Open AccessPerformance enhancement of AlGaN/InGaN MQW LED with GaN/InGaN superlattice structure
Author(s) -
Saroosh Rabia,
Tauqeer Tauseef,
Afzal Sara,
Mehmood Haris
Publication year - 2017
Publication title -
iet optoelectronics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.379
H-Index - 42
eISSN - 1751-8776
pISSN - 1751-8768
DOI - 10.1049/iet-opt.2016.0141
Subject(s) - materials science , optoelectronics , superlattice , light emitting diode , gallium nitride , epitaxy , diode , nitride , indium gallium nitride , layer (electronics) , nanotechnology
A gallium nitride (GaN)‐based light‐emitting diode (LED) structure with 10‐period superlattice layers (SLs) of p ‐GaN/ i ‐In 0.2 Ga 0.8 N, inserted between p ‐GaN and 12‐period Al 0.16 Ga 0.84 N/In 0.2 Ga 0.8 N multiple quantum well (MQW) layers, is numerically designed and examined using physical device simulator, SILVACO. The SL structure acts as a confinement layer of holes that serves to mitigate the effects of efficiency droop and leakage current within LED. Consequently, inserting SL structure within epitaxial domain tends to improve the current‐spreading capability of the device. The proposed structure is compared with the conventional LED without SL and enhanced LED performance has been demonstrated by the SL‐based device. The measured power spectral density and luminous power of the under‐investigated device are 8.27 W/cm eV at 433 nm and 3.1 W/cm at 12.32 kA/cm 2 , respectively. Correspondingly, the external QE of 25.4% has been determined that is higher than the earlier LED reported with 10‐period SL structure of p ‐GaN/ i ‐In 0.2 Ga 0.8 N and 12‐period MQWs of GaN/indium GaN configuration. Moreover, another structure based on 30‐period SL was also investigated and the output results exhibited no significant improvement in the efficiency due to thermionic emission and thickness‐induced strain factors.