Sumitomo Chemical

Sumitomo Chemical Co., Ltd. (Tokyo Stock Exchange: 4005) is a Japanese specialty chemical company and one of the world's key suppliers of photoresist materials used in advanced semiconductor lithography. Its EUV photoresist products are applied to silicon wafers during extreme ultraviolet lithography — the patterning process used to define transistors and interconnects at nodes of 7nm and below — where they determine the resolution, sensitivity, and line-edge roughness of the final pattern. The EUV photoresist market is highly concentrated. The dominant suppliers are all Japanese: JSR, Tokyo Ohka Kogyo (TOK), Shin-Etsu Chemical, Sumitomo Chemical, and Fujifilm collectively control approximately 90% of global photoresist supply. Japan's near-monopoly on photoresist has made it a focal point in export control discussions, as any restriction on photoresist exports to specific countries would directly constrain their ability to manufacture advanced chips. JSR's April 2024 acquisition by Japan Investment Corporation — a government-backed entity — signaled Japan's intention to treat photoresist as a strategic national asset. Sumitomo Chemical also manufactures compound semiconductors, including gallium arsenide and indium phosphide devices used in optical and RF applications, as well as specialty chemicals across the entire chipmaking flow including etchants, cleaning chemicals, and slurries used in chemical mechanical planarization. FY2023 revenue for the Sumitomo Chemical group was approximately ¥516 billion (~$3.4 billion). Its semiconductor materials division represents a small but strategically critical portion of this total, embedded in the supply chain of virtually every leading-edge AI chip in production.