TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preparation (Claimed): A 9,9'-bifluorenylidene organic semiconductor material is prepared by oxidizing 2,7-dibromofluorene as raw material to obtain fluorene, reacting fluorene with acyl chloride and alkyl chain to obtain modified 2,7-alkyl chain fluorene, reacting with butyl lithium under strong alkali condition, dehydrating to obtain bilateral brominated 9,9'-fluorenylidene, reacting with double pinacolato diborane to obtain bilateral borate of 9,9'-fluorenylidene, performing coupling reaction of A, metal catalyst, and bilateral borate of 9,9'-fluorenylidene, adjusting structure, and introducing 9,9'-fluorenylidene into polymer or oligomer. Preferred Definitions:    M, R=O, alkenyl, alkynyl, aryl, carbonyl, OH, NH2, COOH, CN, NO2, and/or substituted functional ester in which substituent is H, F, Cl, Br, or I; and    A=compound of formula (III-1), compound of formula (III-2), compound of formula (III-3), compound of formula (III-4), compound of formula (III-5), compound of formula (III-6), compound of formula (III-7), compound of formula (III-8), compound of formula (III-9), compound of formula (III-10), compound of formula (III-11), compound of formula (III-12), compound of formula (III-13), compound of formula (III-14), compound of formula (III-15), compound of formula (III-16), compound of formula (III-17), compound of formula (III-18), compound of formula (III-19), compound of formula (III-20), compound of formula (III-21), compound of formula (III-22), compound of formula (III-23), compound of formula (III-24), compound of formula (III-25), compound of formula (III-26), compound of formula (III-27), compound of formula (III-28), compound of formula (III-29), compound of formula (III-30), compound of formula (III-31), compound of formula (III-32), compound of formula (III-33), compound of formula (III-34), compound of formula (III-35), compound of formula (III-36), compound of formula (III-37), compound of formula (III-38), compound of formula (III-39), compound of formula (III-40), and/or compound of formula (III-41).