Title: Manipulation of nanoscale V-pits to optimize internal quantum efficiency of InGaN multiple quantum wells
Authors: Chang, Chiao-Yun
Li, Heng
Shih, Yang-Ta
Lu, Tien-Chang
Department of Photonics
Issue Date: 2-Mar-2015
Abstract: We systematically investigated the influence of nanoscale V-pits on the internal quantum efficiency (IQE) of InGaN multiple quantum wells (MQWs) by adjusting the underlying superlattices (SLS). The analysis indicated that high barrier energy of sidewall MQWs on V-pits and long diffusion distance between the threading dislocation (TD) center and V-pit boundary were crucial to effectively passivate the non-radiative centers of TDs. For a larger V-pit, the thicker sidewall MQW on V-pit would decrease the barrier energy. On the contrary, a shorter distance between the TD center and V-pit boundary would be observed in a smaller V-pit, which could increase the carrier capturing capability of TDs. An optimized V-pit size of approximately 200-250 nm in our experiment could be concluded for MQWs with 15 pairs SLS, which exhibited an IQE value of 70%. (C) 2015 AIP Publishing LLC.
URI: http://dx.doi.org/10.1063/1.4914116
ISSN: 0003-6951
DOI: 10.1063/1.4914116
Volume: 106
Appears in Collections:Articles