TECHNOLOGY FOCUS - ELECTRONICS - Preferred Components: The semiconductor device contains (I) and/or an oligomer or polymer, as a layer having a thickness of 5-1000 nm, on a rigid or flexible solid substrate.    TECHNOLOGY FOCUS - POLYMERS - Preparation (Disclosed): Preparation of (I) comprises reaction of a halo substituted thiophene compound of formula (1a) with a lithiating agent to give a thienyl-lithium compound of formula (2a); and reaction of (2a) with a reagent of formula (Y2a-X-Z) to give a thiophene compound of formula (Ib) (representative of (I)).Hal = halo, especially Br; andY2a, Z = moieties able to form a covalent bond with thienyl-lithium. Full Definitions:    R1, R1a = H or a substituent, halo or SiR6R4R5;    R2, R2a = 1-25C alkyl, 3-12C cycloalkyl, 2-25C alkenyl, 2-25C alkynyl, 4-25C aryl, 5-25C alkylaryl or 5-25C aralkyl (all optionally substituted);    X = divalent linking group comprising -C(R3)=C(R3a)-, -C(=N-R23)-C(=N-R23a)- (a) or -C(=O)-N(R8)-C(=O)-; either    R3, R3a = H or a substituent, or amino, if R3 and R3a together complete a ring structure, or X is a bridging group which is (a) or a group of formula (b), R2 and/or R2a may also be halo or H;    CR3R3a = 5- or 6-membered optionally substituted hydrocarbon ring, or a 5-membered optionally substituted heterocyclic ring comprising at least one heteroatom comprising N, O, S, where one substituent on the heterocyclic ring is a fused thiophene moiety of formula (IV); or    R3R3a = bridging group (b);    Y1, Y1a = phenyl (substituted by R7 and R7a), a thiophene moiety of formula (c), -C(R7)=C(R7a)- or -C?=C-;    n, p = 0-6;    L = a divalent organic linking group, such as alkylene (e.g. 2-12C), phenylene or cycloalkylene;    A1 = divalent moiety of O, S or NR; either    R4-R6 = 1-25C alkyl, 3-12C cycloalkyl, 4-25C aryl or 5-25C aralkyl; or    R4R5 = divalent hydrocarbon residue of 4-25C (optionally substituted and/or interrupted); either    R7, R7a = H or substituent; or    vicinal CR7R7a = 5-membered optionally substituted heterocyclic ring comprising at least one heteroatom of N, O or S;    R8 = substituted 4-10C aryl or 1-19C heteroaryl, where aryl or heteroaryl are attached via divalent organic linking group L; either    R9, R9a, R10, R10a = H; or    CR9R9a, CR9R10, CR9aR10a = 5-membered optionally substituted heterocyclic ring comprising at least one heteroatom of N, O or S;    R23, R23a = a substituent, especially alkyl, OH or alkoxy, where any substituent, if present, is halo, OR, 1-25C alkyl, 2-25C alkenyl, 1-25C alkylthio, 1-25C acyl, 4-10C aryl, 1-9C heteroaryl, 3-12C cycloalkyl, 2-11C heterocycloalkyl, 1-25C acyloxy, or is residues COR, CH=NR, CH=N-OH, CH=N-OR, COOR, CONHR, CONRR1a, CONH-NHR, CONH-NRR1a, SO2R, SO3R, SO2NHR, SO2NRR1a, SO2NH-NHR, SO2NH-NRR1a, S(O)R, S(O)OR, S(O)NHR, S(O)NRR1a, S(O)NH-NHR, S(O)NHNRR1a, SiRR1aR2a, PORR1a, PO(OR)R1a, PO(OR)2, PO(NHR)2, PO(NRR1a)2, CN, NO2, NHR, NRR1a, NH-NHR, NH-NRR1a or CONROH, if bonding to saturated C or to S, may also be oxo; and    R, R1a, R2a = H, 1-25C alkyl, 1-25C haloalkyl, 5-10C aryl, 3-12C cycloalkyl, preferably 1-6C alkyl, phenyl, cyclopentyl or cyclohexyl, where each substituent, or R, R1a and R2a which is 4-10C aryl or 1-9C heteroaryl, itself is optionally substituted by 1-4C alkyl, 2-4C alkenyl, 1-4C alkoxy, CHO, 1-4C alkyl-carbonyl, 2-4C alkenyl-carbonyloxy, allyloxy, halo, and any neighboring substituents may be linked together by a carbon-carbon single bond or double bond.    Preferred Definitions:    R, R1a, R2a = 1-18C alkyl, phenyl, cyclopentyl, cyclohexyl; and    R8 = substituted phenyl or substituted heteroaryl comprising thienyl or dithienyl.    EXAMPLE - 3,3'-Dibromo-4,4'-dihexyl-5,5'-bis-trimethylsilanyl-(2,2')bithiophenyl (10 g) was lithiated and then cooled to -78 degrees C. Solid carbon dioxide (5 g) was added in one portion and the solution was allowed to warm to room temperature. The solution was again cooled to 0 degrees C, quenched with diluted hydrochloric acid and twice extracted with tert-butyl methylether (TBME). The combined organic phases are washed with brine, dried over sodium sulfate and evaporated to dryness. Acetic anhydride (50 ml) was added to the residue and the suspension was refluxed for 2 hours. After cooling down the slurry was extracted several times with hexane, the combined hexane phases were evaporated to dryness and further dried to give 3,7-dihexyl-2,8-bis-trimethylsilanyl-dithieno(3,2-c;2',3'-e)oxepine-4,6-dione (16a). (16a) was dissolved in tetrahydrofuran, treated at 0 degrees C with hexylamine (2.2 equivalents) and stirred for 1 hour. After standard work-up (TBME, diluted hydrochloric acid, brine), the residue was suspended in acetic acid, treated with 10 equivalents each of acetic anhydride and sodium acetate and refluxed for 16 hours. Then most of the solvent was evaporated and the residue suspended in aqueous sodium bicarbonate, followed by extraction with TBME. The combined organic layers were washed with brine, dried and evaporated to dryness to give 3,5,7-trihexyl-2,8-bis-trimethylsilanyl-dithieno(3,2-c;2',3'-e)azepine-4,6-dione (7.6 g).