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Title: Graphene-enhanced gallium nitride ultraviolet photodetectors under 2 MeV proton irradiation

Abstract

The electrical characteristics of gallium nitride (GaN) ultraviolet (UV) photodetectors with graphene and semitransparent Ni/Au electrodes subjected to 2 MeV proton irradiation are reported and compared. Graphene is shown to have a very high transmittance (87%) in the UV regime (365 nm) compared to semitransparent Ni/Au (3 nm / 10 nm) films (32%). Correspondingly, microfabricated graphene/GaN photodetectors showed a much higher pre-irradiation responsivity of 3388 A/W while that of semitransparent Ni/Au/GaN photodetectors was 351 A/W. For both types of electrodes, intermittent current-voltage measurements made during 2 MeV proton irradiation showed minimal variation up to a fluence of approximately 3.8 × 10 13 cm -2. Additionally, Raman spectroscopy of 200 keV proton beam, 3.8 × 10 13 cm -2 irradiated graphene showed minimal disorder with only a 6% increase in ID/IG compared to pre-irradiated graphene. These results support the use of graphene-enhanced GaN UV photodetectors in radiation-rich environments such as deep space.

Authors:
 [1];  [2];  [1];  [1];  [3];  [1]
  1. Stanford Univ., CA (United States)
  2. Hanyang Univ., Seoul (Korea, Republic of)
  3. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE Office of Science (SC). Basic Energy Sciences (BES) (SC-22); USDOE
OSTI Identifier:
1425766
Alternate Identifier(s):
OSTI ID: 1412615
Report Number(s):
LA-UR-17-30470
Journal ID: ISSN 0003-6951
Grant/Contract Number:
AC52-06NA25396
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Applied Physics Letters
Additional Journal Information:
Journal Volume: 111; Journal Issue: 24; Journal ID: ISSN 0003-6951
Publisher:
American Institute of Physics (AIP)
Country of Publication:
United States
Language:
English
Subject:
47 OTHER INSTRUMENTATION; Material Science

Citation Formats

Miller, Ruth A., So, Hongyun, Chiamori, Heather C., Dowling, Karen M., Wang, Yongqiang, and Senesky, Debbie G.. Graphene-enhanced gallium nitride ultraviolet photodetectors under 2 MeV proton irradiation. United States: N. p., 2017. Web. doi:10.1063/1.5005797.
Miller, Ruth A., So, Hongyun, Chiamori, Heather C., Dowling, Karen M., Wang, Yongqiang, & Senesky, Debbie G.. Graphene-enhanced gallium nitride ultraviolet photodetectors under 2 MeV proton irradiation. United States. doi:10.1063/1.5005797.
Miller, Ruth A., So, Hongyun, Chiamori, Heather C., Dowling, Karen M., Wang, Yongqiang, and Senesky, Debbie G.. Mon . "Graphene-enhanced gallium nitride ultraviolet photodetectors under 2 MeV proton irradiation". United States. doi:10.1063/1.5005797.
@article{osti_1425766,
title = {Graphene-enhanced gallium nitride ultraviolet photodetectors under 2 MeV proton irradiation},
author = {Miller, Ruth A. and So, Hongyun and Chiamori, Heather C. and Dowling, Karen M. and Wang, Yongqiang and Senesky, Debbie G.},
abstractNote = {The electrical characteristics of gallium nitride (GaN) ultraviolet (UV) photodetectors with graphene and semitransparent Ni/Au electrodes subjected to 2 MeV proton irradiation are reported and compared. Graphene is shown to have a very high transmittance (87%) in the UV regime (365 nm) compared to semitransparent Ni/Au (3 nm / 10 nm) films (32%). Correspondingly, microfabricated graphene/GaN photodetectors showed a much higher pre-irradiation responsivity of 3388 A/W while that of semitransparent Ni/Au/GaN photodetectors was 351 A/W. For both types of electrodes, intermittent current-voltage measurements made during 2 MeV proton irradiation showed minimal variation up to a fluence of approximately 3.8 × 1013 cm-2. Additionally, Raman spectroscopy of 200 keV proton beam, 3.8 × 1013 cm-2 irradiated graphene showed minimal disorder with only a 6% increase in ID/IG compared to pre-irradiated graphene. These results support the use of graphene-enhanced GaN UV photodetectors in radiation-rich environments such as deep space.},
doi = {10.1063/1.5005797},
journal = {Applied Physics Letters},
number = 24,
volume = 111,
place = {United States},
year = {Mon Dec 11 00:00:00 EST 2017},
month = {Mon Dec 11 00:00:00 EST 2017}
}

Journal Article:
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