Superjunction semiconductor device with columnar region under base layer and manufacturing method therefor

摘要

A semiconductor device that includes the following is manufactured: an n− base layer; a p-type base layer formed on the surface of the n− base layer; an n+ source layer formed in the inner area of the p-type base layer; a gate electrode formed so as to face a channel region across a gate insulating film; a plurality of p-type columnar regions that are formed in the n− base layer so as to continue from the p-type base layer and that are arranged at a first pitch; and a plurality of p+ collector layers that are selectively formed on the rear surface of the n− base layer and that are arranged at a second pitch larger than the first pitch.

主权项

1. A semiconductor device, comprising:
a first conductive type drain layer; a first conductive type drift layer formed on the first conductive type drain layer; a plurality of second conductive type base layers selectively formed on a surface of the first conductive type drift layer; a first conductive type source layer that is formed in an inner area of the respective second conductive type base layers at a gap from a periphery of the respective second conductive type base layers, the first conductive type source layer forming a channel region with said periphery; a gate electrode formed so as to face the channel region across a gate insulating film; a second conductive type columnar region that is formed in the first conductive type drift layer and that extends towards the first conductive type drain layer from at least some of the second conductive type base layers; a drain electrode electrically connected to the first conductive type drain layer; and a source electrode electrically connected to the first conductive type source layer, wherein the second conductive type columnar region has a top columnar region integrally formed with the respective second conductive type base layers and a bottom columnar region that is electrically floating.