中国物理B ›› 2018, Vol. 27 ›› Issue (8): 87401-087401.doi: 10.1088/1674-1056/27/8/087401

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

Characterization of ion irradiated silicon surfaces ablated by laser-induced breakdown spectroscopy

T Iqbal, M Abrar, M B Tahir, M Seemab, A Majid, S Rafique   

  1. 1 Department of Physics, Faculty of Sciences, University of Gujrat, Hafiz Hayat Campus, 50700, Gujrat, Pakistan;
    2 Department of Physics, Hazara University Mansehra, KP, 45300, Pakistan;
    3 Department of Physics, University of Engineering and Technology(UET), Lahore, Pakistan
  • 收稿日期:2018-01-30 修回日期:2018-05-23 出版日期:2018-08-05 发布日期:2018-08-05
  • 通讯作者: T Iqbal, M Abrar E-mail:tiqbal02@qub.ac.uk;mabrarphy@gmail.com

Characterization of ion irradiated silicon surfaces ablated by laser-induced breakdown spectroscopy

T Iqbal1, M Abrar2, M B Tahir1, M Seemab1, A Majid1, S Rafique3   

  1. 1 Department of Physics, Faculty of Sciences, University of Gujrat, Hafiz Hayat Campus, 50700, Gujrat, Pakistan;
    2 Department of Physics, Hazara University Mansehra, KP, 45300, Pakistan;
    3 Department of Physics, University of Engineering and Technology(UET), Lahore, Pakistan
  • Received:2018-01-30 Revised:2018-05-23 Online:2018-08-05 Published:2018-08-05
  • Contact: T Iqbal, M Abrar E-mail:tiqbal02@qub.ac.uk;mabrarphy@gmail.com

摘要: Low energy metallic ions, generated by a Q-switched Nd:YAG laser (1064-nm wavelength, 10-mJ energy, 9-nm~12-ns-pulse width, 1011 W/cm2 intensity) irradiated on a silicon substrate to modify various properties, such as electrical, morphological, and structural modifications. Thomson parabola technique is used to calculate the energy of these metallic ions whereas the electrical conductivity is calculated with the help of Four-point probe. Interestingly circular tracks forming chain like damage trails are produced via these energetic ions which are carefully examined by optical microscopy. It is observed that excitation, ionization, and cascade collisions are responsible for surface modifications of irradiated samples. Four-point probe analysis revealed that the electrical conductivity of substrate has reduced with increasing trend of atomic number of irradiated metallic ions (Al, Ti, Cu, and Au). The x-ray diffraction analysis elucidated the crystallographic changes leading to reduction of grain size of N-type silicon substrate, which is also associated with the metallic ions used. The decreasing trend of conductivity and grain size is due to thermal stresses, scattering effect, structural imperfections, and non-uniform conduction of energy absorbed by substrate atoms after the ion irradiation.

关键词: ablation, Thomson parabola technique, four-point probe

Abstract: Low energy metallic ions, generated by a Q-switched Nd:YAG laser (1064-nm wavelength, 10-mJ energy, 9-nm~12-ns-pulse width, 1011 W/cm2 intensity) irradiated on a silicon substrate to modify various properties, such as electrical, morphological, and structural modifications. Thomson parabola technique is used to calculate the energy of these metallic ions whereas the electrical conductivity is calculated with the help of Four-point probe. Interestingly circular tracks forming chain like damage trails are produced via these energetic ions which are carefully examined by optical microscopy. It is observed that excitation, ionization, and cascade collisions are responsible for surface modifications of irradiated samples. Four-point probe analysis revealed that the electrical conductivity of substrate has reduced with increasing trend of atomic number of irradiated metallic ions (Al, Ti, Cu, and Au). The x-ray diffraction analysis elucidated the crystallographic changes leading to reduction of grain size of N-type silicon substrate, which is also associated with the metallic ions used. The decreasing trend of conductivity and grain size is due to thermal stresses, scattering effect, structural imperfections, and non-uniform conduction of energy absorbed by substrate atoms after the ion irradiation.

Key words: ablation, Thomson parabola technique, four-point probe

中图分类号:  (Phonons)

  • 74.25.Kc
61.80.Ba (Ultraviolet, visible, and infrared radiation effects (including laser radiation)) 61.80.Lj (Atom and molecule irradiation effects) 61.82.-d (Radiation effects on specific materials)