MANUFACTURING METHOD OF SILICON CARBIDE SEMICONDUCTOR DEVICE

摘要

In producing a MOS silicon carbide semiconductor device, after a first heat treatment (oxynitride) is performed in an oxidation atmosphere including nitrous oxide or nitric oxide, a second heat treatment including hydrogen is performed, whereby in the front surface of a SiC epitaxial substrate, a gate insulating film is formed. A gate electrode is formed and after an interlayer insulating film is formed, a third heat treatment is performed to bake the interlayer insulating film. After contact metal formation, a fourth heat treatment is performed to form a reactive layer of contact metal and the silicon carbide semiconductor. The third and fourth heat treatments are performed in an inert gas atmosphere of nitrogen, helium, argon, etc., and a manufacturing method of a silicon carbide semiconductor device is provided achieving a normally OFF characteristic and lowered interface state density.

主权项

1. A manufacturing method of a silicon carbide semiconductor device, the manufacturing method comprising:
forming a gate insulating film on a surface of a semiconductor substrate of silicon carbide, the surface being tilted within a range of 0 degrees or greater and 8 degrees or less from any one among a (000-1) surface and a (11-20) surface, the gate insulating film being formed by performing on the semiconductor substrate, a second heat treatment in an atmosphere that includes hydrogen, after a first heat treatment is performed in an oxidation atmosphere obtained from an oxidized compound that includes nitrogen; and performing in an inert gas atmosphere, a third heat treatment that is performed after the forming of the gate insulating film, wherein the third heat treatment is performed in any one among a first process for forming an electrical contact unit of the semiconductor substrate and a contact metal that abuts the semiconductor substrate, a second process for lowering resistivity of a gate electrode formed on the gate insulating film, and a third process for baking an interlayer insulating film that electrically insulates the metal film and the gate electrode.