Suppression of electron and hole overflow in GaN-based near-ultraviolet laser diodes

• Published in: Chinese physics B 2018-02, Vol.27 (2), p.588-593
• Main Authors: 邢瑶, 赵德刚, 江德生, 李翔, 刘宗顺, 朱建军, 陈平, 杨静, 刘炜, 梁锋, 刘双韬, 张立群, 王文杰, 李沫, 张源涛, 杜国同
• Format: Article
• Language: English
• Subjects: 激光二极管; 电子漏; 紫外; 溢出; 陷阱; 类型区; 数字模拟; 阀值电流
• ISSN: 1674-1056; 2058-3834
• DOI: 10.1088/1674-1056/27/2/028101

In order to suppress the electron leakage to p-type region of near-ultraviolet GaN/In_xGa_（1-x ）N/GaN multiple-quantumwell（MQW） laser diode（LD）, the Al composition of inserted p-type AlxGa_（1-x）N electron blocking layer（EBL） is optimized in an effective way, but which could only partially enhance the performance of LD. Here, due to the relatively shallow GaN/In_（0.04）Ga_（0.96）N/GaN quantum well, the hole leakage to n-type region is considered in the ultraviolet LD. To reduce the hole leakage, a 10-nm n-type Al_xGa_（1-x）N hole blocking layer（HBL） is inserted between n-type waveguide and the first quantum barrier, and the effect of Al composition of Al_xGa_（1-x）N HBL on LD performance is studied. Numerical simulations by the LASTIP reveal that when an appropriate Al composition of Al_xGa_（1-x）N HBL is chosen, both electron leakage and hole leakage can be reduced dramatically, leading to a lower threshold current and higher output power of LD.