised, but it maintains the lowest valuation multiple of the group, coupled with the highest uncertainty regarding its new business schedule.

Valuation Considerations and Market Timing

Despite the promising technical outlook for glass substrate packaging, market sentiment needs to be calibrated against the commercial timeline. Supply chain checks suggest mass production is unlikely to commence before 2028. Until then, commodity panel businesses will continue to dominate the revenue mix for these companies, accounting for 40% to 50% of revenue for Innolux and AUO, and 70% to 80% for BOE. Concurrently, the current TV panel price upcycle is assessed to be nearing its end, with prices expected to begin a downward trend starting in Q3 2026, although major panel makers are anticipated to maintain relatively disciplined capacity management. This implies that against a backdrop of potential price pressure in their core commodity panel businesses, the ability of these three companies to execute their advanced packaging mass production plans on schedule will be a critical variable in sustaining their current elevated valuations.