Silicon carbide semiconductor device manufacturing method

摘要

In the manufacture of a silicon carbide semiconductor device having a termination region being a JTE region or FLR, the margin of the amount of etching for removing a damage layer formed in the surface of the termination region is enlarged. A silicon carbide semiconductor device has a termination region being a JTE (Junction Termination Extension) region or an FLR (Field Limiting Ring) at a termination of the semiconductor elements. The termination region is formed by one step of ion implantation in which the kind of impurity and the implant energy are fixed. In the impurity concentration profile of the termination region in the depth direction, the concentration peak in the shallowest position is in a position deeper than 0.35 μm from the surface, and the concentration in the surface portion is not more than one-tenth of the shallowest concentration peak.

主权项

1. A silicon carbide semiconductor device manufacturing method comprising steps of:
forming a given semiconductor element in a silicon carbide semiconductor layer; forming a termination region including at least one of a JTE (Junction Termination Extension) region and an FLR (Field Limiting Ring) by impurity ion implantation in a surface portion of said silicon carbide semiconductor layer in a periphery of said semiconductor element; performing activation annealing for said termination region; and after said activation annealing, removing a surface of said termination region by sacrificial oxidation, wherein said impurity ion implantation is performed at such an implant energy that an impurity concentration peak is in a position deeper than 0.35 μm from a surface of said silicon carbide semiconductor layer.