Wide band gap p-type windows by CBD and SILAR methods

Department of Solar Energy Research, Hahn-Meitner-Institut, Glienicker Strasse 100, D-14109 Berlin, Germany
Thin Solid Films (Impact Factor: 1.87). 01/2004; DOI: 10.1016/j.tsf.2003.11.002

ABSTRACT Chemical deposition methods, namely, chemical bath deposition (CBD) and successive ionic layer adsorption and reaction (SILAR) have been used to deposit wide band gap p-type CuI and CuSCN thin films at room temperature (25 °C) in aqueous medium. Growth of these films requires the use of Cu (I) cations as a copper ions source. This is achieved by complexing Cu (II) ions using Na2S2O3. The anion sources are either KI as iodine or KSCN as thiocyanide ions for CuI and CuSCN films, respectively. The preparative parameters are optimized with the aim to use these p-type materials as windows for solar cells. Different substrates are used, namely: glass, fluorine doped tin oxide coated glass and CuInS2 (CIS). X-ray diffraction, scanning electron microscopy, atomic force microscopy and optical absorption spectroscopy are used for structural, surface morphological and optical studies, and the results are discussed.

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