Electrochemical growth and characterization of manganese telluride thin films

A novel method for electrochemical deposition of manganese telluride (MnTe) thin film from an aqueous acidic bath is described. Anodic oxidation of Mn has been controlled using tartaric acid and the inhibitive action was studied via cyclic voltammetric studies. In order to optimize film deposition in stoichiometric concentrations, the initial concentrations of precursor chemicals in the solution are determined from the current potential relationship based on a current model under diffusion control. X-ray diffraction revealed the formation of polycrystalline manganese telluride films. Compositional analysis showed the dependence of [Mn]/[Te] ratio on the applied potential for deposition. Variation of deposited mass with the electrical charge passed was studied in support of the reaction mechanism and was found in good agreement with the film thickness. Two direct optical energy gaps at 1.25 and at 1.5 eV were observed in the film deposited at −0.75 V (SCE), where as only one gap at 1.25 eV was observed in film electrodeposited at −0.65 V.