TECHNOLOGY FOCUS - POLYMERS - Preparation (Disclosed): Preparation of the polymer comprises reacting substituted tricyclic compounds of formula (I-x) with N-containing tricyclic compounds of formula (I-y) using palladium catalyst and a base under conditions to give the polymer of formula (I-z).X1x = Br; andX2x = SnR1x3; orX1x = Br; andX2x = B(OR1x)2; orX1x = SnR1x3; andX2x = Br; orX1x = B(OR1x)2; andX2x = Br; orX1x = H; andX2x = Br; andR1x = not defined.Preferred Components: The polymer (P1): additionally comprises at least one units comprising arylene or heteroarylene groups that have 5-30 ring atoms and are optionally substituted, preferably by at least one R1s which is fluoride, bromide, chloride, cyano, isocyano, cyanate, isocyanate, thiocyanate, isothiocyanate, substituted amide moiety of formula (C(O)R1mR2m), substituted carboxy moiety of formula (C(O)X1m) or (C(O)R1m), amine, substituted amine of formula (NR1mR2m), thiol, substituted thiol of formula (SR1m), hydrogen sulfite, substituted sulfone of formula (SO2R1m), hydroxy, nitro, trifluoromethyl, sulfur pentafluoride, optionally substituted silyl, carbyl or hydrocarbyl with 1-40C that is optionally substituted and optionally comprises at least one heteroatoms; is of formula (-(D1a)d-(A1a)a(Ar1a)b-(Ar2a)c)n-) (III); is of formula (Ia)-(Id); and of formula (R1t-chain-R2t). The mixture or polymer blend comprises the polymer (P1) and at least one n-type organic semiconductor compound. The n-type organic semiconductor compound is a optionally substituted fullerene. The monomer is of formula (R1r-Ar1a-D1a-Ar2a-A1a-R2r), (R1r-Ar1a-D1a-R2r), (R1r-Ar1a-A1a-R2r), (R1r-Ar1a-A1a-Ar2a-R2r), (R1r-A1a-R2r), (R1r-D1a-R2r), (R1r-Ar1a-R2r) or (R1r-Ar2a-R2r).R1m, R2m = H or optionally substituted 1-40C carbyl or hydrocarbyl;X1m = halo, preferably F, Br or Cl;a-d = 0-3, with at least one of a and d being different from 0 in at least one repeating unitn = greater than 1;x1, x2 = greater than 0 and less than or equal to 1;y, z = greater than or equal to 1 and less than 1;x1+x2+y+z = 1;chain = polymer chain comprising (III) or (Ia)-(Id);R1t, R2t = R1s, H, halo, -CH2Cl, -CHO, - CR1v=CR2v2, -SiR1vR2vR3v, -SiR1vX1vX2v, -SiR1vR2vX1v, -SnR1vR2vR3v, -BR1vR2v, -B(OR1v)(OR2v), -B(OH)2, -O-SO2-R1v, -CCH, -CC-SiR1v3, -ZnX1v or end-cap group; eitherR1v-R3v = R1m; andtwo of R1v-R3v = ring with the heteroatom to which they are attached; andX1v, X2v = halo. Preferred Definitions:    R3a, R4a = H; and    R1a, R2a and R5a-R8a = optionally branched alkyl, alkoxy or sulfanylalkyl with 1-30C or optionally branched alkylcarbonyl, alkylcarbonyloxy or alkyloxycarbonyl with 2-30C (all optionally substituted by at least one F); or    R1a-R2a = optionally branched alkyl, alkoxy or sulfanylalkyl with 1-30C or optionally branched alkylcarbonyl, alkylcarbonyloxy or alkyloxycarbonyl with 2-30C (all optionally substituted by at least one F), or aryl, heteroaryl, aryloxy or heteroaryloxy (all optionally fluorinated, alkylated or alkoxylated and has 4-30 ring atoms); and    R5a-R8a = aryl, heteroaryl, aryloxy or heteroaryloxy (all optionally fluorinated, alkylated or alkoxylated and has 4-30 ring atoms).    EXAMPLE - 108.1 mg 5,10-Dibromo-2,3,7,8-tetramethyl-pyrazino(2,3-g)quinoxaline, 203.2 mg 7,7-bis-(2-ethyl-hexyl)-2,5-bis-trimethylstannanyl-7H-3,4-dithia-7-sila-cyclopenta(a)pentalene, 13.3 mg tri-ortho-tolylphosphine and 10 mg tris(dibenzylideneacetone)dipalladium(0) were weighed into a flask and vacuum/nitrogen purged three times. 3.4 cm3 Degassed chlorobenzene was added and the mixture further purged with nitrogen for 15 minutes. The reaction mixture was heated to 140 degrees C for 3 hours 25 minutes with a preheated oil bath and stirring at 500 rpm. The reaction mixture was allowed to cool to 65 degrees C and the solution poured into 75 cm3 methanol with 3 x 10 cm3 methanol washings of the reaction flask. The polymer was collected by filtration and washed with 2 x 50 cm3 methanol to give a black solid. The polymer was washed via Soxhlet extraction with acetone, petrol (40-60), cyclohexane and chloroform. The chloroform fraction was precipitated into stirred 100 cm3 methanol. The polymer was collected by filtration, washed with 50 cm3 methanol and vacuum dried to yield 140 mg of poly(7,7-bis-(2-ethyl-hexyl)-3,4-dithia-7-sila-cyclopenta(a)pentalene)-alt-2,3,7,8-tetramethyl-pyrazino(2,3-g)quinoxaline (yield 79%).