Patent ID: 7863081

Claim:
A method of forming an organic semiconductor layer for a field effect transistor, the organic semiconductor layer comprising a porphyrin copper complex compound, the method comprising the steps of: applying a solution containing a bicycloporphyrin copper complex compound to a substrate; and heating the substrate applied with the solution containing the bicycloporphyrin copper complex compound at a temperature of between 200Â° C. and 220Â° C. to form the organic semiconductor layer, wherein the bicycloporphyrin copper complex compound is a complex obtained by coordinating a copper atom with metal-free bicycloporphyrin, and the metal-free bicycloporphyrin is recrystallized and wherein the organic semiconductor layer contains crystal grains having a maximum diameter of at least 10 Î¼m, the crystal grains accounting for at least 25% of a surface area of the organic semiconductor layer.