SONG Qiu-ming, LYU Ming-chang, TAN Xing etc. Influence of H/Al Co-doping on Eletrical and Optical Properties and Crystal Structure of ZnO-based Transparent Conducting Films[J]. Chinese Journal of Luminescence, 2014,35(4): 393-398
SONG Qiu-ming, LYU Ming-chang, TAN Xing etc. Influence of H/Al Co-doping on Eletrical and Optical Properties and Crystal Structure of ZnO-based Transparent Conducting Films[J]. Chinese Journal of Luminescence, 2014,35(4): 393-398 DOI: 10.3788/fgxb20143504.0393.
Influence of H/Al Co-doping on Eletrical and Optical Properties and Crystal Structure of ZnO-based Transparent Conducting Films
By incorporating suitable amount of H dopants and lowering the Al contents
the conflicts between low resistivity and high transmission in transparent conducting films have been successfully solved. The reduced resistivity of ZnO:Al films by hydrogen doping is attributed to the increased carrier density and carrier mobility. Hydrogen behaves as a shallow donor in ZnO and can provide plenty of electrons. Most importantly
it can increase the carrier mobility effectively by lowering the potential barrier between ZnO grains due to the passivation of O
-
defects around grain boundaries. The carrier mobility can also be increased due to the less impurity scattering induced by the lowering of Al dopants in ZnO films. With hydrogen doping
low resistivity (6.310
-4
cm) ZnO:Al samples with only 1/10 of Al contents compared to conventional AZO films can be got. The optical transmittance in near infrared region(1 200 nm) increases from 64% to 90% by comparing samples without and with H-doping is shown. This kind of high conductivity and high transmittance ZnO thin film will be excellent transparent conducting oxide candidate for various types of thin-film solar cells to improve the efficiency of the device.
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