Patent ID: 6323525
Filing Date: 2001-11-27
Classification: H01L

Abstract:
A semiconductor device having a MISFET, said MISFET comprising:a first semiconductor layer of a first conductivity type for forming a channel region;a gate electrode facing the channel region via a gate insulating film;a second semiconductor layer of a second conductivity type formed in each of source and drain regions so as to be in contact with said first semiconductor layer;a third semiconductor layer formed on said second semiconductor layer in the drain region, said second semiconductor layer being sandwiched between said first and third semiconductor layers; andfirst and second main electrodes respectively connected to the source and drain regions,wherein an upper edge of said third semiconductor layer is formed above a boundary between said first semiconductor layer and said gate insulating film,a value obtained by subtracting a concentration of a first conductivity type impurity from a concentration of a second conductivity type impurity in said second semiconductor layer is set larger than a value obtained by subtracting a concentration of the first conductivity type impurity from a concentration of the second conductivity type impurity in said third semiconductor layer,a value obtained by subtracting the concentration of the first conductivity type impurity from the concentration of the second conductivity type impurity in said third semiconductor layer is smaller than a value obtained by subtracting a concentration of the second conductivity type impurity from a concentration of the first conductivity type impurity in said first semiconductor layer, anda sidewall insulating film is interposed between said drain region and said gate electrode, and has an outer side surface inclined upward from said gate insulating film to said third semiconductor layer, such that said outer side surface is separated from said gate electrode more on an upper side than on a lower side, and said second and third semiconductor layers each have an end disposed on said outer side surface.