Silicon carbide semiconductor device and method of manufacturing silicon carbide semiconductor device

Abstract

A semiconductor device having a semiconductor substrate that includes first to third epitaxial layers provided sequentially on a starting substrate, the third epitaxial layer forming a pn junction with the second epitaxial layer, and including a plurality of first semiconductor regions formed on a second semiconductor region. The semiconductor device further includes a plurality of trenches penetrating the first and second semiconductor regions to reach the second epitaxial layer, a plurality of gate electrodes provided in the trenches respectively via a gate insulating film, a metal film in ohmic contact with the first semiconductor regions, a first electrode electrically connected to the first semiconductor regions via the metal film, and a second electrode provided at a back surface of the starting substrate. Each of the starting substrate and the first to third epitaxial layers contains silicon carbide. The silicon carbide semiconductor device has a vacancy trap in an entire area of the semiconductor substrate.