Red light emitting diodes based on the type-II InGaN-ZnSnN2/GaN quantum wells

Several approaches have been tried by researchers for improvement of the InxGa1-xN/GaN QW red LEDs, where due the strong polarization fields, the electron-hole wave functions are separated spatially. In this paper, we have studied the type-II InGaN-ZnSnN2/GaN QW diodes and compared the results with the conventional InGaN/GaN QW diodes for red emission. It reveals that the overlap of electron- hole wave functions are increased more than three times that of the conventional InGaN/GaN QWs. In the active region with lower In-content, hole confinement increases due to higher valance band offset in the type-II structure and the electron-hole wave functions move towards the center of the well. The entire red region of the visible spectrum can be covered with suitable width, position of the ZnSnN2 layer and In content in the InGaN layer. The computations have been carried out through the self-consistent solutions of the Schrödinger and Poisson equations.