Open AccessStrain relaxation of InGaN/GaN multi-quantum well light emitters via nanopatterning
Author(s) -
Ryan Ley,
Lesley Chan,
Pavel Shapturenka,
Matthew S. Wong,
Steven P. DenBaars,
Michael J. Gordon
Publication year - 2019
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.27.030081
Subject(s) - materials science , nanorod , photoluminescence , optoelectronics , inductively coupled plasma , blueshift , etching (microfabrication) , relaxation (psychology) , plasma etching , nitride , diffraction , optics , plasma , nanotechnology , layer (electronics) , psychology , social psychology , physics , quantum mechanics
Strain in InGaN/GaN multiple-quantum well (MQW) light emitters was relaxed via nanopatterning using colloidal lithography and top-down plasma etching. Colloidal lithography was performed using Langmuir-Blodgett dip-coating of samples with silica particles (d = 170, 310, 690, 960 nm) and a Cl 2 /N 2 inductively coupled plasma etch to produce nanorod structures. The InGaN/GaN MQW nanorods were characterized using X-ray diffraction (XRD) reciprocal space mapping to quantify the degree of relaxation. A peak relaxation of 32% was achieved for the smallest diameter features tested (120 nm after etching). Power-dependent photoluminescence at 13 K showed blue-shifted quantum well emission upon relaxation, which is attributed to reduction of the inherent piezoelectric field in the III-nitrides. Poisson-Schrödinger simulations of single well structures also predicted increasing spectral blueshift with strain relaxation, in agreement with experiments.