Enhanced damage buildup in C+-implanted GaN film studied by a monoenergetic positron beam
2015
Wurtzite GaN films grown by hydride vapor phase epitaxy were implanted with 280 keV C+ ions to a dose of 6 × 1016 cm−2. Vacancy-type defects in C+-implanted GaN were probed using a slow positron beam. The increase of Doppler broadening S parameter to a high value of 1.08–1.09 after implantation indicates introduction of very large vacancy clusters. Post-implantation annealing at temperatures up to 800 °C makes these vacancy clusters to agglomerate into microvoids. The vacancy clusters or microvoids show high thermal stability, and they are only partially removed after annealing up to 1000 °C. The other measurements such as X-ray diffraction, Raman scattering and Photoluminescence all indicate severe damage and even disordered structure induced by C+-implantation. The disordered lattice shows a partial recovery after annealing above 800 °C. Amorphous regions are observed by high resolution transmission electron microscopy measurement, which directly confirms that amorphization is induced by C+-implantation...
Keywords:
- Amorphous solid
- Ion implantation
- Photoluminescence
- High-resolution transmission electron microscopy
- Wurtzite crystal structure
- Epitaxy
- Nuclear magnetic resonance
- Vacancy defect
- Doppler broadening
- Physics
- Annealing (metallurgy)
- Transmission electron microscopy
- Condensed matter physics
- Crystallography
- Raman spectroscopy
- Molecular physics
- Correction
- Source
- Cite
- Save
- Machine Reading By IdeaReader
37
References
12
Citations
NaN
KQI