Patent ID: 9130037
Filing Date: 2015-09-08
Classification: H01L

Abstract:
1. A method of forming a semiconductor device, the method comprising: providing a semiconductor substrate including a first doping region, a second doping region, a third doping region, and a fourth doping region, wherein the second doping region is between the first doping region and the third doping region, and the third doping region is between the second doping region and the fourth doping region; forming a preliminary well region by injecting a first conductive type dopant into the first doping region and the third doping region; forming a well including a first well inner region, a second well inner region, and a well outer region by diffusing the first conductive type dopant, wherein the first well inner region is in the first doping region, the second well inner region is in the third doping region, and the well outer region surrounds the first well inner region and the second well inner region; forming a drift region by doping a second conductive type dopant into the second to fourth doping regions, wherein a lowest level of the drift region is above a lowest level of the well; and forming a body region by doping a first conductive type dopant into the first doping region, wherein the body region is in contact with a side of the drift region.