In‐situ boron doping of chemical‐bath deposited CdS thin films

Abstract

Abstract In‐situ boron doping of CdS using chemical‐bath deposition (CBD) is reported. The effect of B doping on optical properties, as well as electrical properties, crystal structure, chemistry, and morphology of CdS films is studied. We present a successful approach towards B doping of CdS using CBD, where a resistivity as low as 1.7 × 10 –2 Ω cm and a carrier density as high as 1.91 × 10 19 cm –3 were achieved. The bandgap of B‐doped films was found to slightly decrease as the [B]/[Cd] ratio in the solution increases. X‐ray diffraction studies showed B 3+ ions likely enter the lattice substitutionally. A phase transition, due to annealing, as well as induced lattice defects, due to B doping, were detected by micro‐Raman spectroscopy and transmission electron microscopy. The chemistry and morphology of films were unaffected by B doping. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)