Chin. Phys. B ›› 2012, Vol. 21 ›› Issue (12): 127901-127901.doi: 10.1088/1674-1056/21/12/127901

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

Charging dynamics of polymer due to electron irradiation: A simultaneous scattering-transport model and preliminary results

曹猛, 王芳, 刘婧, 张海波   

  1. Key Laboratory for Physical Electronics and Devices of the Ministry of Education, Department of Electronic Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China
  • 收稿日期:2012-04-27 修回日期:2012-05-17 出版日期:2012-11-01 发布日期:2012-11-01
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant No. 11175140) and the Fundamental Research Funds for the Central Universities.

Charging dynamics of polymer due to electron irradiation: A simultaneous scattering-transport model and preliminary results

Cao Meng (曹猛), Wang Fang (王芳), Liu Jing (刘婧), Zhang Hai-Bo (张海波)   

  1. Key Laboratory for Physical Electronics and Devices of the Ministry of Education, Department of Electronic Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China
  • Received:2012-04-27 Revised:2012-05-17 Online:2012-11-01 Published:2012-11-01
  • Contact: Zhang Hai-Bo E-mail:hbzhang@mail.xjtu.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant No. 11175140) and the Fundamental Research Funds for the Central Universities.

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摘要： We present a novel numerical model and simulate preliminarily the charging process of polymer subjected to electron irradiation of several 10 keV. The model includes the simultaneous processes of electron scattering and ambipolar transport and the influence of a self-consistent electric field on the scattering distribution of electrons. The dynamic spatial distribution of charges is obtained and validated by existing experimental data. Our simulations show that excess negative charges are concentrated near the edge of the electron range. However, the formed region of high charge density may extend to the surface and bottom of a kapton sample, due to the effects of electric field on electron scattering and charge transport, respectively. Charge trapping is then demonstrated to significantly influence the charge motion. The charge distribution can be extended to the bottom as the trap density decreases. Charge accumulation is therefore balanced by the appearance and increase of leakage current. Accordingly, our model and numerical simulation provide a comprehensive insight into the charging dynamics of polymer irradiated by electrons in the complex space environment.

关键词: electron irradiation, charging dynamics, electron scattering, charge transport, polymer

Abstract: We present a novel numerical model and simulate preliminarily the charging process of polymer subjected to electron irradiation of several 10 keV. The model includes the simultaneous processes of electron scattering and ambipolar transport and the influence of a self-consistent electric field on the scattering distribution of electrons. The dynamic spatial distribution of charges is obtained and validated by existing experimental data. Our simulations show that excess negative charges are concentrated near the edge of the electron range. However, the formed region of high charge density may extend to the surface and bottom of a kapton sample, due to the effects of electric field on electron scattering and charge transport, respectively. Charge trapping is then demonstrated to significantly influence the charge motion. The charge distribution can be extended to the bottom as the trap density decreases. Charge accumulation is therefore balanced by the appearance and increase of leakage current. Accordingly, our model and numerical simulation provide a comprehensive insight into the charging dynamics of polymer irradiated by electrons in the complex space environment.

Key words: electron irradiation, charging dynamics, electron scattering, charge transport, polymer

中图分类号:  (Theory of impact phenomena; numerical simulation)

  • 79.20.Ap
72.20.Jv (Charge carriers: generation, recombination, lifetime, and trapping) 02.70.Uu (Applications of Monte Carlo methods)