Numerical Study of Current Spreading and Light Extraction in Deep UV Light-Emitting Diode

The current crowding effect in AlGaN 275 nm deep UVLEDs has been investigated by using 2D drift diffusion solver and the Monte Carlo ray-tracing method. Optimized conditions for both lateral and vertical structure have been presented in this paper by changing the spacing between 2 fingers. To improve the light extraction efficiency, using graphene as the contact layer and removing the p-GaN layer have also been discussed here. Thus with the markable increasing of LEE, the external quantum efficiency can be improved to 37.8% in the textured vertical structure without p-GaN layer.