Patent ID: 9257594
Filing Date: 2016-02-09
CPC Classification: H01L

Claim Text:
1. A semiconductor device comprising a thin film transistor, the thin film transistor comprising: a gate electrode layer; a gate insulating layer over the gate electrode layer; a first source region and a first drain region over the gate insulating layer; a source electrode layer over the first source region; a drain electrode layer over the first drain region; a second source region over the source electrode layer; a second drain region over the drain electrode layer; and an oxide semiconductor layer over the gate insulating layer, the first source region, the first drain region, the source electrode layer, the drain electrode layer, the second source region, and the second drain region, wherein the oxide semiconductor layer has a higher oxygen concentration than oxygen concentrations of the first source region, the first drain region, the second source region, and the second drain region, wherein the oxide semiconductor layer is in contact with the gate insulating layer, the first source region, the first drain region, the second source region, and the second drain region, and wherein each of the oxide semiconductor layer, the first source region, the first drain region, the second source region, and the second drain region comprises at least indium, gallium, and zinc.