Constraints for ZnSe thin film growth and stoichiometry regulation

The main theme in thin film science is to control the stoichiometry of chemical constituents to form a quality yield supporting functional applications. Here, we have attempted the constraint formulation for stoichiometry regulation of ZnSe thin films by an industry preferred chemical deposition. The as-deposited films were characterized through the elemental, compositional, structural, morphological, optical and electrical transport studies. X-ray photoelectron spectroscopy confirmed the +2 and −2 oxidation states of Zn and Se in as-grown thin films. The compositional analysis further suggested near-stoichiometric film formation for TEA = 0.3 ml, NH₃ = 17 ml and N₂H₄ = 6 ml. Structural assessment confirmed the formation of poly-microcrystalline thin films with cubic zinc blend structure. Spherical crystallites with uneven intercrystalline spacing were observed in microstructural studies. Minor variation in the bandgap values was attributed to stoichiometric deviations and microstructural amendments. The electrical transport studies revealed temperature dependence of electrical conductivity.