To provide a manufacturing method of semiconductor device which does not cause deterioration of the characteristic of an organic semiconductor material layer in the case of patterning the organic semiconductor material layer based on a lift-off method.

The manufacturing method of the semiconductor device forms a masking layer 32 having an inverse pattern on substrates 13 and 14 and thereafter, forms the organic semiconductor material layer 15A on the exposed substrates 13 and 14 and the mask layer 32. Next, after removing the mask layer 32 and the organic semiconductor material layer 15A on it, the method carries out baking treatment of the organic semiconductor material layer 15A to form a channel forming area consisting of the organic semiconductor material layer 15A.