Patent ID: 6781201
Filing Date: 2004-08-24
Classification: H01L

Abstract:
A semiconductor device comprising:a semiconductor substrate of a first conductivity type and having a main surface with a first area where a power MOSFET is provided and a second area where a peripheral device is provided; first and second semiconductor regions of the first conductivity type, respectively provided in the semiconductor substrate at the first area and the second area and having impurity concentrations approximately equal to each other and lower than that of the semiconductor substrate; first and second trenches respectively extending in the first and second semiconductor regions and having depths approximately equal to each other; first and second insulating films respectively provided on inner walls of the first and second trenches; and first and second conductive members respectively filling the first and second trenches with the first and second insulating films interposed therebetween, wherein: the power MOSFET is composed of the first semiconductor region as a drift region, a base region of a second conductivity type extending in the drift region, a source region of the first conductivity type extending in the base region, the first insulating film as a gate insulating film, and the first conductive member as a gate electrode that extends to face the drift region, the base region, and the source region via the gate insulating layer, and the peripheral device is a MOSFET composed of the second semiconductor region as a well layer, the second insulating film as a gate insulating film, the second conductive member as a gate electrode, source and drain regions provided in the well layer separately from each other, the source and drain regions facing the gate electrode with the gate electrode interposed therebetween.