Patent ID: 7170138
Filing Date: 2007-01-30
Classification: H01L

Abstract:
1. A semiconductor device comprising: a silicon island over a substrate having an insulating surface, the silicon island comprising a source region, a drain region, and a channel region located between the source region and the drain region; a gate electrode provided adjacent to the channel region with a gate insulating layer interposed therebetween; an impurity region having a lower concentration of an impurity than concentrations of the impurity in the source region and the drain region, the impurity region provided between the channel region and at least one of the source region and the drain region; and a layer comprising silicon nitride over the gate electrode and the silicon island, the layer having a portion in contact with the gate insulating layer, wherein the gate insulating layer has a first portion over the channel region and a second portion over the impurity region, at least a portion of the second portion is thinner than the first portion.