March 27, 2026 SUMCO CORPORATION
Announcement Regarding the Approval of Amendment to the "Plan for Ensuring Stable Supply" Based on the Economic Security Promotion ActSUMCO Corporation (hereinafter "the Company") announces that it has today received approval of
amendment to its "Plan for Ensuring Stable Supply" under the Economic Security Promotion Act, which was originally approved on July 14, 2023, from the Ministry of Economy, Trade and Industry (METI).
The revised plan shifts the focus from the initial plan for construction of a new plant for production
capacity expansion to the upgrading of manufacturing equipment at existing plants, thereby strengthening our ability to meet the evolving technical demands of leading-edge semiconductors. Accordingly, the
maximum subsidy amount has been updated from the initial 75.0 billion yen to 19.3 billion yen.
Notwithstanding this change, the core objective of the plan, which is to ensure a stable domestic supply of 300mm silicon wafers for leading-edge semiconductors, remains unchanged. The SUMCO Group remains committed to fulfilling its responsibility for the supply of silicon wafers.
The semiconductor market has recently undergone structural shifts; while demand for applications such as PCs and smartphones has stabilized, demand for generative AI is surging. In the leading-edge field of the 2nm generation and beyond, quality requirements are becoming increasingly stringent, and intense
technological competition is anticipated.
In light of these structural changes, the Company has determined that, at this stage, focusing management resources on upgrading manufacturing equipment to reliably capture rapidly growing demand for leading-edge products, rather than pursuing volume expansion, is the optimal course of action from the
perspectives of economic rationality and competitiveness.
Going forward, we will concentrate on upgrading our manufacturing equipment at existing plants,
including those in Imari City, Saga Prefecture, for the production of leading-edge products. Regarding
capacity expansion investments, including the construction of a new plant in Yoshinogari-cho, Kanzaki-gun, Saga Prefecture, the Company will continue to carefully assess market trends and make decisions at the appropriate time.
The SUMCO Group contributes to the development of a digital society and the realization of a net-zero society through the supply of high-quality silicon wafers. We remain committed to responding flexibly to changes in the market environment and balancing our contribution to the global semiconductor industry with Japan's economic security by ensuring the stable domestic production of silicon wafers that support social infrastructure.