Japan Controls 100% of EUV Photoresist Supply and Is Weaponizing It as a Geopolitical Tool

Tokyo Ohka Kogyo (TOK) and JSR together control approximately 91% of the global photoresist market, and for EUV photoresists used in sub-7nm chips, Japan provides 100% of the world's supply. In November 2025, Japan's Ministry of Economy, Trade and Industry (METI) placed 12 core semiconductor materials including high-end ArF/EUV photoresists on its export control list, restricting supply to 42 Chinese companies, demonstrating that this monopoly can be and is being weaponized. Why it matters: Every advanced chip below 7nm (including all AI accelerators, leading-edge mobile processors, and HPC chips) requires EUV photoresist from Japanese suppliers, so any disruption to Japan's photoresist supply immediately halts production at TSMC, Samsung, and Intel foundries worldwide, so the entire advanced semiconductor supply chain has a single-country dependency that is not addressed by any CHIPS Act or EU Chips Act diversification effort, so chipmakers like TSMC and Samsung have zero negotiating leverage on pricing or supply priority for this critical input, so the global semiconductor industry's $700+ billion annual revenue depends on a handful of chemical plants in Japan that could be disrupted by natural disaster (Japan sits on the Pacific Ring of Fire), trade disputes, or policy shifts. The structural root cause is that EUV photoresist requires extraordinarily precise chemical formulations at the molecular level, Japan holds 70% of related patents globally, and the development cycle for qualifying a new photoresist chemistry takes 5-7 years of co-development with lithography tool makers and foundries. No country or company outside Japan has successfully replicated production-grade EUV photoresist, and the capital investment plus IP barriers make new entry nearly impossible within this decade.