SK hynix is accelerating the development of a new process, “Hybrid Bonding,” to maintain its global leadership in High Bandwidth Memory (HBM). The industry is closely watching whether SK hynix can continue to lead the specialty memory sector by being the first to apply this dream packaging technology.

According to industry officials on Dec. 18, SK hynix announced at the IEDM 2023, a global semiconductor conference held in the U.S. this month, that it has secured reliability for the Hybrid Bonding process used in HBM manufacturing. SK hynix reported that its third-generation HBM (HBM2E), which stacks DRAM in 8 layers, passed all areas of a reliability test after being manufactured using the Hybrid Bonding process. In this test, SK hynix evaluated the HBM’s lifespan when left at high temperatures and examined potential issues that could arise during the chip bonding process by customers after product shipment, among other things, across four categories.

Hybrid Bonding is considered a “dream process technology” in the HBM industry. Until now, HBM was connected using a material called “micro bumps” between DRAM modules. However, with Hybrid Bonding, chips can be connected without bumps, significantly reducing the thickness of the chips by eliminating the bumps that act as bridges.

The standard thickness for HBM chips has been 720 μm. The 6th generation HBM (HBM4), expected to be mass-produced around 2026, requires stacking 16 DRAM vertically, which is challenging with current packaging technologies to meet customer satisfaction. Therefore, the application of the Hybrid Bonding process in next-generation HBM is deemed inevitable in the industry.

SK hynix has already announced plans to apply Hybrid Bonding to its HBM4 products this year. Although this test was conducted on a third-generation product, which is far less demanding than the HBM4 specifications and only half the number of DRAM layers (8 layers), it is significant in demonstrating the potential of Hybrid Bonding externally.

SK hynix has been a key player in the HBM boom in the semiconductor industry this year. The company has maintained its position as the leader in the HBM industry by being the first to introduce a process called Mass Reflow-Molded Underfill (MR-MUF) in the production of the 5th generation HBM this year.