SILICON CARBIDE SEMICONDUCTOR DEVICE AND METHOD OF MANUFACTURE THEREOF

摘要

A silicon carbide semiconductor device and method of manufacture thereof is made by providing a channel control zone which has impurity concentration distribution increased gradually from a first doping boundary to reach a maximum value between the first doping boundary and a second doping boundary, then decreased gradually toward the second doping boundary, so that the silicon carbide semiconductor device is formed with a lower conduction resistance and increased drain current without sacrificing threshold voltage.

主权项

1. A silicon carbide semiconductor device, comprising:
a first semiconductor layer having a first conductivity; a second semiconductor layer located on the first semiconductor layer; an insulation layer located on the second semiconductor layer; a gate electrode located on the insulation layer; a first doping zone having a second conductivity opposite to the first conductivity and a first doping boundary and being located in the first semiconductor layer along the second semiconductor layer; a second doping zone having the first conductivity and a second doping boundary and being located in the first doping zone along the second semiconductor layer; and a third doping zone having the second conductivity and being located in the first semiconductor layer along the second semiconductor layer and abutting the second doping zone and partially overlapped with the first doping zone; wherein the first doping zone includes a channel control zone located along the second semiconductor layer between the first doping boundary and the second doping boundary; wherein the channel control zone has impurity concentration distribution increased gradually from the first doping boundary to reach a maximum value between the first doping boundary and the second doping boundary, then decreased gradually toward the second doping boundary;
wherein the impurity concentration of the second semiconductor layer forms a gradient distribution in a thickness direction thereof;wherein the gradient distribution has a peak value proximate the first semiconductor layer.