Effect of substrate temperature on structural, morphological, and optical properties of Gallium Oxide thin films deposited by RF-Sputtering

Abstract

In this paper, gallium oxide (Ga2O3) thin films at various substrate temperatures (Ts) were grown on Indium Tin Oxide (ITO), glass, p-type silicon by radio-frequency magnetron sputtering (RFMS). We investigated how structural, morphological and optical properties change with various Ts. XRD results of thin films grown on p-type silicon substrate suggest that crystallinity properties of synthesized thin films strongly depend on the Ts. From SEM and AFM analyses of Ga2O3 thin films grown on p-type silicon substrate, it was observed that when the temperature increased, a porous structure appeared, and the grain size changed depending on the Ts. Moreover, obtained results from the absorption measurements, the bandgap energy of Ga2O3 thin films grown on the p-type silicon substrate decreased with increasing substrate temperature.

Keywords

• Gallium oxide
• Thin film
• Sputter
• Nano structure

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