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Selectively Enhanced UV-A Photoresponsivity of a GaN MSM UV Photodetector with a Step-Graded Al(x)Ga(1−x)N Buffer Layer

The UV-to-visible rejection ratio is one of the important figure of merits of GaN-based UV photodetectors. For cost-effectiveness and large-scale fabrication of GaN devices, we tried to grow a GaN epitaxial layer on silicon substrate with complicated buffer layers for a stress-release. It is known t...

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Autores principales: Lee, Chang-Ju, Won, Chul-Ho, Lee, Jung-Hee, Hahm, Sung-Ho, Park, Hongsik
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2017
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5539806/
https://www.ncbi.nlm.nih.gov/pubmed/28753989
http://dx.doi.org/10.3390/s17071684
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author Lee, Chang-Ju
Won, Chul-Ho
Lee, Jung-Hee
Hahm, Sung-Ho
Park, Hongsik
author_facet Lee, Chang-Ju
Won, Chul-Ho
Lee, Jung-Hee
Hahm, Sung-Ho
Park, Hongsik
author_sort Lee, Chang-Ju
collection PubMed
description The UV-to-visible rejection ratio is one of the important figure of merits of GaN-based UV photodetectors. For cost-effectiveness and large-scale fabrication of GaN devices, we tried to grow a GaN epitaxial layer on silicon substrate with complicated buffer layers for a stress-release. It is known that the structure of the buffer layers affects the performance of devices fabricated on the GaN epitaxial layers. In this study, we show that the design of a buffer layer structure can make effect on the UV-to-visible rejection ratio of GaN UV photodetectors. The GaN photodetector fabricated on GaN-on-silicon substrate with a step-graded Al(x)Ga(−x)N buffer layer has a highly-selective photoresponse at 365-nm wavelength. The UV-to-visible rejection ratio of the GaN UV photodetector with the step-graded Al(x)Ga(1−x)N buffer layer was an order-of-magnitude higher than that of a photodetector with a conventional GaN/AlN multi buffer layer. The maximum photoresponsivity was as high as 5 × 10(−2) A/W. This result implies that the design of buffer layer is important for photoresponse characteristics of GaN UV photodetectors as well as the crystal quality of the GaN epitaxial layers.
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spelling pubmed-55398062017-08-11 Selectively Enhanced UV-A Photoresponsivity of a GaN MSM UV Photodetector with a Step-Graded Al(x)Ga(1−x)N Buffer Layer Lee, Chang-Ju Won, Chul-Ho Lee, Jung-Hee Hahm, Sung-Ho Park, Hongsik Sensors (Basel) Article The UV-to-visible rejection ratio is one of the important figure of merits of GaN-based UV photodetectors. For cost-effectiveness and large-scale fabrication of GaN devices, we tried to grow a GaN epitaxial layer on silicon substrate with complicated buffer layers for a stress-release. It is known that the structure of the buffer layers affects the performance of devices fabricated on the GaN epitaxial layers. In this study, we show that the design of a buffer layer structure can make effect on the UV-to-visible rejection ratio of GaN UV photodetectors. The GaN photodetector fabricated on GaN-on-silicon substrate with a step-graded Al(x)Ga(−x)N buffer layer has a highly-selective photoresponse at 365-nm wavelength. The UV-to-visible rejection ratio of the GaN UV photodetector with the step-graded Al(x)Ga(1−x)N buffer layer was an order-of-magnitude higher than that of a photodetector with a conventional GaN/AlN multi buffer layer. The maximum photoresponsivity was as high as 5 × 10(−2) A/W. This result implies that the design of buffer layer is important for photoresponse characteristics of GaN UV photodetectors as well as the crystal quality of the GaN epitaxial layers. MDPI 2017-07-21 /pmc/articles/PMC5539806/ /pubmed/28753989 http://dx.doi.org/10.3390/s17071684 Text en © 2017 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Lee, Chang-Ju
Won, Chul-Ho
Lee, Jung-Hee
Hahm, Sung-Ho
Park, Hongsik
Selectively Enhanced UV-A Photoresponsivity of a GaN MSM UV Photodetector with a Step-Graded Al(x)Ga(1−x)N Buffer Layer
title Selectively Enhanced UV-A Photoresponsivity of a GaN MSM UV Photodetector with a Step-Graded Al(x)Ga(1−x)N Buffer Layer
title_full Selectively Enhanced UV-A Photoresponsivity of a GaN MSM UV Photodetector with a Step-Graded Al(x)Ga(1−x)N Buffer Layer
title_fullStr Selectively Enhanced UV-A Photoresponsivity of a GaN MSM UV Photodetector with a Step-Graded Al(x)Ga(1−x)N Buffer Layer
title_full_unstemmed Selectively Enhanced UV-A Photoresponsivity of a GaN MSM UV Photodetector with a Step-Graded Al(x)Ga(1−x)N Buffer Layer
title_short Selectively Enhanced UV-A Photoresponsivity of a GaN MSM UV Photodetector with a Step-Graded Al(x)Ga(1−x)N Buffer Layer
title_sort selectively enhanced uv-a photoresponsivity of a gan msm uv photodetector with a step-graded al(x)ga(1−x)n buffer layer
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5539806/
https://www.ncbi.nlm.nih.gov/pubmed/28753989
http://dx.doi.org/10.3390/s17071684
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