Experimental Investigation of FTIR Absorbance Versus Deposition Temperature of Vapour-Deposited Zinc Oxide Thin Films

Abstract

Zinc oxide thin films were deposited on soda-lime glass substrates using the metalorganic chemical vapour deposition (MOCVD) method with zinc acetate as the precursor at temperatures of 330°C, 360°C, 390°C, and 420°C. The carrier gas was compressed air at a flow rate of 2.5 dm3 per minute. Each deposition lasted two hours and was done at atmospheric pressure. Following that, FTIR measurements were taken on the thin films to establish their structure and trend with deposition temperatures. Fourier Transform Infrared (FTIR) spectroscopy is a simple, non-destructive technique used to identify all the elements in a material.  The measurements revealed the presence of lingering functional groups of organic, oxide and nitride origin, which prominently moderated the natural vibrational modes of the material within their respective affiliate wavenumbers, as well as three slight but evident trends in absorbance peaks, cut-off wave- length, and the existence of the functional groups with temperature. The materials created are predicted to be beneficial for improved solar cells, triggering sensor devices, p-doped zinc oxide, and other applications.