SILICON CARBIDE SEMICONDUCTOR DEVICE, POWER CONVERTER, METHOD OF MANUFACTURING SILICON CARBIDE SEMICONDUCTOR DEVICE, AND METHOD OF MANUFACTURING POWER CONVERTER

摘要

A drift layer is formed of silicon carbide and has a first conductivity type. A trench bottom protective layer is provided on a bottom portion of a gate trench and has a second conductivity type. A depletion suppressing layer is provided between a side surface of the gate trench and the drift layer, extends from a lower portion of a body region up to a position deeper than the bottom portion of the gate trench, has the first conductivity type, and has an impurity concentration of the first conductivity type higher than that of the drift layer. The impurity concentration of the first conductivity type of the depletion suppressing layer is reduced as the distance from the side surface of the gate trench becomes larger.