POWER MOSFET, SEMICONDUCTOR DEVICE INCLUDING THE POWER MOSFET, AND METHOD FOR MAKING THE POWER MOSFET

摘要

metal oxide semiconductor field effect transistor according to the present invention includes a semiconductor substrate; Containing the first conductivity type impurity disposed on a semiconductor substrate, the well region to form by the addition of a second conductivity type impurity at a predetermined interval and a source region and a drain region separated from each other ; The source region and the insulating film disposed on a surface of the well region in the gap between the drain region; And a gate electrode disposed on the insulating film. The well region is made of epitaxial layer , the epitaxial layer comprises an impurity layer of the first conductivity type having different impurity concentrations .