SUMCO Corporation

In the semiconductor value chain, Japanese companies hold overwhelming global shares in materials, back-end processes, and electronic components. But former institutional investor Ryosuke Izumida points out that for equity investment, it is essential to analyze the degree of specialization and contribution—assessing how much a company’s semiconductor-related business contributes to its overall performance. Shin-Etsu Chemical leads the world in silicon wafers, with SUMCO in second place. Tokyo Ohka Kogyo is number one in photoresists. Ajinomoto Build-up Film holds about 95 percent of the global market for insulation film. Murata Manufacturing commands roughly 70 percent of MLCCs for AI servers. Japanese firms boast high technical capabilities. However, at highly diversified companies like Mitsui Chemicals and Mitsubishi Electric, expanding semiconductor demand may have only a limited impact on overall earnings and stock prices. In contrast, highly specialized firms such as SUMCO and Tokyo Ohka Kogyo tend to reflect the industry’s strength more directly. Izumida stresses the importance of bottom-up research—digging into earnings reports and briefing materials to gauge the contribution of semiconductor and AI-related businesses.