Semiconductor device

A semiconductor device comprising:

• a semiconductor layer in which a gate trench having a side surface and a bottom surface and a source trench having a side surface and a bottom surface are formed;
• a first conductivity type source layer that is disposed so as to be exposed on a surface of the semiconductor layer and that defines the side surface of the gate trench and the side surface of the source trench;
• a second conductivity type channel layer that is disposed so as to be contiguous to the source layer on a back surface side of the semiconductor layer with respect to the source layer and that defines a part of the side surface of the gate trench and a part of the side surface of the source trench;
• a first conductivity type drain layer that is disposed so as to be contiguous to the channel layer on the back surface side of the semiconductor layer with respect to the channel layer and that defines the bottom surface of the gate trench and the bottom surface of the source trench;
• a gate electrode that is embedded in the gate trench;
• a gate insulating film disposed between the side and bottom surfaces of the gate trench and the gate electrode;
• a source electrode that is embedded in the source trench and that is electrically connected to the source layer;
• and
• a hetero junction diode formed at a joint surface between the source electrode and the drain layer.