Dependence of Intrinsic Defects in ZnO Films on Oxygen Fraction Studied by Positron Annihilation
PENG Cheng-Xiao1, WENG Hui-Min1, YANG Xiao-Jie2, YE Bang-Jiao1, CHENG Bin1, ZHOU Xian-Yi1, HAN Rong-Dian1
1Department of Modern Physics, University of Science and Technology of China, Hefei 230026
2Key Laboratory of Nano-Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083
Dependence of Intrinsic Defects in ZnO Films on Oxygen Fraction Studied by Positron Annihilation
1Department of Modern Physics, University of Science and Technology of China, Hefei 230026
2Key Laboratory of Nano-Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083
Abstract： Defects in ZnO films grown by radio-frequency reactive magnetron sputtering under variable ratios between oxygen and argon gas have been investigated by using the monoenergetic positron beam technique. The dominate intrinsic defects in these ZnO samples are O vacancies (V0) and Zn interstitials (Zni) when the oxygen fraction in the O2/Ar feed gas does not exceed 70% in the processing chamber. On the other hand, zinc vacancies are preponderant in the ZnO films fabricated in richer oxygen environment. The concentration of zinc vacancies increases with the increasing O2 fraction. For the oxygen fraction 85%, the number of zinc vacancies that could trap positrons will be smaller. It is speculated that some unknown defects could shield zinc vacancies. The concentration of zinc vacancies in the ZnO films varies with the oxygen fraction in the growth chamber, which is in agreement with the results of photoluminescence spectra.
(Defects and impurities: doping, implantation, distribution, concentration, etc.)
引用本文:
PENG Cheng-Xiao;WENG Hui-Min;YANG Xiao-Jie;YE Bang-Jiao;CHENG Bin;ZHOU Xian-Yi;HAN Rong-Dian. Dependence of Intrinsic Defects in ZnO Films on Oxygen Fraction Studied by Positron Annihilation[J]. 中国物理快报, 2006, 23(2): 489-492.
PENG Cheng-Xiao, WENG Hui-Min, YANG Xiao-Jie, YE Bang-Jiao, CHENG Bin, ZHOU Xian-Yi, HAN Rong-Dian. Dependence of Intrinsic Defects in ZnO Films on Oxygen Fraction Studied by Positron Annihilation. Chin. Phys. Lett., 2006, 23(2): 489-492.
2006, Vol. 23 
