Semiconductor glass substrates are drawing attention as a key material that can solve problems in the packaging domain, which has hit technical limits in the age of artificial intelligence (AI). Major semiconductor manufacturers, including Samsung Electronics, TSMC, Intel, and AMD, are reviewing the application of glass materials to packaging substrates to increase integration density. The aim is to boost AI chip efficiency by using semiconductor glass substrates, dubbed a "game changer." Some project that AI chips with glass substrates could enter the commercialization stage as early as 2028.
Semiconductor glass substrate manufacturing corporations are said to be moving in earnest to build a mass production system. In Korea, SKC (subsidiary Absolics), Samsung Electro-Mechanics, and LG Innotek have thrown their hats in the ring to commercialize semiconductor glass substrates. However, the current stage of business development varies by corporation. SKC is furthest ahead, with Samsung Electro-Mechanics and LG Innotek in pursuit to close the gap.
According to the industry on the 14th, as early as next year, "early mass-produced" semiconductor glass substrates made by Korean corporations are expected to emerge. SKC and Samsung Electro-Mechanics are currently sending prototypes to customers and conducting tests. These corporations have set plans to start mass production systems in 2026–2027 and to enter a full ramp-up (volume increase) phase in 2027–2028. According to market research firm MarketsandMarkets, this market is expected to reach $8.4 billion (about 11.6 trillion won) in 2028. That would be about 18% growth from $7.1 billion (about 9.8 trillion won) in 2023.
◇ Why "semiconductor glass substrates" are on the rise
The need for semiconductor glass substrates has grown alongside improvements in AI performance. As AI services proliferate, more high-efficiency, high-integration, high-performance semiconductors are needed to run them. The performance of AI chips is related to the size of the semiconductor package substrate. Generally, package substrates with a width and length of 100 mm have been used, but sizes of 140 mm or larger are required for AI and server applications. The problem is that packaging substrates made of plastic (organic) materials, which are widely used today, warp as they get larger. Such shape deformation causes semiconductor performance degradation.
Intel, which has been conducting research and development (R&D) since the 2010s, has released findings that replacing the core layer of a semiconductor packaging substrate with glass could increase the width and length to 240 mm. Intel's view is that glass substrates, with a higher modulus (a physical quantity indicating a material's strength and elasticity) than conventional organic materials, are suitable for implementing high-performance chips.
A semiconductor substrate connects high-performance chips such as a central processing unit (CPU) and a graphics processing unit (GPU) to the mainboard (motherboard) inside a device. In the case of FC-BGA, a substrate used in today's high-performance AI servers, the application of chiplets (a technology that splits high-performance semiconductor functions into multiple parts and then combines them) and the increase in input/output (I/O) terminals have expanded the number of layers to as many as 40. FC-BGA used in general PCs is around 10 layers. To meet AI performance, ultra-fine circuits that organically consolidate these parts must be implemented, and glass has advantages over organic materials thanks to its higher surface flatness and lower coefficient of thermal expansion. Another reason semiconductor glass substrates are attracting attention is their resistance to deformation even when mounted in AI servers that repeatedly cool and heat.
Semiconductor glass substrates have many advantages, but they are not easy to develop. While they are resistant to deformation from external forces, they possess "brittleness," meaning they break easily beyond a certain level. This also means they are vulnerable to the more frequent "drilling" processes (making microscopic holes in each substrate to consolidate interlayer electrical signals, etc.) involved in making AI chips with increased layer counts.
SKC, Samsung Electro-Mechanics, and LG Innotek are developing technologies that address these issues with glass substrates while leveraging their strengths. They are also prioritizing securing technology in the FC-BGA field, which is among the most marketable of glass substrate applications. The aim is to switch the FC-BGA core layer from plastic to glass, increase substrate area and layer count, and deliver results in the AI market.
◇ SKC nearing mass production, Samsung Electro-Mechanics completes verification, LG Innotek moves to secure technology
In 2021, SKC formed the joint venture "Absolics" with Applied Materials, considered the world's largest semiconductor equipment corporation, and has been expediting its entry into the semiconductor glass substrate market. Shortly after its launch, Absolics unveiled a glass substrate prototype for supercomputers, drawing industry attention.
In the first half of last year, Absolics built the world's first semiconductor glass substrate production facility in the state of Georgia in the United States, and is now regarded as the closest among domestic corporations to commercialization. Prototypes produced there have reportedly been sent to AMD and Amazon Web Services (AWS) for performance evaluation.
Absolics is targeting next year for mass production of semiconductor glass substrates and is proceeding with related steps. Yoo Ji-han, SKC's chief financial officer (CFO), said in the third-quarter earnings release this year, "At the Georgia plant, we produced mass production samples of semiconductor glass substrates this quarter and began customer certification procedures," and added, "We have confirmed very positive simulation evaluation results and, in consultation with customers, are working toward commercialization next year."
Early this month, SK hynix Executive Vice President Kang Ji-ho, "formerly of Intel," was appointed the new CEO of Absolics. Industry watchers say this reflects the will to achieve early commercialization and secure market leadership, given that SK Group Chairman Chey Tae-won is personally overseeing the semiconductor glass substrate business.
Samsung Electro-Mechanics is closely trailing SKC. Since last month, it has been reviewing the establishment of a joint venture (JV) with Japan's Sumitomo Chemical Group to manufacture glass core, a key material for glass substrates. Through this company, it aims to begin mass production of glass substrates in 2027. It is also sending prototypes produced on a pilot line built at the Sejong site to customers for performance verification. The prototypes have reportedly been sent to AMD and Broadcom.
Samsung Electro-Mechanics also recently made personnel moves to strengthen the glass substrate business. It appointed Vice President Joo Hyuk, head of the Central Research Institute, as head of the Package Solution Business Unit in charge of semiconductor substrates. After stints at Samsung Electronics' System LSI Division and SAIT (formerly Samsung Advanced Institute of Technology), Joo moved to Samsung Electro-Mechanics at the end of 2023 and has led semiconductor glass substrate R&D. Earlier, in August, Samsung Electro-Mechanics hired Vice President Kang Doo-an, a semiconductor packaging expert with more than 17 years at Intel, as a senior engineer.
As a latecomer, LG Innotek has its semiconductor glass substrate institutional sector under the chief technology officer (CTO). It has reportedly set up equipment for prototypes at its R&D center. The company has established a mid-to-long-term strategy to secure core technologies under the CTO organization and, once customer demand is confirmed, to transfer the glass substrate institutional sector to a business division and begin building production facilities.
An industry source said, "With rising demand for high-performance chips driven by the expansion of AI services, glass substrates are seen as 'a necessity, not a choice.'"