Silicon carbide semiconductor device and method of manufacturing silicon carbide semiconductor device

A silicon carbide semiconductor device comprising:

• a silicon carbide semiconductor structure;
• an insulated gate structure including
• a gate insulating film, which is a silicon dioxide film, contacting the silicon carbide semiconductor structure, and
• a gate electrode formed on the gate insulating film;
• an interlayer insulating film covering the insulated gate structure;
• a metal layer provided on the interlayer insulating film for absorbing or blocking hydrogen;
• and
• a main electrode provided on the metal layer and electrically connected to the silicon carbide semiconductor structure, wherein
• the metal layer is a first metal layer, and
• the silicon carbide semiconductor device further includes a second metal layer provided between the first metal layer and the main electrode, the second metal layer being a titanium nitride film and being chemically stable with respect to the first metal layer.

A method of manufacturing a silicon carbide semiconductor device, comprising:

• providing a silicon carbide semiconductor base having a silicon carbide semiconductor structure formed thereon;
• forming an insulated gate structure, including
• thermally oxidizing the silicon carbide semiconductor structure to form a silicon dioxide film on a surface thereof, and
• forming a gate electrode on the silicon dioxide film;
• forming an interlayer insulating film covering the insulated gate structure;
• forming a titanium film on the interlayer insulating film;
• forming an alloy film on the titanium film, the alloy film containing titanium and aluminum;
• and
• forming on the alloy film a main electrode that is electrically connected to the silicon carbide semiconductor structure.