Patent ID: 9634099
Date: 2017-04-25
CPC Classifications: H01L

Claim:
1. A lateral double diffused metal-oxide-semiconductor (LDMOS) device, comprising: a semiconductor substrate, having a first conductivity type; an epitaxial semiconductor layer formed over the semiconductor substrate, having the first conductivity type; a gate dielectric layer formed over the epitaxial semiconductor layer, having a step-like cross-sectional structure; a gate stack conformably disposed over the gate dielectric layer; a first doped region disposed in a portion of the epitaxial semiconductor layer adjacent to a first side of the gate stack, having the first conductivity type; a second doped region disposed in a portion of the epitaxial semiconductor layer adjacent to a second side of the gate stack opposite to the first side, having a second conductivity type opposite to the first conductivity type; a third doped region disposed in a portion of the first doped region, having the second conductivity type; a fourth doped region disposed in a portion of the second doped region, having the second conductivity type; an insulating layer covering the third doped region, the gate dielectric layer, and the gate stack; a conductive contact formed in a portion of the insulating layer, the third doped region, the first doped region, and the epitaxial semiconductor layer; and a fifth doped region disposed in a portion of the epitaxial semiconductor layer under the conductive contact, having the first conductivity type, wherein the fifth doped region physically contacts the semiconductor substrate and the conductive contact.