| abstract |
A semiconductor device that can alleviate electric field concentration at a corner of a trench bottom. A semiconductor substrate made of a wide band gap semiconductor, a first conductivity type drift layer formed on the semiconductor substrate, a second conductivity type base region formed on the drift layer, and the base region The first conductivity type source region formed on the upper portion of the first region, the first trench portion formed to penetrate the base region and the source region and reach the drift layer, and the drift layer immediately below the first trench portion A trench composed of a second trench portion narrower than the width of the trench portion, a gate insulating film formed on the side surface and the bottom surface in the trench along the first trench portion and the second trench portion, and gate insulation A gate electrode buried in the trench in which the film is formed, and a second conductivity type protective layer formed in the drift layer immediately below the first trench portion and the second trench portion of the trench. The example was a semiconductor device. [Selection] Figure 1 |