Successful growth of Zinc Nitride thin films by vacuum tube furnace using nitrogen as source gas

Abstract

We have successfully grown Zn3N2 thin films using a simple and cost effective approach. Growth was achieved in a vacuum tube furnace by evaporating Zinc powder at 850 OC and flowing nitrogen gas into the tube at the rate of 150 sccm. After achieving evaporation temperature of 850 OC in the tube, nitrogen gas was filled in the vacuum tube having working pressure of 5 atm and then system was kept in the nitrogen environment for 1 h at a constant flow rate of 150 sccm. In order to grow quality thin films, a bunch of samples were grown by varying the various growth parameters during the growth process. The first batch of samples was grown using different source to substrate distances (21–25 cm with a step of 2 cm) and pieces of a representative sample were post growth annealed in a nitrogen environment in the temperature range 350–600 °C. The obtained Zn3N2 thin films were characterized by X-Ray Diffraction, UV/Vis spectroscopy and Scanning Electron Microscope (SEM). XRD data showed a strong peak at 36.60° which is related to the (400) plan of pure Zn3N2 for all samples along with some additional peaks due to Zn structure. The optimum values of source to substrate distance and post growth annealing temperature are found to be 23 cm and 600 °C respectively.