Characterization of thermally evaporated AgGaTe2 films

Silver gallium telluride (AgGaTe2) films were prepared by thermal evaporati on technique in vacuum of the order of 10(-5) torr. onto the glass substrat e kept at different temperatures. The electrical conductivity, Hall coeffic ient and carrier concentration of these films have been investigated in the temperature range 193-413 K. The films appear to be p-type thus indicating holes as dominant charge carriers and the films show comparatively higher conductivity at higher substrate temperature. An increase in temperature in creases the electrical conductivity, while decrease in Hall coefficient wit h temperature has been observed. Scanning electron micrographs show an incr ease in grain size with substrate temperature thus indicating it to be a mo re ordered system. Optical band gap of the films lies in the range 1.58-1.8 9 eV.