Patent ID: 7973361
Filing Date: 2011-07-05
Classification: H01L

Abstract:
1. A high breakdown voltage semiconductor device formed using an SOI substrate comprising a support substrate, an insulating film formed on the support substrate, and a second conductive type active layer formed on the insulating film, the device comprising: a first conductive type well region formed in an upper side of the second conductive type active layer; a second conductive type drain offset region formed in the upper side of the second conductive type active layer and apart from the well region; a second conductive type source region formed in an upper side of the well region; a second conductive type drain region formed in an upper side of the drain offset region; a gate insulating film formed in at least a region interposed between the source region and the drain offset region in the active layer; and a gate electrode formed on the gate insulating film, wherein the device further comprises a first conductive type deep well region formed under the drain offset region of the active layer, and a lower surface of the deep well region is in contact with the insulating film, a second conductive type impurity introduced for formation of the drain offset region has a concentration profile in which a concentration peak is located in the vicinity of a surface of the active layer, and a first conductive type impurity introduced for formation of the deep well region has a concentration profile in which a concentration peak is located deeper than the concentration peak of the second conductive type impurity and the first conductive type impurity concentration decreases toward the surface of the active layer.