Patent ID: 8835935

Claim:
A trench metal oxide semiconductor (MOS) transistor device, comprising: a substrate of a first conductivity type, having a first surface and a second surface; a drift region of the first conductivity type, disposed on the first surface of the substrate and having at least one trench therein; a trench doped region of a second conductivity type, disposed in the trench; an epitaxial region of the second conductivity type, disposed on the drift region and the trench doped region; a trench gate, passing through the epitaxial region, wherein a distance between a bottom of the trench gate and a bottom of the trench doped region is 0.5˜3 μm; a gate insulating layer, disposed on a surface of the trench gate; a source region, disposed in the epitaxial region and disposed beside two sides of the trench gate; a drain electrode, disposed on the second surface of the substrate; a source electrode, disposed on the source region; a side spacer, disposed on two sides of the trench doped region; and a doped region of the second conductivity type, disposed at a bottom of the trench doped region, wherein the doped region is in contact with the drift region and the trench doped region.