Optimization of Chemical Bath Deposited Mercury Chromium Sulphide Thin Films on Glass Substrate

Semiconducting thin films of ternary ( ) have been deposited on glass substrate by the simple and economical chemical bath deposition method. We report the deposition and optimization of the solution growth parameters such as temperature, complexing agent, thiourea, and deposition time that maximizes the thickness of the deposited thin film. The X-ray diffraction deposited thin films having cubic structure. The thin films were uniform and adherent to substrate. The composition was found homogeneous and stoichiometric by EDAX analysis. 1. Introduction Mercury chromium sulfide (HgCr2S4) is a chalcogenide metal sulfide semiconductor of the II–VI group compound semiconductors. The technological interests in polycrystalline-based devices are mainly caused by their low production cost [1]. The use of HgCr2S4 thin films of semiconductor has attracted much interest because of their role in variety of applications in various magneto-optical and optoelectronics devices [2] as well as magnetocapacitive or magnetoelectric effect devices [3–7]. Many techniques have been reported in the deposition of thin films such as evaporation, sputtering, spray pyrolysis, molecular beam epitaxy, and photochemical deposition. There is a problem in each of these deposition methods [8, 9]. Amongst all, chemical bath deposition (CBD) is simple and of low cost and is suitable for a large area deposition [10]. Thin films of diluted magnetic semiconductors attract many researchers due to their wide range of applications in various fields. The films of HgCr2S4 are usually crystallized in cubic structure with lattice constants 10.2？？ [11]. In the present study, the chemical bath process is performed by slow release of S2？ ions and controlled free Hg2+ and Cr2+ ions that react to form HgCr2S4 nuclei on glass substrate and in the bath solution in the form of precipitation. The properties of the deposited thin films basically depend on the deposition parameters such as deposition temperature, complexing agent, thiourea, deposition time, pH value, composition of materials, and film thickness. Finally, we report the deposition of HgCr2S4 thin films and the investigation of the different deposition parameters to obtain uniform film having expected thickness. 2. Materials and Methods In the present investigation, thin films of are grown on glass substrate by chemical bath deposition technique. All AR grade chemicals from MERCK are used for growth of thin films. For the deposition of , solutions of HgCl2, CrO3, and NH2-CS-NH2 are prepared separately of concentration 0.1？M using double distilled