SILICON CARBIDE SEMICONDUCTOR DEVICE MANUFACTURING METHOD

摘要

Provided is a method for manufacturing a silicon carbide semiconductor device which includes the steps in the following order: a first step of forming a thermal oxide film on one surface of an SiC substrate by thermal oxidation at a temperature of 1150°C or above in a gas atmosphere including molecules which contain nitrogen and oxygen, and introducing highly-concentrated nitrogen to one surface of the SiC substrate in the course of forming the thermal oxide film; a second step of forming a highly-concentrated n-type SiC layer on one surface of the SiC substrate such that the thermal oxide film is removed from one surface of the SiC substrate by etching and, thereafter, one surface of the SiC substrate is exposed to radicals so that Si-N bonded bodies and C-N bonded bodies which are formed on one surface of the SiC substrate are removed while leaving nitrogen introduced into a lattice of SiC out of highly-concentrated nitrogen introduced into one surface of the SiC substrate; and a third step of forming an ohmic electrode layer on one surface of the SiC substrate. An ohmic electrode layer can be formed on an SiC layer without performing a high-temperature annealing step.