| Popis: |
CuIn 1− x Ga x Se 2 (CIGS) thin films are being prepared by selenization of Cu–In–Ga precursors using diethylselenide, (C 2 H 5 ) 2 Se, (DESe) as selenium source in place of H 2 Se gas because of lower toxicity and ease of handling. Rough estimates indicate that selenization process using DESe would cost approximately same or slightly less compared to that using H 2 Se. Price of DESe per mole is approximately five times that of H 2 Se. However, partial pressure of DESe, which reflects source material consumption, is approximately three to four times less than that of H 2 Se, due to higher decomposition rate of DESe compared to that of H 2 Se. The actual DESe consumption would be four to ten times less compared to that of H 2 Se. A selenization set-up using DESe as selenium source has been designed, fabricated and installed at FSEC Photovoltaic Materials Lab. Initial characterization of CIGS thin films have been carried out using electron probe microanalysis (EPMA), X-ray diffraction (XRD), scanning electron microscopy, secondary ion mass spectroscopy and Auger electron spectroscopy. EPMA showed elemental ratios of film to be near stoichiometric composition CuInSe 2 with very low gallium content mainly because of tendency of gallium to diffuse towards back contact. XRD data shows formation of high crystalline CuInSe 2 phase consistent with the EPMA data. |
Full Text from ScienceDirect