Patent ID: 6420758
Filing Date: 2002-07-16
Classification: H01L

Abstract:
A semiconductor device having a first semiconductor element and a second semiconductor element, said first semiconductor element comprising:a first semiconductor film formed over a substrate on an insulating surface; a first gate electrode adjacent to said first semiconductor film with a gate insulating film interposed therebetween; a second gate electrode covering said first gate electrode and being in contact with said gate electrode; a channel region formed in said first semiconductor film and overlapping with the region in contact with said gate insulating film of said first gate electrode, with said gate insulating film interposed therebetween; at least one impurity region formed in said first semicondutor and overlapping with the region in contact with said gate insulating film of said second gate electrode, with said gate insulating interposed therebetween; and a second semiconductor element comprising: a second semiconductor film formed over the substrate having the insulating surface; a third gate electrode adjacent to said second semiconductor film with said gate insulating film interposed therebetween; at least one impurity in said second semiconductor film not overlapping with said third gate electrode.