Narrow Results

This study investigated the effects of UV-ozone surface treatment on the electrical conduction and scattering mechanisms of gallium-doped zinc oxide (Ga: ZnO or GZO) thin films deposited on Corning glass substrates via radio-frequency sputtering at room temperature. Hall effect measurements at elevated temperatures revealed that grain boundary scattering dominated the electrical conduction in pristine GZO films, primarily due to their smaller grain sizes and weaker crystallinity. However, after a 70min UV-ozone treatment, the scattering mechanisms shifted to being dominated by lattice vibrations, which were attributed to significant grain growth and improved crystalline quality. Moreover, GZO films subjected to a 60min UV-ozone treatment exhibited several advantages, including enhanced crystallization, lower resistivity, and improved resistivity stability across a wide range of measurement temperatures. In addition to these electrical improvements, the surface properties of the treated films were also significantly enhanced. The 60min UV-ozone treatment led to increased surface energy and superior adhesion properties, which are critical for practical device applications. These findings highlight the potential of UV-ozone treatment as an effective technique to optimize both the electrical and surface characteristics of GZO thin films. Such enhancements make these films promising candidates for the fabrication of high-performance, high-stability electronic devices in various advanced applications.

Ga-doped ZnO (GZO)/metal/GZO structures were fabricated on glass substrates to be the transparent conducting layers in this study. GZO films and metal films were deposited at room-temperature by a radio-frequency sputter and a thermal evaporator, respectively. The GZO/Ag/GZO (GAG) structures had poor electrical and optical properties due to the formation of Ag islands on the GZO layer. A 1-nm Cu seed layer was deposited on the GZO layer to fabricate the GZO/Ag/Cu/GZO (GACG) structure to improve its electrical and optical properties. The GACG structure had sheet resistance of 9 $\mathrm{\Omega }$, average visible transmittance of 86% and figure of merit of $2.5\times 10^{-2}$${\mathrm{\Omega }}^{-1}$. In addition, the sheet resistance of the GACG structure kept almost the same after annealing at $300^{\circ }$C in atmosphere for more than 5 h, which showed good thermal stability.