Semiconductor device, method for manufacturing semiconductor device, inverter circuit, driving device, vehicle, and elevator

A semiconductor device, comprising:

• a silicon carbide layer;
• a gate electrode;
• a gate insulating layer disposed between the silicon carbide layer and the gate electrode;
• and
• a gate insulating layer disposed between the silicon carbide layer and the gate electrode;
• and
• a region disposed in the silicon carbide layer and containing nitrogen (N), the region disposed adjacent to the gate insulating layer, a full width at half maximum of a concentration distribution of nitrogen in the region being 1.5 nm or more and 5 nm or less.

A semiconductor device, comprising:

• a silicon carbide layer;
• a gate electrode;
• a gate insulating layer disposed between the silicon carbide layer and the gate electrode;
• and
• a region disposed in the silicon carbide layer and containing nitrogen (N), the region disposed adjacent to the gate insulating layer, the region having a first nitrogen atom bonded to two silicon atoms and a second nitrogen atom bonded to the first nitrogen atom and also bonded to two silicon atoms.

A method for manufacturing a semiconductor device, comprising:

• forming a first region including nitrogen by performing heat treatment on a silicon carbide layer having an exposed surface at a temperature of 1300° C. or more and 1400° C. or less in an N2 gas having an oxygen partial pressure of 0.1 ppm or less;
• forming a gate insulating layer on the silicon carbide layer after the forming the first region;
• and
• forming a gate electrode on the gate insulating layer.