Photoexcitation dominated electrical behaviors in a nano GaN PN junction

In this paper, we investigate the regulation behaviors of photoexcited nonequilibrium carriers in a GaN piezoelectric semiconductor PN junctions. It is shown that the electromechanical field of the PN junction has a fast response to the illumination intensity. This is attributed to the ultraviolet photoexcited non-equilibrium carriers, which can shield the piezoelectric charges and significantly weaken the built-in barrier height. Furthermore, the electrical transmission characteristics are also regulated. It implies that the electrical behaviors of a nano GaN PN junctions are highly sensitive to ultraviolet light, and such a contactless approach can be applied to control the nano GaN devices.