| 摘要 |
First, a titanium layer (39) is formed so as to cover an interlayer insulating film (37) on a MOS gate structure. Secondly, a nickel layer (40) that is in contact with a source region (33) is formed. Next, the whole of a silicon carbide wafer is exposed to a hydrogen plasma atmosphere that is formed by microwaves, so that the nickel layer (40) is caused to generate heat for heating by hydrogen radicals. At this time, the titanium layer (39) does not generate heat since reduction of an oxide film proceeds in the surface thereof. Consequently, only the source region (33) right below the nickel layer (40) is heated by heat transferred from the nickel layer (40). As a result, a silicide layer is formed at the interface between the silicon carbide wafer and the nickel layer (40), thereby forming an ohmic contact having a low contact resistance. Meanwhile, since the MOS gate structure is not heated, deterioration of the element characteristics can be prevented. In addition, a hydrogen plasma treatment is similarly applied when backside electrodes (41, 42) are formed. |
