中国物理B ›› 2018, Vol. 27 ›› Issue (4): 47103-047103.doi: 10.1088/1674-1056/27/4/047103

• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇    下一篇

Passivation of carbon dimer defects in amorphous SiO2/4H-SiC (0001) interface: A first-principles study

Yi-Jie Zhang(张轶杰), Zhi-Peng Yin(尹志鹏), Yan Su(苏艳), De-Jun Wang(王德君)   

  1. 1. Liaoning Integrated Circuit Technology Key Laboratory, School of Control Science and Engineering, Faculty of Electronic Information and Electrical Engineering, Dalian University of Technology, Dalian 116024, China;
    2. School of Physics, Dalian University of Technology, Dalian 116024, China
  • 收稿日期:2017-07-22 修回日期:2018-01-17 出版日期:2018-04-05 发布日期:2018-04-05
  • 通讯作者: De-Jun Wang E-mail:dwang121@dlut.edu.cn
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant No. 61474013).

Passivation of carbon dimer defects in amorphous SiO2/4H-SiC (0001) interface: A first-principles study

Yi-Jie Zhang(张轶杰)1, Zhi-Peng Yin(尹志鹏)1, Yan Su(苏艳)2, De-Jun Wang(王德君)1   

  1. 1. Liaoning Integrated Circuit Technology Key Laboratory, School of Control Science and Engineering, Faculty of Electronic Information and Electrical Engineering, Dalian University of Technology, Dalian 116024, China;
    2. School of Physics, Dalian University of Technology, Dalian 116024, China
  • Received:2017-07-22 Revised:2018-01-17 Online:2018-04-05 Published:2018-04-05
  • Contact: De-Jun Wang E-mail:dwang121@dlut.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant No. 61474013).

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摘要： An amorphous SiO2/4H-SiC (0001) interface model with carbon dimer defects is established based on density functional theory of the first-principle plane wave pseudopotential method. The structures of carbon dimer defects after passivation by H2 and NO molecules are established, and the interface states before and after passivation are calculated by the Heyd-Scuseria-Ernzerhof (HSE06) hybrid functional scheme. Calculation results indicate that H2 can be adsorbed on the O2-C=C-O2 defect and the carbon-carbon double bond is converted into a single bond. However, H2 cannot be adsorbed on the O2-(C=C)'-O2 defect. The NO molecules can be bonded by N and C atoms to transform the carbon-carbon double bonds, thereby passivating the two defects. This study shows that the mechanism for the passivation of SiO2/4H-SiC (0001) interface carbon dimer defects is to convert the carbon-carbon double bonds into carbon dimers. Moreover, some intermediate structures that can be introduced into the interface state in the band gap should be avoided.

关键词: 4H-SiC, interface defect, density of states, first principle

Abstract: An amorphous SiO2/4H-SiC (0001) interface model with carbon dimer defects is established based on density functional theory of the first-principle plane wave pseudopotential method. The structures of carbon dimer defects after passivation by H2 and NO molecules are established, and the interface states before and after passivation are calculated by the Heyd-Scuseria-Ernzerhof (HSE06) hybrid functional scheme. Calculation results indicate that H2 can be adsorbed on the O2-C=C-O2 defect and the carbon-carbon double bond is converted into a single bond. However, H2 cannot be adsorbed on the O2-(C=C)'-O2 defect. The NO molecules can be bonded by N and C atoms to transform the carbon-carbon double bonds, thereby passivating the two defects. This study shows that the mechanism for the passivation of SiO2/4H-SiC (0001) interface carbon dimer defects is to convert the carbon-carbon double bonds into carbon dimers. Moreover, some intermediate structures that can be introduced into the interface state in the band gap should be avoided.

Key words: 4H-SiC, interface defect, density of states, first principle

中图分类号:  (Semiconductor compounds)

  • 71.20.Nr
61.72.-y (Defects and impurities in crystals; microstructure) 71.20.-b (Electron density of states and band structure of crystalline solids)