Effect of Cu/Al ratio on the properties of CuAlSe2 thin films prepared by co-evaporation

被引:13
作者
Reddy, Y. Bharath Kumar [1 ]
Raja, V. Sundara [1 ]
机构
[1] Sri Venkateswara Univ, Dept Phys, Solar Energy Lab, Tirupati 517502, Andhra Pradesh, India
关键词
compound semiconductors; optical properties; structural properties; electrical properties;
D O I
10.1016/j.matchemphys.2005.12.025
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
Cu-rich, near-stoichiometric and Al-rich CuAlSe2 thin films were deposited by elemental co-evaporation technique on glass substrates held at 673 K. Powder X-ray diffraction studies revealed that the Cu-rich CuAlSe2 films contain CU2Se as second phase while near-stoichiometric and Al-rich CuAlSe2 films are single phase. The Cu-rich and near-stoichiometric films are found to have chalcopyrite structure and the Al-rich films have defect chalcopyrite structure due to formation of ordered vacancy compound CuAl2Se3.5. The optical band gaps of Cu-rich, near-stoichiometric and Al-rich films determined from optical absorption studies are found to be 2.48 eV, 2.62 eV and 2.87 eV respectively. The electrical conductivity studies revealed that the Cu-rich and stoichiometric films are p-type and Al-rich films are n-type conducting. The resistivity of the films is found to increase with decrease in Cu/Al ratio. (c) 2006 Elsevier B.V. All rights reserved.
引用
收藏
页码:152 / 157
页数:6
相关论文
共 32 条
  • [31] Defect physics of the CuInSe2 chalcopyrite semiconductor
    Zhang, SB
    Wei, SH
    Zunger, A
    Katayama-Yoshida, H
    [J]. PHYSICAL REVIEW B, 1998, 57 (16): : 9642 - 9656
  • [32] A phenomenological model for systematization and prediction of doping limits in II-VI and I-III-VI2 compounds
    Zhang, SB
    Wei, SH
    Zunger, A
    [J]. JOURNAL OF APPLIED PHYSICS, 1998, 83 (06) : 3192 - 3196