Microvoid formation in hydrogen-implanted ZnO probed by a slow positron beam

Journal Article · Tue Mar 15 00:00:00 EST 2005 · Physical Review. B, Condensed Matter and Materials Physics

DOI:https://doi.org/10.1103/PhysRevB.71.115213· OSTI ID:20666254

Chen, Z Q; Kawasuso, A; Xu, Y; Naramoto, H; Yuan, X L; Sekiguchi, T; Suzuki, R; Ohdaira, T ^[1]

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1. Advanced Science Research Center, Japan Atomic Energy Research Institute, 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan)

ZnO crystals were implanted with 20-80 keV hydrogen ions up to a total dose of 4.4x10{sup 15} cm{sup -2}. Positron lifetime and Doppler broadening of annihilation radiation measurements show introduction of zinc vacancy-related defects after implantation. These vacancies are found to be filled with hydrogen atoms. After isochronal annealing at 200-500 deg. C, the vacancies agglomerate into hydrogen bubbles. Further annealing at 600-700 deg. C causes release of hydrogen out of the bubbles, leaving a large amount of microvoids. These microvoids are annealed out at high temperature of 1000 deg. C. Raman spectroscopy for the implanted sample shows the enhancement of vibration modes at about 575 cm{sup -1}, which indicates introduction of oxygen vacancies. These oxygen vacancies disappear at temperatures of 600-700 deg. C, which is supposed to contribute to the hydrogen bubble formation. Cathodoluminescence measurements reveal that hydrogen ions also passivate deep level emission centers before their release from the sample, leading to the improvement of the UV emission.

• OSTI ID: 20666254
• Journal Information: Physical Review. B, Condensed Matter and Materials Physics, Vol. 71, Issue 11; Other Information: DOI: 10.1103/PhysRevB.71.115213; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 1098-0121
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ANNEALING
ANNIHILATION
CATHODOLUMINESCENCE
CRYSTALS
DEFECTS
DOPPLER BROADENING
HYDROGEN
HYDROGEN IONS
ION IMPLANTATION
KEV RANGE 10-100
OSCILLATION MODES
POSITRON BEAMS
POSITRONS
RADIATION DOSES
RAMAN SPECTRA
RAMAN SPECTROSCOPY
SEMICONDUCTOR MATERIALS
TEMPERATURE RANGE 0400-1000 K
TEMPERATURE RANGE 1000-4000 K
VACANCIES
VOIDS
ZINC OXIDES