Growth of ZnSe thin layers on different substrates and their structural consequences with bath temperature

Abstract

Refractory zinc selenide (ZnSe) semiconductor thin films have been prepared for different thicknesses by cathodic electrodeposition from aquatic solution containing SeO 3 2− and Zn 2+. A systematic study on the structural evolution of ZnSe on various commercially pure substrates, titanium (Ti), stainless steel (SS) and aluminium (Al) has been studied in the working solution at different bath temperatures (333, 343 and 353 K). Thickness of the films was monitored and was found to be in the range 1–5 μm depending on the substrate used. At high temperature depositions (>333 K), nanocrystalline cubic ZnSe ( a=5.8814 Å) thin films on titanium substrates with smaller grain size of about 30–80 nm were observed. Other related structural parameters such as dislocation density, microstrain, number of crystallites per unit area were evaluated from the X-ray diffraction data. The ZnSe films deposited over SS and Al substrates were crystalline and were indexed for hexagonal lattice. The outcome of the preparation process has been analyzed for the suitability of engaged substrates for the production of high quality single phase ZnSe films. The grain orientations on the surface were examined using atomic force microscopy and the observed grain size was compared with those evaluated through X-ray diffraction analysis.