Lateral superjunction extended drain MOS transistor

摘要

An integrated circuit containing an extended drain MOS transistor with deep semiconductor (SC) RESURF trenches in the drift region, in which each deep SC RESURF trench has a semiconductor RESURF layer at a sidewall of the trench contacting the drift region. The semiconductor RESURF layer has an opposite conductivity type from the drift region. The deep SC RESURF trenches have depth:width ratios of at least 5:1, and do not extend through a bottom surface of the drift region. A process of forming an integrated circuit with deep SC RESURF trenches in the drift region by etching undersized trenches and counterdoping the sidewall region to form the semiconductor RESURF layer. A process of forming an integrated circuit with deep SC RESURF trenches in the drift region by etching trenches and growing an epitaxial layer on the sidewall region to form the semiconductor RESURF layer.

主权项

1. An integrated circuit, comprising:
an extended drain metal oxide semiconductor (MOS) transistor, including:
a drift region having a first conductivity type; anda plurality of deep semiconductor (SC) RESURF trenches in said drift region, in which:
each said deep SC RESURF trench includes a semiconductor RESURF layer contacting said drift region, said semiconductor RESURF layer having an opposite conductivity type from said drift region;said deep SC RESURF trenches are shallower than a bottom surface of said drift region, so that said deep SC RESURF trenches do not extend through said bottom surface of said drift region; andsaid deep SC RESURF trenches have a depth:width ratio of at least 5:1.