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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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Photoluminescence from GaN Implanted with Be and F
GaN samples are implanted with Be and F and annealed in different conditions to activate the BeGaacceptors. Photoluminescence spectra are studied to recognize the defects. The UVLBeband with a maximum at 3.38 eV and the YLBeband with a maximum at 2.15 eV are observed and associated with Be. The sequential implantation of Be and F ions into GaN at 600 °C reduces the concentration of nitrogen vacancies (VN), as evidenced by the lack of the green luminescence band associated with the isolated nitrogen vacancy. First‐principles calculations are employed to find parameters of defects that can form after implantation.
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- Award ID(s):
- 1904861
- PAR ID:
- 10415893
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- physica status solidi (b)
- Volume:
- 260
- Issue:
- 9
- ISSN:
- 0370-1972
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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