Patent ID: 7956354

Claim:
A flat display device having the organic thin film transistor formed by the following method: forming source and drain electrodes on a substrate; forming an organic semiconductor layer on the source and drain electrodes and the substrate; selectively printing a mask material on a portion of the organic semiconductor layer; patterning the organic semiconductor layer by a dry etching method using the mask material; forming a gate insulating film on the substrate; and forming a gate electrode on the gate insulating film; wherein the flat display device comprises a plurality of pixels arranged in a matrix shape having rows and columns, each of the pixels having at least one organic thin film transistor, wherein the organic thin film transistor comprises one or more gate electrodes, one or more source electrodes and one or more drain electrodes, and a semiconductor layer, and the semiconductor layer has a box shape, a line shape extended in a row or column direction, or a mesh shape extended in row and column directions corresponding to at least the source and drain electrodes and a portion between the source and drain electrodes.