HIGH VOLTAGE FIELD BALANCE METAL OXIDE FIELD EFFECT TRANSISTOR (FBM)

摘要

A semiconductor device includes a semiconductor substrate of a first conductivity type. A first conductivity type epitaxial layer disposed on a top surface of the substrate includes a surface shielded region above a less heavily doped voltage blocking region. A body region of a second conductivity type opposite the first conductivity type is disposed near a top surface of the surface shielded region. A first conductivity type source region is disposed near the top surface inside the body region. A drain is disposed at a bottom surface of the substrate. A gate overlaps portions of the source and body regions. Gate insulation separates the gate from the source and body regions. First and second trenches formed in the surface shielded region are lined with trench insulation material and filled with electrically conductive trench filling material. Second conductivity type buried doped regions are positioned below the first and second trenches, respectively.

主权项

1. A semiconductor device, comprising:
a semiconductor substrate of a first conductivity type; an epitaxial layer of the first conductivity type disposed on a top surface of the semiconductor substrate, wherein the epitaxial layer includes a surface shielded region positioned above a voltage blocking region, the surface shielded region is more heavily doped than the voltage blocking region; a body region of a second conductivity type that is opposite of the first conductivity type disposed near a top surface of the surface shielded region, a source region of the first conductivity type disposed near the top surface of the surface shielded region inside the body region, and a drain disposed at a bottom surface of the semiconductor substrate, a gate overlapping a portion of the source region and a portion of the body region having a gate insulation layer separating the gate from the source region and the body region; first and second trenches formed in the surface shielded region, wherein the first and second trenches are lined with a trench insulation material and filled with an electrically conductive trench filling material; a first buried doped region of the second conductivity type positioned below the first trench, a second buried doped region of the second conductivity type positioned below the second trench, and wherein the first and second buried doped regions extend to a depth substantially the same as a depth of a bottom surface of the surface shielded region.