Electrodeposition mechanism of ZnSe thin film in aqueous solution

ZnSe is one of the important and excellent II-VI semiconductor materials, which has direct transition band structure. In this paper, ZnSe thin films were prepared by an electrochemical deposition method, and the formation mechanism of ZnSe was studied systematically. Voltammerry and chronoamperometry combined with X-ray diffraction （XRD） and Raman techniques were used to analyze the deposition processes. It is found that the substrate and deposition potentials have a great influence on the phase composition of deposited thin film, and Zn substrate is beneficial to the preparation ZnSe films. Strong selenium-substrate interaction results in the formation of selenimn compounds involving electrode materials. The addition of Zn（II） source can affect the reduction potential of Se, and results in the change of reducing mechanism of Se（0） from Se（IV）. Se（0） formed from H2Se because the formation of H2Se is more active than forming Se（0） directly from Se（IV）, and H2Se can recombine with the substrate material, forming selenium-substrate compounds more quickly.