Samsung, SK Hynix Explore Laser Debonding Technology for HBM4

Samsung Electronics and SK Hynix are implementing a significant technological shift in high-bandwidth memory (HBM) wafer processing, according to Korean media outlet ETNews. This transition focuses on preventing wafer warping through the introduction of new laser-based debonding methods, a critical step for the next generation of HBM. The shift is expected to bring changes to the materials and equipment supply chains.

The two companies are collaborating with partners to replace the traditional mechanical wafer debonding process with laser methods. Wafer debonding involves separating the thinned wafer from a temporary carrier wafer, a process traditionally done using mechanical blades. However, as the number of HBM layers increases to 12 or 16, the wafers become thinner, and mechanical methods reach their limits.

When wafer thickness drops below 30 microns, there's a risk of damage, necessitating additional etching, polishing, and wiring steps, as well as new adhesives suitable for ultra-high temperatures. This need for robust adhesives that can't be separated mechanically drives the shift to laser debonding.

An industry expert explained, "To cope with the extreme processing environment, stronger adhesives are required, which mechanical methods can't handle. Hence, laser technology has been introduced to stably separate the primary and carrier wafers."

Samsung and SK Hynix are considering various laser techniques, including extreme ultraviolet (EUV) and ultraviolet (UV) lasers. Laser debonding is expected to be first applied to 16-layer HBM4. HBM4, which uses system semiconductor-based "base chips" at the bottom of the DRAM stack, requires finer processes and thinner wafers, making laser methods more suitable.

The introduction of laser debonding will inevitably impact the materials and equipment supply chains. Currently, mechanical debonding equipment is dominated by Tokyo Electron of Japan and SÜSS MicroTec of Germany. The shift to laser methods may invite more equipment manufacturers into the market, leading to intense competition.

Adhesives for wafer debonding are primarily supplied by companies such as 3M (USA), Shin-Etsu Chemical (Japan), Nissan Chemical, and TOK. These companies are reportedly developing new adhesive materials compatible with laser methods, replacing the existing mechanical approach.