Mitsubishi Materials
A Tokyo-based diversified materials company that makes high-purity polysilicon for semiconductors at its Yokkaichi plant, along with electronic materials and copper products.
三菱マテリアル・Wafers, substrates and photomasks・Last updated: October 27, 2026
Overview
Mitsubishi Materials is headquartered in Chiyoda, Tokyo and works in non-ferrous metals, cement and electronic materials.
At its Yokkaichi plant in Mie Prefecture it produces high-purity polycrystalline silicon, the starting material that is melted and grown into single-crystal ingots for wafers.
Business: High-purity polysilicon and electronic materials
Why it matters
- Semiconductor-grade polysilicon must be far purer than solar-grade material, and only a few companies worldwide make it.
- Purification know-how from non-ferrous smelting underpins its polysilicon business.
Main products
- •High-purity polysilicon for semiconductors
- •Electronic materials
- •Copper products
Sites in Japan
Head officeHeadquarters
Chiyoda, Tokyo
Yokkaichi plantPlant
Yokkaichi, Mie