METHOD FOR MANUFACTURING SILICON CARBIDE SEMICONDUCTOR DEVICE

摘要

In the present invention, a trench (TR) comprising an opening section (OP) and a corner section (CR) is formed in a silicon carbide substrate (100). A corner insulating film (201R) covering the corner section (CR) is formed. A gate insulating film (210) covering a region from the opening section (OP) to the corner section (CR) is formed. A step of forming the gate insulating film (201) comprises a step of thermally oxidizing the trench (TR), which is provided with the corner insulating film (210R). The step of thermally oxidizing the trench (TR) comprises a step of heating the silicon carbide substrate (100) to 1300°C or higher. This prevents the insulation breakdown of a gate oxidized film in a bottom section of the trench, and ensures the gate insulation film has adequately reliable insulation in in the vicinity of the opening section of the trench.