TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preparation (Claimed): 4,4-Dialkyl-2,6-trimethyl tin-cyclopentadiene-dithiophene of formula (II), 4,4-dialkyl-2,6-bromo-cyclopentadiene dithiophene of formula (III), and 5,8-di-(5-bromo-4-2-thienyl)-2,3-di-substituted-quinoxaline of formula (IV) are added to the organic solvent (A) containing catalyst (a) in oxygen-free environment, and Mille reaction is performed for 72 hours at 60-132 degrees C, to obtain thiophene-type organic semiconductor material (I).m=j+k.Preferred Process: 3,6-Dibromo-o-phenylenediamine is mixed with diethyl alkyl ketone, 5,8-dibromo-2,3-di-substituted-quinoxaline is prepared in the oxygen-free environment. 5,8-Dibromo-2,3-di-substituted-quinoxaline and 3-alkyl-2-thiophene boric acid are added to the organic solvent (B) containing catalytic agent (b) and reacted to preparing 5,8-di-(4-alkyl-2)-2,3-di-substituted-quinoxaline. N-Bromosuccinimide, 5,8-dibromo-2,3-di-substituted-quinoxaline and 3-di-substituted-quinoxaline are added into the mixed solvent containing sulfuric acid and trifluoroacetic acid to react at 10-30 degrees C for 12-48 hours, finally 5,8-di-(5-bromo-4-alkyl-2)-2,3-di-substituted-quinoxaline are prepared. 4,4-Dialkyl-cyclopentadiene dithiophene and butyl lithium are dropped at -78 degrees C to -25 degrees C to the organic solvent (C) to mix, then trimethyltin chloride is added to prepare 4,4-dialkyl-2,6-trimethyl tin-cyclopentadiene. Preferred Components: The catalyst (b) is organic palladium or organic palladium and organic phosphorus ligand. The organic solvent (B) is tetrahydrofuran, ether, dichloromethane, trichloromethane or ethyl acetate. The organic solvent (C) is tetrahydrofuran, ether, dichloromethane, trichloromethane or ethyl acetate. The organic solvent (A) is tetrahydrofuran, ethylene glycol dimethyl ether, benzene, chlorobenzene or toluene. The catalyst (a) is organic palladium or mixture of organic palladium and organic phosphorus ligand. The content of catalyst (a) is 0.05-50% with respect to total content of 4,4-dialkyl-2,6-cyclopentadiene-dithiophene. The organic palladium is tetrakis(triphenylphosphine)palladium, tris(dibenzylideneacetone)dipalladium or bis-triphenyl phosphine palladium chloride. The organic phosphorus ligand is tri(o-tolyl)phosphine.