LAUSR

Abstract Doping is a prevalent technique for improving the optoelectronic properties of semiconductor thin films. Bismuth (Bi) doped nanocrystalline cadmium selenide thin films deposited on glass substrates were prepared by a chemical deposition method. The effect of different doping percentages of Bi has been investigated in detail. X-ray diffraction, high-resolution transmission electron microscopy, scanning electron microscopy, energy dispersive x-ray analysis, electrical techniques, optical absorption, photoluminescence, Raman spectroscopy, and water wettability measurement were used to characterize the films. X-ray diffraction showed the formation of a polycrystalline CdSe cubic phase with the preferential orientation (111). The optical band gap values decreased as the Bi doping concentration increased. The high optical band gap of the films up to 2.62 eV showed a strong blue shift. Films were luminescent with emission in the green region when they were excited with a UV source. The resistivity of the thin films was found to decrease with increase in Bi concentration. Surface morphology showed an almost uniform distribution of spherical grains. Water wettability analysis showed that the films were purely hydrophilic. Raman analysis confirmed the formation of nanocrystalline CdSe thin films.