Abstract
Positron lifetime and Doppler Broadening spectra have been measured for three types of GaAs semiconductors. Direct evidence of native vacancy-type defects is found in the semi-insulating (SI-type) and n-type sample as its average lifetime {ie45-1} andS-parameter are larger than the bulk value. No positron trapping occurred in p-type GaAs. The lifetime spectrum of n-GaAs has also been measured as a function of temperature. The increase in average lifetime {ie45-2} from 226 ps to 234 ps at the temperature range 95–330 K was observed and was explained by the ionization of the vacancy. The slight increase in bulk lifetime {ie45-3} with the temperature was caused by the lattice expansion and expansion coefficient α=14×10−6K−1 was evaluated.
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Chen Zhiquan: born in May 1969, Ph.D. graduate student. Current research interest is in positron annihilation.
Supported by the National Natural Science Foundation of China
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Zhiquan, C., Li, M., Shiqing, L. et al. Defect properties of GaAs by positron annihilation. Wuhan Univ. J. of Nat. Sci. 1, 45–48 (1996). https://doi.org/10.1007/BF02827578
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DOI: https://doi.org/10.1007/BF02827578