EVAPORATED III-VI SEMICONDUCTOR LAYERS FOR CHALCOGENIDE-BASEDTHIN FILM SOLAR CELLS

摘要

Various III-VI semiconductor layers have been obtained on glass substrates by In and/or Gaevaporation and subsequent heating in elemental Se or S atmosphere at temperatures between 250 and 400 °C. Theinfluence of the constituents, heating temperature and film thickness on the crystalline structure and opticalproperties of the layers has been established. X-ray diffraction analyses have indicated that indium selenide andindium sulfide polycrystalline thin films can be obtained at substrate temperatures as low as 250 °C, the formation ofgallium selenide and gallium sulfide compounds requiring temperatures above 350 °C. The optical measurements ofthe evaporated semiconductor samples with 130 nm thickness have shown energy gap values ranging from 2.0 eV forindium selenide to 2.5 eV for gallium sulfide. For the different thin film evaporated compounds, the band gap and theoptical transmittance increase as the layer thickness decreases.