TECHNOLOGY FOCUS - POLYMERS - Preferred Polymer: (O) is a high molecular film selected from polyvinyl carbazole, poly(p-phenylene)-vinylene, polyaniline, polyethylene oxide, polyvinyl pyridine, polyvinyl alcohol, polythiophene, polyfluorene or polyparaphenylene. It may also be obtained by polymerizing a derivative of at least one monomer starting material of these polymers. A dopant may be added to control the electrical conductivity of the film.Preferred Fullerene: The fullerene is C60 and/or C70. A vapor-deposited film of specified thickness is polymerized. The film thickness is measured by a meter in a vacuum chamber. The electromagnetic waves are RF plasma, UV rays or electron rays. The polymer may also be formed by photo-, microwave or electrolytic polymerization. The polymer is identified by the Raman and/or Nexafs (Near-Edge X-ray Fine Structure) methods.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Electrodes: The electrodes are formed as thin films of metal oxide or metal. The light-transmitting electrode is preferably a metal oxide obtained on doping an indium oxide with tin, or a thin film of gold, silver, platinum or nickel. The counter-electrode is preferably a thin film of the metal oxide, aluminum, magnesium or indium.    TECHNOLOGY FOCUS - ELECTRONICS - Preferred Heterojunction: (F) is in contact with the counter-electrode. An active layer is interposed between (F) and (O). (O) has a covalent pi-electron system. The light-transmitting electrode, (O), (F) and the counter-electrode are layered in this order on the substrate. Alternatively, the light-transmitting electrode, (F), (O) and the counter-electrode are layered in this order. EXAMPLE - An ITO thin film was formed by sputtering on commercial quartz glass to form a light-transmitting electrode. A polythiophene thin film having a sulfur radical as dopant was then deposited. A mixture (9:1) of C60 and C70 fullerenes was vaporized and deposited on the substrate to a thickness of 30 nm while polymerization was effected by microwaves. The following properties were measured: electrical conductivity = 1.1 x 10 power-8 S/cm; band gap = 1.4 eV; dangling = 2.0 x 10 power18 spins/g.