Glass substrates are the trend of the general trend

Glass is becoming a platform for sourcing in the end markets dominated by data centers and telecommunications. In the data center, it ensures two key packaging carriers: chip structure and optical input and output (I/O). Low coefficient of thermal expansion (CTE), deep ultraviolet (UV) glass carriers make hybrid bond preparation and 300 mm thin wafer backs standardized processes. As switch and accelerator body sizes move beyond the wafer stepper field, panel carriers become critical. The market size of GCS substrates is expected to reach US$460 million in 2030, with optimistic forecasts for widespread adoption in 2027-2028, while glass interposers are conservatively forecast to reach more than US$400 million by 2030, while stable glass carrier applications represent a market size of US$500 million.

Glass in advanced packaging is now a platform business, not a component business. For glass carriers, the revenue stream has shifted from plate price to one-way price, and the economics depend on the number of reuses, laser and UV debonding yields, yields, and edge damage avoidance. This provides short-term benefits for suppliers offering CTE-grade series, bundle owners who sell carriers + adhesives, LTHC+ debonding as a single qualified stack, and regional recycling suppliers with optical quality assurance. Companies with deep glass expertise (e.g., Plan Optik's model of high flatness, controlled transmission and well-designed carrier bundling at the edges) are in the best position. The glass core substrate converts display panel production capacity into profit by increasing TGV (ultra-large aperture wind tunnel) + fine RDL (rewiring layer) + additive process. The winners occupy key interfaces: high-yield TGV drilling, etching technology, void-free copper filling, adaptive overlay panel lithography, 2/2 μm and panel handling technology with controlled warpage. Substrate manufacturers and OSAT manufacturers working with display glass manufacturers are turning area capacity into cost advantages for large-format packaging.

Glass has evolved from a simple carrier to a complete material platform for advanced packaging, aligning with megatrends such as chip integration, panelization, vertical integration, and hybrid bonding, while tightening mechanical, thermal, and cleanliness budgets. As a carrier (wafer and panel), clear, low coefficient of thermal expansion (CTE) glass enables alignment and laser and UV debonding of the carrier with minimal stress, resulting in higher yields for sub-50 micron wafers, backside pipelines, and reassembled panels, as well as multi-purpose economics. As a glass-core substrate, it replaces the organic core and supports panel-level manufacturing: TGV provides dense vertical power, signal transmission, SAP RDL breaks 2/2 micron, has a flat substrate that reduces warpage with CTE adjustment, and transparency prepares co-packaged optics and solves heat dissipation with copper plane, stitched vias, BSPDN, and double-sided cooling technology. As a glass interposer, it wins in two modes: passive mode, where a very large 2.5DAI with HPC and switching structures achieve routing density and bump count at a cost and area that is hard to match, and active mode, where in-substrate SIW, filters, antennas, and metallized trenches or lasers write waveguides to fold the RF chain and bring optical inputs and outputs to the edge with low loss.

According to Yole Group's latest analysis, glass materials are now at the heart of the semiconductor packaging revolution, driven by megatrends such as artificial intelligence, high-performance computing (HPC), 5G and 6G connectivity, and co-packaged optics. Analysts highlight that glass's unique properties, including low coefficient of thermal expansion (CTE), exceptional dimensional stability, and optical clarity, make it an indispensable material for meeting the mechanical, electrical, and thermal performance needs of next-generation packaging.
Yole Group said the data center and telecommunications industries are the main growth engines driving the application of glass in the packaging sector, and automotive, defense and high-end consumer electronics have also brought additional growth momentum. These industries are increasingly relying on chip integration, hybrid bonding, and panel-level manufacturing, where glass offers both performance and cost advantages. The analysis also points to emerging supply chains in Asia, particularly China, South Korea, and Japan, as key factors in scaling up production and strengthening the global advanced packaging glass ecosystem. (Excerpted from Yole).