An N-channel TFT and OLED display apparatus and electronic device using the same are disclosed. The N-channel TFT comprises a a substrate; an active layer on the substrate, wherein the active layer comprises an N type source region and an N type drain region; a gate dielectric layer on the active layer; and a gate region on the gate dielectric layer. At least a part of the highly-doped source region is located under the gate region, and at least a part of the lightly-doped drain region is located under the gate region.
