TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Composition: The base is sodium carbonate. The molar amount of alkali aqueous solution of base is 2-20 times the content of compound (II).    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Composition: The organic palladium catalyst is tetrakis(triphenylphosphine)palladium. The molar ratio of organic palladium catalyst and compound (II) is 1:2000-1:5.    TECHNOLOGY FOCUS - POLYMERS - Preparation (claimed): Phenanthrene-type compound of formula (II) and carbazole-type compound of formula (III) are mixed in the molar ratio of 1:1.5-1.5:1 and subjected to Suzuki coupling reaction in presence of an organic solvent, an organic solution containing palladium catalyst and a base, under protective gas atmosphere. The resultant product is separated and purified to obtain 3,6-carbazole-benzodiazepin(benzothiadiazole)copolymer (I). Preferred Process: The reaction solution obtained after Suzuki coupling reaction, is added with mixture containing toluene and deionized water, and organic phase is extracted. The ethanol is added to extracted organic phase, filtered and obtained dried powder is dissolved in chloroform. The resultant mixture is subjected to silica gel column chromatography and organic solvent is removed. The obtained product is further subjected to methanol precipitation, filtered, washed with acetone, and precipitate is collected and filtered. The compound (I) is obtained by mixing 7,7'-dibromo-5,5'-diiodo-(4,4')bi(benzo(1,2,5)thiadiazolyl) and alkynyl-type compound of formula: R1-CC-R2 in the molar ratio of 1:2, carrying out ring closure reaction in presence of organic base, solvent and catalyst, separating and purifying. The organic base is triethylamine. The catalyst is palladium acetate. The compound (II) is obtained by mixing 2-ethoxy-3-(4,4,5,5-tetramethyl-(1,3,2)dioxaborolan-2-yl)-pyridine, carbazole-type compound of formula (IV) and N-butyl lithium in the molar ratio of 1:2 under protective gas atmosphere, adding tetrahydrofuran, stirring at room temperature for 6 hours, adding saturated sodium chloride aqueous solution, extracting with chloroform and filtering.