Patent ID: 8859326

Claim:
A method of manufacturing a thin film transistor comprising: providing a substrate with a gate electrode and a gate insulating layer thereon, in that order proceeding from the substrate, the gate insulating layer having a planar surface facing away from the substrate; forming an organic semiconductor layer extending along only one plane of the gate insulating layer and not beyond the one plane of the gate insulating layer, the organic semiconductor layer having an island shape; forming a contact layer containing (a) an organic semiconductor material and an acceptor material or (b) an organic semiconductor material and a donor material on the organic semiconductor layer; patterning the organic semiconductor layer and the contact layer in the same form; forming a source electrode and drain electrode with end portions thereof on opposite ends of the contact layer; and removing the acceptor material or the donor material from the contact layer using the source and drain electrodes as a mask, wherein the step of forming the source and drain electrodes is performed between the step of patterning and the step of removing the acceptor material or donor material.