TECHNOLOGY FOCUS - POLYMERS - Preferred Components: The conjugated polymer comprises: solubilizing side groups; at least one polythiophene (preferred) (which is 3-substituted polythiophene or regioregular polythiophene), polyaniline, polypyrrole, polyphenylene vinylene, polyfluorene, polyphenylene, poly(thienylene vinylene), poly(bis-thienylene vinylene), poly(acetylene), poly(arylene) and/or poly(isothianaphthalene); and a homopolymer, copolymer, terpolymer, random copolymer, block copolymer or alternating copolymer. The polymer has a number average molecular weight of at least 2000, 5000 or 20000 g/mole. The polymer comprises: a backbone comprising at least ten conjugated repeat units; and at least two different porphyrinic macrocycles different from each other and each bonded to at least one conjugated polymer. The porphyrinic macrocycle is bonded to an end or side group of the conjugated polymer. Preferred Components: The porphyrinic macrocycle comprises: chlorin, bacteriochlorin (both preferred) or porphyrin. The porphyrinic macrocycle is: linked to the polymer by a spacer group. In (I): one porphyrinic macrocycle is bonded to one chain of the conjugated polymer; one porphyrinic macrocycle is bonded to at least two chains of the conjugated polymer; and one porphyrinic macrocycle is bonded to four chains of the conjugated polymer. The porphyrinic macrocycle and the polymer are linked by an ester linkage, amide linkage, ether linkage, urethane linkage, amino linkage, thioether linkage or thioester linkage. (I) further comprises: an n-type acceptor material; and a fullerene or a fullerene derivative. The porphyrinic macrocycle comprises metal. The device further comprises: a hole injection layer between one electrode and the active layer; a polythiophene hole injection layer between one electrode and the active layer. The semiconductor is a conjugated polymer and the additive is a porphyrinic macrocycle. The active layer further comprises a fullerene or fullerene derivative. The porphyrinic macrocycle comprises a moiety of formulae (a), (b) and/or (c). (I) is soluble.K1-K4 = selenium, NH, CH2, O or S; and eitherS1-S16 = H, alkenyl, alkynyl, (cyclo)alkyl, cycloalkylalkyl, cycloalkylalkenyl, cycloalkylalkynyl, heterocyclo, heterocycloalkyl, heterocycloalkenyl, heterocycloalkynyl, aryloxy, arylalkyl, arylalkenyl, arylalkynyl, (hetero)aryl, heteroarylalkyl, heteroarylalkenyl, heteroarylalkynyl, alkoxy, halo, mercapto, azido, CN, acyl, formyl, carboxylic acid, acylamino, ester, amide, imide, OH, nitro, alkylthio, (alkyl)amino, arylalkylamino, disubstituted amino, acyloxy, sulfoxyl, sulfonyl, sulfonate, sulfonamide, thiocyanato, urea, alkoxylacylamino or aminoacyloxy; andS8S14, S7S13, S3S15, S4S16 = O or spiroalkyl; orS1S2, S3S4, S5S6, S7S8 = annulated arene (optionally substituted by H, alkenyl, alkynyl, (cyclo)alkyl, cycloalkylalkyl, cycloalkylalkenyl, cycloalkylalkynyl, heterocyclo, heterocycloalkyl, heterocycloalkenyl, heterocycloalkynyl, aryloxy, arylalkyl, arylalkenyl, arylalkynyl, (hetero)aryl, heteroarylalkyl, heteroarylalkenyl, heteroarylalkynyl, alkoxy, halo, mercapto, azido, CN, acyl, formyl, carboxylic acid, acylamino, ester, amide, imide, OH, nitro, alkylthio, (alkyl)amino, arylalkylamino, disubstituted amino, acyloxy, sulfoxyl, sulfonyl, sulfonate, sulfonamide, thiocyanato, urea, alkoxylacylamino or aminoacyloxy). EXAMPLE - Thiopene polymer compound of formula (d) (30 mg), 5,15-bis(4- ethynylphenyl)-10,20-dimesitylporphyrin (2 mg), tetrakis(triphenyl phosphine) palladium (0.5 mg), and tri-o-tolyl phosphine (1.3 mg) were placed into flask. The flask was pump-purged with argon three times. Toluene/triethyl amine (1.1 ml, 5:1) was added, and the mixture was stirred at 50 degrees C under argon for 20 hours to give the polymer and porphyrin in a 1:1 ratio.