Patent ID: 7800178

Claim:
A semiconductor device comprising: at least one thin film transistor including: a semiconductor layer that has a crystalline region including a channel region, a source region, and a drain region; a gate insulating film disposed at least on the channel region, the source region, and the drain region of the semiconductor layer; and a gate electrode arranged so as to oppose the channel region via the gate insulating film; wherein at least a portion of the semiconductor layer includes a catalyst element capable of promoting crystallization, and the semiconductor layer further includes a gettering region that includes the catalyst element at a higher concentration than in each of the channel region, the source region, and the drain region; a thickness of the gate insulating film on the gettering region is smaller than that on the source region and the drain region; and the gettering region, the source region, and the drain region include a same impurity element providing conductivity, the concentration of the same impurity element in the gettering region is higher than each of the concentrations of the same impurity element in the source region and the drain region.