Low-temperature effect on GaN film in argon plasma

This journal article shows the effect of low temperature for gallium nitride (GaN) film in an argon plasma. Our first observation showed that the evolution of photoluminescence (PL) from the GaN film depends on the temperature of the film during the plasma exposure. The observation showed that the PL emission became approximately 35% of the original PL intensity for no-temperature-controlled (as-is) GaN film, while the emission became approximately 70% for low-temperature-regulated (cold) GaN film. The main difference between the two films was only in the temperature range during plasma exposure, but the temperature difference between pre- and post-plasma was almost the same for the two films. Then, we didex situx-ray photoelectron spectroscopy (XPS) analysis to investigate whether or not there was a difference in the depth profile of elements in the films. As a consequence, we concluded that the reduction of thermal energy during a plasma exposure could regulate the opportunities for the species transfer in the film, which can minimize the evolution of GaN film during the plasma process.