DMOS transistor with a slanted super junction drift structure

摘要

A DMOS transistor with a lower on-state drain-to-source resistance and a higher breakdown voltage utilizes a slanted super junction drift structure that lies along the side wall of an opening with the drain region at the bottom of the opening and the source region near the top of the opening.

主权项

1. A DMOS transistor comprising:
a semiconductor structure having:
a top surface of a semiconductor substrate;a rectangular shaped opening that extends from the top surface into the semiconductor structure, the opening having a bottom surface and a side wall surface, wherein the side wall surface is slanted;a drain region of a first conductivity type that touches the bottom surface of the opening;a body region of a second conductivity type that touches the top surface;a drift structure that touches the side wall surface of the opening, the drift structure having a first region of the first conductivity type and a second region of the second conductivity type, the first region directly touching the drain region and having a first region surface that lies substantially in parallel with the side wall surface of the opening, the second region separated from the drain region by a portion of the semiconductor substrate, the second region touching the body region and having a second region surface that touches the first region surface;a source region of the first conductivity type that touches the body region;a channel region in the top surface of the body region that lies horizontally between and touches the drift structure and the source region;a non-conductive region that fills the rectangular shaped opening; anda metal drain contact that extends through the non-conductive region to the top surface, contacting and connecting to the drain region.