Influences of screw dislocations on electroluminescence of AlGaN/AlN-based UVC LEDs
We investigated two types of threading dislocations in high Al-composition Al0.55Ga0.45N/AlN multiple quantum well (MQW) structures grown on AlN substrate for electrically injected deep ultraviolet light-emitting diodes (LEDs). The surface morphology and defects electrical characteristics of the MQW...
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Language: | English |
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AIP Publishing LLC
2019-08-01
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Series: | AIP Advances |
Online Access: | http://dx.doi.org/10.1063/1.5108743 |
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author | Dong Liu Sang June Cho Huilong Zhang Corey R. Carlos Akhil R. K. Kalapala Jeongpil Park Jisoo Kim Rafael Dalmau Jiarui Gong Baxter Moody Xudong Wang John D. Albrecht Weidong Zhou Zhenqiang Ma |
author_facet | Dong Liu Sang June Cho Huilong Zhang Corey R. Carlos Akhil R. K. Kalapala Jeongpil Park Jisoo Kim Rafael Dalmau Jiarui Gong Baxter Moody Xudong Wang John D. Albrecht Weidong Zhou Zhenqiang Ma |
author_sort | Dong Liu |
collection | DOAJ |
description | We investigated two types of threading dislocations in high Al-composition Al0.55Ga0.45N/AlN multiple quantum well (MQW) structures grown on AlN substrate for electrically injected deep ultraviolet light-emitting diodes (LEDs). The surface morphology and defects electrical characteristics of the MQW LED structures were examined via conductive atomic force microscopy (CAFM). We found that the disparity between photoluminescence (PL) and electroluminescence (EL) spectra in terms of light emission output and wavelength shift are attributed to the existence of the surface hillocks, especially to the ones that have open-core dislocations. The open-core dislocations form current leakage paths through their defect states and the composition inhomogeneity (i.e., Ga rich) at the dislocation sites are responsible for the light emission at longer wavelengths. |
first_indexed | 2024-04-13T19:14:48Z |
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institution | Directory Open Access Journal |
issn | 2158-3226 |
language | English |
last_indexed | 2024-04-13T19:14:48Z |
publishDate | 2019-08-01 |
publisher | AIP Publishing LLC |
record_format | Article |
series | AIP Advances |
spelling | doaj.art-90b50bba57e543f78a4e133449b42ccc2022-12-22T02:33:43ZengAIP Publishing LLCAIP Advances2158-32262019-08-0198085128085128-610.1063/1.5108743114908ADVInfluences of screw dislocations on electroluminescence of AlGaN/AlN-based UVC LEDsDong Liu0Sang June Cho1Huilong Zhang2Corey R. Carlos3Akhil R. K. Kalapala4Jeongpil Park5Jisoo Kim6Rafael Dalmau7Jiarui Gong8Baxter Moody9Xudong Wang10John D. Albrecht11Weidong Zhou12Zhenqiang Ma13Department of Electrical and Computer Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, USADepartment of Electrical and Computer Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, USADepartment of Electrical and Computer Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, USADepartment of Material Science Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, USADepartment of Electrical Engineering, University of Texas at Arlington, 500 South Cooper Street, Arlington, Texas 76019, USADepartment of Electrical and Computer Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, USADepartment of Electrical and Computer Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, USAHexaTech, Inc., 991 Aviation Parkway, Suite 800, Morrisville, North Carolina 27560, USADepartment of Electrical and Computer Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, USAHexaTech, Inc., 991 Aviation Parkway, Suite 800, Morrisville, North Carolina 27560, USADepartment of Material Science Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, USADepartment of Electrical and Computer Engineering, Michigan State University, 428 S. Shaw Lane, East Lansing, Michigan 48824, USADepartment of Electrical Engineering, University of Texas at Arlington, 500 South Cooper Street, Arlington, Texas 76019, USADepartment of Electrical and Computer Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, USAWe investigated two types of threading dislocations in high Al-composition Al0.55Ga0.45N/AlN multiple quantum well (MQW) structures grown on AlN substrate for electrically injected deep ultraviolet light-emitting diodes (LEDs). The surface morphology and defects electrical characteristics of the MQW LED structures were examined via conductive atomic force microscopy (CAFM). We found that the disparity between photoluminescence (PL) and electroluminescence (EL) spectra in terms of light emission output and wavelength shift are attributed to the existence of the surface hillocks, especially to the ones that have open-core dislocations. The open-core dislocations form current leakage paths through their defect states and the composition inhomogeneity (i.e., Ga rich) at the dislocation sites are responsible for the light emission at longer wavelengths.http://dx.doi.org/10.1063/1.5108743 |
spellingShingle | Dong Liu Sang June Cho Huilong Zhang Corey R. Carlos Akhil R. K. Kalapala Jeongpil Park Jisoo Kim Rafael Dalmau Jiarui Gong Baxter Moody Xudong Wang John D. Albrecht Weidong Zhou Zhenqiang Ma Influences of screw dislocations on electroluminescence of AlGaN/AlN-based UVC LEDs AIP Advances |
title | Influences of screw dislocations on electroluminescence of AlGaN/AlN-based UVC LEDs |
title_full | Influences of screw dislocations on electroluminescence of AlGaN/AlN-based UVC LEDs |
title_fullStr | Influences of screw dislocations on electroluminescence of AlGaN/AlN-based UVC LEDs |
title_full_unstemmed | Influences of screw dislocations on electroluminescence of AlGaN/AlN-based UVC LEDs |
title_short | Influences of screw dislocations on electroluminescence of AlGaN/AlN-based UVC LEDs |
title_sort | influences of screw dislocations on electroluminescence of algan aln based uvc leds |
url | http://dx.doi.org/10.1063/1.5108743 |
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