An improved multi-layer stopper in a GaN-based laser diode

摘要

In pursuit of a more efficient GaN-based laser diode, a multi-layer structure has recently been proposed to replace the traditional single AlGaN layer as a stopper layer in order to control electron overflow. Based upon the multi-layer idea, this paper combines the Poisson-Schroedinger self-consistent method and the transfer matrix method to investigate the transport properties of the stopper layer under polarization both for the electron and the hole. Two new structures proposed by references are compared with the original one. The reason for a better structure is analyzed and the conclusion is drawn that the multi-layer structure can improve the hole transport. Also, a varied Al content multi-layer structure is theoretically calculated. The Al content for AlGaN layers is gradually increased from the active region to give a better performance both for the purpose of electron blocking and hole tunneling.