Patent ID: 6909143
Filing Date: 2005-06-21
Classification: H01L

Abstract:
1. A lateral double-diffused MOS (LDMOS) transistor comprising: a semiconductor substrate formed of a material having first conductivity type impurities; a drift region formed of a material having second conductivity type impurities on the semiconductor substrate; a first buried layer formed of a material having first conductivity type impurities and a second buried layer formed of a material having second conductivity type impurities, which are arranged at a boundary between the semiconductor substrate and the drift region; a first well region formed of a material having first conductivity type impurities to contact the first buried layer in a first portion of the drift region; a first source region formed of a material having second conductivity type impurities in a predetermined upper region of the first well region; a drain region formed of a material having second conductivity type impurities in a predetermined region of the drift region, the drain region being spaced a predetermined distance from the first well region; a third buried layer formed of a material having first conductivity type impurities in a second portion of the drift region, the third buried layer being overlapped with a part of an upper portion of the second buried layer; a second well region formed of a material having first conductivity type impurities in the second portion of the drift region, the second well region being overlapped with the third buried layer; a second source region formed of a material having second conductivity type impurities in a predetermined upper portion of the second well region; a gate insulating layer formed in a first channel region inside the first well region and in a second channel region inside the second well region; a gate electrode formed on the gate insulating layer; a source electrode formed to be electrically connected to the first source region and the second source region; and a drain electrode formed to be electrically connected to the drain region.