TECHNOLOGY FOCUS - ELECTRONICS - Preferred transistor: The transistor further comprises: a gate electrode on a substrate; a source electrode and a drain electrode on the substrate, where the source electrode and the drain electrode facing each other and having a channel region; an insulation layer on the substrate, where the insulation layer electrically insulating the source electrode, the drain electrode, and the gate electrode; and an active layer in between the source electrode and the drain electrode, where the active layer including the organic semiconductor compound.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The compound (I) is preferably a compound of formula (Ia).    TECHNOLOGY FOCUS - POLYMERS - Preparation (disclosed): Preparation of (A1) involves reacting (I) (where R7 is X, and R8 is X') with aromatic compound of formula Y1-(Ar1)p-Y' and Z1-(Ar2)q-Z' in presence of palladium or nickel catalyst to give (V). No general method for the preparation of (I) is given.X, X', Y1, Y', Z1 and Z'=halo such as Br, I, Cl, trialkyltin or borane.Preferred Components: The organic semiconductor polymer is preferably a compound selected from 4 compounds of formulae as given in the specification e.g. a compound of formula (Va) or (Vb). The organic semiconductor polymer is a p-type organic semiconductor polymer.R1a and R1b=1-10C alkyl or 2-30C heteroaromatic ring group including at least one electron withdrawing imine nitrogen atom;orR1a or R1b=thiophenyl ring group or thiazolyl ring group fused with a pyrene moiety;R1c and R1d=1-20C alkyl;a-d=0-10;ora+b and c+d= less than or equal to 10;n=polymerization degree of a polymer.Provided that at least one of R1a and R1b is 2-30C heteroaromatic ring group including at least one electron withdrawing imine nitrogen atom; and one of R1a and R1b forms one of a thiophenyl ring group fused with a pyrene moiety and a thiazolyl ring group fused with a pyrene moiety. Preferred Definitions:    X1 and X4=N;    X2 and X3=S;    R1-R6=thiazolyl, thiadiazolyl, isoxazolyl, oxadiazolyl, imidazolyl, pyrazolyl, thiadiazolyl, trizolyl, tetrazolyl, pyridyl, pyridazinyl, quinolinyl, isoquinolinyl, quinoxalinyl, naphthyridinyl, benzoimidazolyl, pyrimidopyrimidinyl, benzothiadiazolyl, benzoselenadiazolyl, benzotriazolyl, benzothiazolyl, benzooxazolyl, phenanthrolinyl, phenazinyl, or phenantridinyl;    R7 and R8=thiophenyl, thiazolyl, thiadiazolyl, isoxazolyl, oxadiazolyl, imidazolyl, pyrazolyl, thiadiazolyl, trizolyl, tetrazolyl, pyridyl, pyridazinyl, quinolinyl, isoquinolinyl, quinoxalinyl, naphthyridinyl, benzoimidazolyl, pyrimidopyrimidinyl, benzothiadiazolyl, benzoselenadiazolyl, benzotriazolyl, benzothiazolyl, benzooxazolyl, phenanthrolinyl, phenazinyl or phenantridinyl;    Ar1 and Ar2=phenylene, thiophene, benzothiophene, thienothiophene, thiazole, thiazolothiazole, fluorene or carbazole.    SPECIFIC COMPOUNDS - 2 Compounds are disclosed as (I) e.g. 2,6-tert-butyl-4,8-di(2-thienyl)-pyreno(4,5-b:9,10-b')dithiazole (IA);    EXAMPLE - Cesium carbonate (Cs2CO3) (9.3 g) was added to a stirred solution of N,N'-(5,10-dibromo-2,7-di-tert-butylpyren-4,9-diyl)dithiophene-2-carbothioamide (7.2 g) in dimethyl formamide (DMF) (120 ml). The reaction mixture was heated at 120 degrees C for 3 hours. After the reaction was complete, it was cooled to room temperature and water was added. The precipitate was filtered and washed with dichloromethane (DCM) to give 2,6-tert-butyl-4,8-di(2-thienyl)-pyreno(4,5-b:9,10-b')dithiazole (4.5 g, yield: 80%) as yellow solid.