| As a sort of optic-electrical information materials, transparent conductive oxide take up an extremely position. It can be widely used in many fields such as light-emitting device (LED, LD), solar cells, ultraviolet detectors, sensors, surface acoustic wave devices, flat panel liquid crystal displays, transparent electrodes and received extensive attention. Zinc oxide (ZnO) is a II-VI oxides with wide bandgap,which is n-type semiconductor material with hexagonal crystal structure. Defects and were easy to dope in ZnO, Compared to tin oxide (ITO) and SnO2, the abundant raw materials, low cost, relatively low deposition temperature and stability in hydrogen plasma environment are all the advantages it has, Ga doped ZnO films (GZO) have excellent optical properties comparable to the ITO thin films (high visible light transmittance and low resistivity), which has become one of the hot area of research.The surface morphology and structural properties were studied by XRD, SEM, AFM, UV-visible, spectrophotometer was used to detect transmission, reflectance and other optical properties of film in all the spectral region.Van der Pauw method was applied to measure the electrical properties and analyze the conduction mechanism of thin films. This paper also studied the thermal characteristics and the magnetoresistive characteristics of GZOthin film. Through experiments and analysis, the following conclusions were shown as follows:1. GZO films are polycrystalline with hexagonal structure and (002) preferred orientation. The grain size is 10 ~ 30nm. the appropriate amount of Ga doping concentration and substrate temperature can improve the crystalline quality, increase the grain size and make the surface of films more dense.2. XPS analysis shows that: Zn and Ga elements existed in Zn2+ and Ga3+ form, respectively. No other valence can be found. The Ga content of the films is higher than the target.3. Thickness, doping concentration, and substrate temperature have greater impacts on the resistivity of the GZO films, increasing the thickness, appropriate amount of doping concentration, substrate temperature can obtain a high conductivity.4. The average visible light transmittance of thin film samples were above 80%, with the doping concentration increased, the optical absorption edge shifted to the shortwave, which is called "blue shift". Heavily doped level would lead to emergence of "red-shift".5. GZO film has strong thermal effect, the EMF of GZO film is negative, indicating that GZO film is n-type conductor; as the film thickness increases, Seebeck coefficient increases; 1at.% Ga-doped sample has the maximum absolute value of Seebcek coefficient for 74.77μV / K.6. GZO film has strong magnetoresistance. The reluctance increased with the increases of magnetic field strength and Hall mobility. When the magnetic field strength of 2.15T, the maximum reluctance was 0.77%, which can be obtained for the 3at% Ga doped GZO films.7. Take optical, electrical properties into consideration, the optimum conditions for the preparation of GZO film are: Doping concentration of 3at.%, working pressure of 2Pa, power of 160W, target distance of 7cm, on the Substrate temperature of 300℃. The lowest resistivity is 1.44×10-3?.cm, the average light transmission rate is beyond 80%, met the performance requirements of transparent conductive film.The sample with doping concentration of 1at.% has the highest thermoelectric power of 74.77.μV / K.
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