At present, the most widely used silicon wafers can be mainly divided into polished and epitaxial wafers. Polished wafers are made of high-purity polysilicon and are used for DRAM, NAND Flash, etc., while epitaxial wafers are made by depositing a silicon single crystal layer with a thickness of several micrometers (µm) onto polished wafers, which are mainly used in systems semiconductor. It is reported that the wafers developed and mass-produced by SK Siltron are mainly used for the latest 10nm-class DRAM.
Samsung and SK Hynix have introduced the extreme ultraviolet (EUV) process in the fourth generation (1a) DRAM. EUV is a new generation of exposure technology using equipment exclusively produced by ASML in the Netherlands. Since EUV has different characteristics from existing light wavelengths, different materials must be used, and the development of 1a DRAM wafers is also very difficult.
It is understood that before SK Siltron joined the supply, only Japan’s Shengco and Shin-Etsu Chemical could supply. Samsung and SK Hynix, which will mass-produce 1a DRAM in the second half of 2021, previously only used wafers produced in Japan.
Relevant persons said that under the circumstance that the proportion of 1a DRAM continues to increase, the successful R&D and mass production of SK Siltron will undoubtedly help South Korea realize the diversification of the material supply chain, which is of special significance from the perspective of South Korea’s localization industry. SK Hynix plans to increase the proportion of 1a DRAM to about 1/4 of production by the end of 2022.
On the other hand, in 2021, SK Siltron’s market share of 12-inch wafers will be about 18%, ranking third in the industry, while Shengko’s market will account for 30% and Shin-Etsu Chemical’s market will account for 25%. close the gap.