Abstract: A method of manufacturing a semiconductor device based on a SiC substrate involves forming an oxide layer on a Si-terminated face of the SiC substrate at an oxidation rate sufficiently high to achieve a near interface trap density below 5×1011 cm?2; and annealing the oxidized SiC substrate in a hydrogen-containing environment, to passivate deep traps formed in the oxide-forming step, thereby enabling manufacturing of a SiC-based MOSFET having improved inversion layer mobility and reduced threshold voltage. It has been found that the density of DTs increases while the density of NITs decreases when the Si-face of the SiC substrate is subject to rapid oxidation. The deep traps formed during the rapid oxidation can be passivated by hydrogen annealing, thus leading to a significantly decreased threshold voltage for a semiconductor device formed on the oxide.

Abstract: A method of manufacturing a semiconductor device based on a SiC substrate (12), comprising the steps of forming (201) an oxide layer (14) on a Si-terminated face of the SiC substrate (12) at an oxidation rate sufficiently high to achieve a near interface trap density below 5×1011 cm?2; and annealing (202) the oxidized SiC substrate in a hydrogen-containing environment, in order to passivate deep traps formed in the oxide-forming step, thereby enabling manufacturing of a SiC-based MOSFET (10) having improved inversion layer mobility and reduced threshold voltage. It has been found by the present inventors that the density of DTs increases while the density of NITs decreases when the Si-face of the SiC substrate is subject to rapid oxidation. According to the present invention, the deep traps formed during the rapid oxidation can be passivated by hydrogen annealing, thus leading to a significantly decreased threshold voltage for a semiconductor device formed on the oxide.