| Transparent conductive oxide (TCO) thin films is a wide-band oxide semiconductor, were widely applied in various opto-electronic devices, such as solar cell, flat panel display, gas sensor and low-emis glass. And ZnO is one of new material with wide development prospect. ZnO has been widely used in semiconductor and piezoelectric thin films because of its unique optical and electrical properties, moreover, it has been prepared by doping accounts for the good conductivity. Otherwise, for the superiority of ZnO such as raw materials easy availability, non-toxic, low cost and for the advantages of method simple, can adapt of different requirements.This paper studied the Sn-doped ZnO (ZnO:Sn) thin films and the Li-W co-doped ZnO (LWZO) films were prepared by the sol-gel method and radio frequency magnetron sputtering technology, respectively. And researched on the doping properties of ZnO-based transparent conductive films.The Sn-doped ZnO thin films were deposited onto quartz glass substrates by the sol-gel method. The effect of different technological parameters of preparation on the crystallinity, structural, optical and electrical properties of ZnO:Sn thin films were investigated. And the best preparation process was found:the prepared precursor solutions stirred at 60℃ for 3 h, the concentration of metal ions in ZnO:Sn sols was controlled at 0.8M and the molar ratio of Sn/Zn at 2 at.%. The aging time is 5 days. All films were coated onto silica glass using spin coating at s speed of 3500 rpm for 30s. These as-coated films were dried at 300"C for 10 min. After repeating the spin coating and drying procedures five times. Finally the films were annealed at 700℃ for 1h in the air ambiance. The ZnO:Sn films exhibited the best crystallization with a high-preferential c-axis orientation, showed an extremely smooth surface and grow crowded. The optical transmittance was greater than 90% and the lowest resistivity was 13.6 Ω·cm.The Li-W co-doped ZnO films growth were performed using radio frequency magnetron sputtering technology on quartz glass substrates. The ceramic target was sintered from ZnO (99.99% in purity), Li2O (99.99% in purity) and WO3 (99.99% in purity) at high temperature with the molar ratio of ZnO:Li2O:WO3=97.5:1.5:1. Ar as the sputtering gas. The LWZO thin films were deposited at different substrate temperature and at different sputtering pressure were studied by XRD, SEM, UV-VIS spectrophotometer, FTIR and four-point probe method respectively. The research showed that, the LWZO thin films were prepared under the process parameters of substrate temperature was 120℃, sputtering pressure was 1 Pa, sputtering power was 150 W, sputtering time was 60 min. The films achieved effective Li-W co-doping, showed columnar grain structure; the optical transmittance was greater than 84% as well as a clear Burstein-Moss shift effect in the ultraviolet was showed; the LWZO films exhibited high conductivity characteristic, about 10-3Ω.cm order of magnitude.In addition, this paper had researched H2 gas was introduced into the sputtering gas of Ar on the basis of the LWZO films were deposited by RF magnetron sputtering. The samples of LWZO:H thin films were obtained by changing the flow rates of H2gas. The result showed that the method of hydrogenated can improve the efficiency of the crystalline and surface morphology, and can also increase the transmittance, was 85%, and reduce the resistivity of the thin films, the lowest resistivity was 1.2×10-3 Ω·cm... |
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