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ABSTRACTOwing to its wide bandgap (3.4 eV) and high electron mobility, GaN has attracted significant attention for applications in solar cells, power transistors, and high-electron-mobility transistors. Crystallized GaN thin film can be hardly prepared in thin film form by employing physical vapor deposition processes, such as reactive RF sputtering and pulsed laser deposition, because a high driving energy is required to deposit a thin film due to its high binding energy. Herein, GaN thin films were prepared by CO2 laser-assisted RF sputtering at a relatively low temperature of 200°C. The CO2 laser with a 10,600 nm wavelength shows excellent conversion efficiency from optical energy to thermal energy. At the optimized laser energy density of 0.98 W/mm2, GaN thin film can have a (0002) orientation with a bandgap energy of 3.26 eV. The crystalline, surface morphological, and optical properties of the fabricated GaN thin films were evaluated using X-ray diffraction, FE-SEM, X-ray photoelectron (XPS), and photoluminescence (PL) spectroscopy, and UV-vis spectrometry. The energy bandgap of the fabricated GaN thin film was measured using the Tauc plot and confirmed via PL. The film composition thus obtained was analyzed using XPS.