Patent ID: 8059222

Claim:
An active matrix substrate comprising an n-type thin film transistor, a p-type thin film transistor, and a photodiode, wherein the n-type thin film transistor includes a silicon film in which an n-type semiconductor region that will become a source region, an n-type semiconductor region that will become a drain region, and a p-type semiconductor region that will become a channel region are formed, the p-type thin film transistor includes a silicon film in which a p-type semiconductor region that will become a source region, a p-type semiconductor region that will become a drain region, and an n-type semiconductor region that will become a channel region are formed, the photodiode includes a silicon film in which a p-type semiconductor region, an intrinsic semiconductor region, and an n-type semiconductor region are formed, and the p-type semiconductor region and the n-type semiconductor region of the photodiode are arranged so that the intrinsic semiconductor region is interposed therebetween in a plane direction of the silicon film of the photodiode, and the intrinsic semiconductor region includes: a p-type semiconductor region at a position adjacent to the p-type semiconductor region of the photodiode, said p-type semiconductor region having a diffusion concentration of p-type impurities that is set at the same level as that of a diffusion concentration of p-type impurities in the channel region of the n-type thin film transistor; and an n-type semiconductor region at a position adjacent to the n-type semiconductor region of the photodiode, said n-type semiconductor region having a diffusion concentration of n-type impurities that is set at the same level as that of a diffusion concentration of n-type impurities in the channel region of the p-type thin film transistor.