As competition in high bandwidth memory (HBM) to boost artificial intelligence (AI) semiconductor performance intensifies, the core task has shifted from how small to make memory to how precisely to stack and consolidation it. Because HBM vertically stacks multiple DRAM chips, resistance, heat generation, and signal loss in the chip-to-chip consolidation (interconnect) determine overall performance. As the number of stacks grows and gaps narrow to the nanometer level, the limits of conventional methods have emerged, and hybrid bonding to replace them is rising as a next-generation technology.
On the 12th, the Institute of Industrial Education held a "Commercialization strategy seminar for HBM response: AI Semiconductor and hybrid bonding technology innovation and leap forward," introducing hybrid bonding technology, glass substrates and interposers, packaging structure changes after HBM4, and response strategies for domestic corporations. Academia and the equipment, materials, and investment industries took part in the seminar to focus on technical and industrial issues during the packaging transition.
Conventional HBM has stacked chips using solder bumps, but as the stacked structure becomes more complex, signal loss and heat issues worsen, revealing an inherent limit in achieving fine alignment. In response, the industry is moving toward adopting hybrid bonding, which directly bonds metal surfaces without bumps, as a next-generation packaging technology. Yoon Chang-min, a professor in the Department of Polymer Science and Engineering at Inha University, said, "Hybrid bonding is a high-difficulty process that simultaneously bonds copper (Cu) and the insulating film (SiO₂), and performance is secured only when the surfaces are planarized to the atomic level and precisely aligned," and noted, "Cleaning, surface treatment, temperature, and pressure conditions all have to line up."
Across the industry, a packaging-centered competitive landscape is also becoming clear. Noh Geun-chang, head of research at Hyundai Motor Securities, said, "The HBM race is moving to a structure where the outcome is decided in packaging rather than in fine processing," and assessed, "Instead of the size of facilities, understanding of processes and the accumulation of trial and error are what separate corporations in competitiveness." In other words, packaging is being redefined not as simple assembly but as a strategic technology for the AI Semiconductor era.
Corporations on the ground share the same view. Kim Sung-jin, CEO of Ajin Electronics, said, "Advanced packaging is not about how many pieces of equipment you have; the key is how you design the process and which combinations of materials you use to solve problems." In particular, glass interposers and low-temperature hybrid bonding, which are drawing attention in next-generation HBM, are cited as areas where Korean corporations can show strengths. He said, "Korea has built up glass substrate technology and infrastructure through the display industry, and its ecosystem that can coordinate substrates, materials, and equipment together is a strength."
Equipment companies also say shifts in customer demands have become clear. Lee Seok-jun, CEO of ITI, said, "HBM packaging is a high-difficulty process that must manage alignment error and bonding reliability at the same time," and explained, "Recently, global clients are finding that equipment specs alone do not yield the quality they want, so they are looking for partners who can co-design and validate the entire process." Based on precision cutting technology for glass substrates and silicon wafers, ITI is assessed to have competitiveness in substrate and wafer processing for HBM stacking. He added, "Glass and silicon have completely different thermal and mechanical properties. There are not many companies globally that can cut both materials without cracks."
However, the domestic packaging industry structure still faces challenges. While Taiwan's ASE and SPIL continue large-scale investments based on high profitability, domestic packaging companies have low profit margins and lack the capacity for long-term R&D investment. Noh said, "Packaging in the HBM era is a strategic technology that determines semiconductor performance, not a simple outsourced process," and added, "Domestic corporations also need to secure the capacity for mid- to long-term investment."
The industry assesses that the center of gravity in the HBM race has already shifted from "fine processing" to "precision packaging." It is an era in which corporations are ranked by who presents a more complete solution in bonding precision, material combinations, and substrate and wafer processing. There is also analysis that domestic corporations, which have accumulated packaging process capabilities, are meeting new opportunities at the threshold of a technological transition. The more complex the stacking and bonding structures of HBM become, the more Korea's process engineering capabilities by corporations are expected to emerge as a meaningful variable in the global competitive landscape.