GaN thin film: Growth and Characterizations by Magnetron Sputtering

In this article, growth of GaN thin film on low-cost electronic substrate (n-Si) by magnetron sputtering method was reported. Growth parameters of GaN thin film have been studied based on different flow rate of sputtering gasses, chamber pressure, sputtering power, substrate temperature and duty ratio of pulse signals. Characterization techniques such as X-ray diffraction (XRD), micro photoluminescence (µ-PL), raman spectroscopy, transmittance, X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) were performed to explore the optical and structural properties. XRD studies confirmed the wurtzite structure of grown thin film with the preferentially orientation along (002) plane, it also reveals the effect of growth parameters on the grain size and crystal quality of thin films. E2 (high) and A1 (LO) modes were observed in raman spectrum. Room temperature µ-PL and optical transmittance shows the near band edge (NBE) and sharp transmission edge around ∼3.3 eV relates to the band gap value of GaN structure.