Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7903356 | Journal of Non-Crystalline Solids | 2013 | 5 Pages |
Abstract
Amorphous indium-gallium-zinc oxide (a-IGZO) thin films were deposited on quartz glass substrates via radio frequency magnetron sputtering. The effect of H2 annealing on the structural, electrical, and H-associated vibrational absorption properties of the a-IGZO films has been systematically studied. The temperature dependence of electrical conductivity of the as-grown and H2 annealed films showed n-type degenerated conduction behavior in the range of 10-300 K. Transport properties of these a-IGZO films do not fit well with variable range hopping model. Carrier mobility exhibited increased thermally-exited behavior as H2 annealing temperature is higher than 300 °C, suggesting existence of potential barriers above the mobility edge. Fourier Transform Infrared Spectroscopy illustrated OH vibrational mode absorption at around 3670 cmâ 1, suggesting the formation of OH bonding by H2 annealing process which increased at 250 °C then annealed away above 300 °C along with electron carriers in the a-IGZO films. Comparatively, this OH ir line was greatly mitigated in the a-IGZO films annealed in air. Decrease in electron concentration results from reduced OH absorption in the H2 annealed a-IGZO films upon annealing above 300 °C. Surface roughness of the a-IGZO films decreased with increasing H2 annealing temperature for the improvement of device interface uniformity.
Related Topics
Physical Sciences and Engineering
Materials Science
Ceramics and Composites
Authors
Yuanjie Li, Zilong Liu, Kai Jiang, Xiaofen Hu,