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Title: Thermal annealing of GaN implanted with Be

GaN samples were implanted with Be and annealed in different conditions in order to activate the shallow BeGaacceptor. Low-temperature photoluminescence spectra were studied to find BeGa-related defects in the implanted samples. A yellow band with a maximum at about 2.2 eV (the YLBeband) was observed in nearly all samples protected with an AlN cap during the annealing and in samples annealed under ultrahigh N2pressure. A green band with a maximum at 2.35 eV (the GL2 band), attributed to the nitrogen vacancy, was the dominant defect-related luminescence band in GaN samples annealed without a protective AlN layer. The ultraviolet luminescence (UVLBe) band with a maximum at 3.38 eV attributed to the shallow BeGaacceptor with the ionization energy of 0.113 eV appeared in implanted samples only after annealing at high temperatures and ultrahigh N2pressure. This is the first observation of the UVLBeband in Be-implanted GaN, indicating successful activation of the BeGaacceptor.

 
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Award ID(s):
1904861
NSF-PAR ID:
10364159
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
American Institute of Physics
Date Published:
Journal Name:
Journal of Applied Physics
Volume:
131
Issue:
12
ISSN:
0021-8979
Page Range / eLocation ID:
Article No. 125704
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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