“…Here, the high-resolution XPS spectra of the O 1s orbital in different films were analyzed in detail (Figure d–f). The O 1s XPS spectra of all the films are divided by Gaussian fitting into the O ion region (O I ) with a 530.6 eV center peak, the oxide defect (O II ) region with a 531.2 eV center peak, and the oxygen ion regions (O III ) with a 532.1 eV center peak, associated with carbon and hydroxyl groups adsorbed on the film surface. , Through Gaussian fitting, the intensity ratios of O II /(O I + O II ) in the O 1s spectra of the original film, the 600 °C annealed film, and the 800 °C annealed film are 77.49, 43.31, and 29.72%, respectively, which means the 800 °C annealed film has the least oxygen vacancy. , Next, a fitting method like that used in O 1s spectrum is applied to O 1s spectrum in Ga 2 O 3 films (Figure g–i). From the diagram, the content of oxygen-containing groups (OCG) decreases with the increase of annealing temperature, indicating that organic matter decomposes more thoroughly at higher temperatures.…”