Patent ID: 9059281
Filing Date: 2015-06-16
Classification: H01L

Abstract:
1. A semiconductor device, comprising: a lateral diffused metal oxide semiconductor (LDMOS) comprising, in a first well with a first conductivity type, a trench isolation region, a first L-shaped drift region, and a second L-shaped drift region, wherein the first L-shaped drift region and the second L-shaped drift region are formed by additional doping of the first conductivity type; the trench isolation region surrounding a drain region and extending down in the first well in a substantially vertical direction; the first L-shaped drift region comprising a first section and a second section; the first section extending in a substantially lateral direction, a first end of the first section adjacent to the trench isolation region, a second end of the first section extending to a second well with a second conductivity type, the second well surrounding a body region and a source region; the second section extending down in the first well in the substantially vertical direction and being substantially parallel to the trench isolation region, an upper end of the second section connecting to the first end of the first section; the second L-shaped drift region comprising a third section and a fourth section; the third section extending in the substantially lateral direction and below a lower end of the trench isolation region, a first end of the third section connecting to a lower end of the second section; and the fourth section extending in the substantially vertical direction and surrounded by a lower section of the trench isolation region, a lower end of the fourth section connecting to a second end of the third section.