The Effect of AlN Epilayer Growth Rate on the Growth of Semipolar (11-22) InGaN/GaN Light Emitting Diode
Document Type
Article
Publication Date
11-1-2024
Abstract
This article presents the effect of aluminium nitride (AlN) epilayer (EPL) growth rate on the growth of semipolar (11-22) InGaN/GaN light emitting diode (LED). Three samples are grown with different AlN EPL growth rates, which are low (L1, 1.0 nm s-1), intermediate (L2, 1.3 nm s-1), and high (L3, 1.6 nm s-1) growth rate. The root-mean-square (RMS) and peak-to-valley roughness show an increasing trend with the increasing AlN EPL growth rate which is attributed to an increment in indium composition as justified by the photoluminescence results. The sample with AlN EPL growth rate of 1.3 nm s-1 (L2) exhibits an outstanding crystal quality in terms of defect densities reduction, with a minimum basal stacking fault density of 1.60 x 104 cm-1 as calculated. Besides that, the obvious fringes of InGaN/GaN peaks observed in 2 theta-omega scan proves that a high abruptness multi-quantum well is attained. Sample L2 also shows a single peak profile in both photoluminescence and electroluminescence spectra with green wavelength emission of 506 and 537 nm, respectively, indicating a homogeneous indium composition. As the injection current is swept from 5 to 40 mA for sample L2, a weak blueshift of approximate to 6 nm is observed which indicates a reduction in quantum-confined Stark effect (QCSE). Semipolar (11-22) InGaN/GaN LED with AlN epilayer grown at 1.3 nm s-1 displays excellent crystal quality, featuring a basal stacking fault density of 1.60 x 104 cm-1 and high abruptness multi-quantum well (MQW). Emitting a single green peak profile at 506 nm in photoluminescence and 537 nm in electroluminescence, a minor blueshift (approximate to 6 nm) in electroluminescence spectra suggests reduced quantum-confined Stark effect (QCSE).image (c) 2024 WILEY-VCH GmbH
Keywords
AlN epilayer growth rate, green emission, InGaN/GaN, light emitting diodes, semipolar (11-22)
Divisions
PHYSICS
Funders
Kementerian Sains, Teknologi dan Inovasi (MOSTI005-2021SRF),MIMOS SRF-APP grant (PV015-2015); (T13C2-17/PV007-2019),Ministry of Energy, Science, Technology, Environment and Climate Change (MESTECC), Malaysia,Collaborative Research in Engineering, Science and Technology Center (CREST)
Publication Title
Physica Status Solidi (B) – Basic Solid State Physics
Volume
261
Issue
11, SI
Publisher
Wiley
Publisher Location
POSTFACH 101161, 69451 WEINHEIM, GERMANY