Pulsed laser annealing of Be-implanted GaN
Abstract
Postimplantation thermal processing of Be in molecular-beam-epitaxy-grown GaN by rapid thermal annealing (RTA) and pulsed laser annealing (PLA) was investigated. It has been found that the activation of Be dopants and the repair of implantation-induced defects in GaN films cannot be achieved efficiently by conventional RTA alone. On the other hand, good dopant activation and surface morphology and quality were obtained when the Be-implanted GaN film was annealed by PLA with a 248 nm KrF excimer laser. However, observations of off-resonant micro-Raman and high-resolution x-ray-diffraction spectra indicated that crystal defects and strain resulting from Be implantation were still existent after PLA, which probably degraded the carrier mobility and limited the activation efficiency to some extent. This can be attributed to the shallow penetration depth of the 248 nm laser in GaN, which only repaired the crystal defects in a thin near-surface layer, while the deeper defects were not annealed out well. This situation was significantly improved when the Be-implanted GaN was subjected to a combined process of PLA followed by RTA, which produced good activation of the dopants, good surface morphology, and repaired bulk and surface defects well.
- Authors:
-
- Centre for Optoelectronics, Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117576 (Singapore)
- Publication Date:
- OSTI Identifier:
- 20719672
- Resource Type:
- Journal Article
- Journal Name:
- Journal of Applied Physics
- Additional Journal Information:
- Journal Volume: 98; Journal Issue: 9; Other Information: DOI: 10.1063/1.2120893; (c) 2005 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0021-8979
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 36 MATERIALS SCIENCE; ANNEALING; BERYLLIUM IONS; CARRIER MOBILITY; CRYSTAL DEFECTS; DOPED MATERIALS; GALLIUM NITRIDES; ION IMPLANTATION; KRYPTON FLUORIDE LASERS; LAYERS; MOLECULAR BEAM EPITAXY; MORPHOLOGY; PENETRATION DEPTH; RAMAN SPECTRA; SEMICONDUCTOR MATERIALS; STRAINS; STRESSES; SURFACES; THIN FILMS; X-RAY DIFFRACTION
Citation Formats
Wang, H T, Tan, L S, and Chor, E F. Pulsed laser annealing of Be-implanted GaN. United States: N. p., 2005.
Web. doi:10.1063/1.2120893.
Wang, H T, Tan, L S, & Chor, E F. Pulsed laser annealing of Be-implanted GaN. United States. https://doi.org/10.1063/1.2120893
Wang, H T, Tan, L S, and Chor, E F. 2005.
"Pulsed laser annealing of Be-implanted GaN". United States. https://doi.org/10.1063/1.2120893.
@article{osti_20719672,
title = {Pulsed laser annealing of Be-implanted GaN},
author = {Wang, H T and Tan, L S and Chor, E F},
abstractNote = {Postimplantation thermal processing of Be in molecular-beam-epitaxy-grown GaN by rapid thermal annealing (RTA) and pulsed laser annealing (PLA) was investigated. It has been found that the activation of Be dopants and the repair of implantation-induced defects in GaN films cannot be achieved efficiently by conventional RTA alone. On the other hand, good dopant activation and surface morphology and quality were obtained when the Be-implanted GaN film was annealed by PLA with a 248 nm KrF excimer laser. However, observations of off-resonant micro-Raman and high-resolution x-ray-diffraction spectra indicated that crystal defects and strain resulting from Be implantation were still existent after PLA, which probably degraded the carrier mobility and limited the activation efficiency to some extent. This can be attributed to the shallow penetration depth of the 248 nm laser in GaN, which only repaired the crystal defects in a thin near-surface layer, while the deeper defects were not annealed out well. This situation was significantly improved when the Be-implanted GaN was subjected to a combined process of PLA followed by RTA, which produced good activation of the dopants, good surface morphology, and repaired bulk and surface defects well.},
doi = {10.1063/1.2120893},
url = {https://www.osti.gov/biblio/20719672},
journal = {Journal of Applied Physics},
issn = {0021-8979},
number = 9,
volume = 98,
place = {United States},
year = {Tue Nov 01 00:00:00 EST 2005},
month = {Tue Nov 01 00:00:00 EST 2005}
}