| Transparent conductive oxide (TCO) films have gotten widely attention due to its excellent photoelectric properties. In the present, ITO is the most commonly used TCO materials. But Indium is a toxic, rare and expensive element, thus zinc oxide (ZnO) or impurity-doped zinc oxide had been actively investigated as an alternative to ITO films. Unlike ITO, zinc oxide is a non-toxic, inexpensive and abundant material. ZnO can be doped with a wide variety of ions depending on the application fields to improve the properties, such as Al, Ga, In, B, Si, Ge, Ti, Zr and F. Among these dopants, ZnO doped aluminium (AZO) film is regarded as most suitable substitute for ITO film because of its thermal stability and relatively inexpensive cost.Unavoidably, the large lattice mismatch and great difference in the thermal expansion coefficients between AZO films and substrates would cause residual stress in the AZO films. In order to improve the crystalline quality of AZO films, the effective technique is thermal annealing treatment. Compared to conventional thermal furnace, rapid thermal furnace use halogen lamps as radiation heat, so the rate of heating and cooling is fast. Rapid thermal annealing (RTA) offers shorter cycle time, greatly reducing the probability of the sample exposing in the air. In view of the advantage of RTA, the study of the controlled details of the RTA parameters for improving the crystal quality of AZO films would be a subject of great interest.The same two groups of AZO films were prepared on glass substrate by DC magnetron sputtering. One group of AZO films were annealed at the temperature of 500℃, their annealing time is 30 s,60 s,90 s and 120 s, respectively; another group of AZO films were annealed for the time of 60 s, their annealing temperature is 300℃,500℃,550℃and 600℃, respectively. We carefully study the effects of annealing temperature and annealing time on the structural (such as morphology, stress and crystallization) and photoelectric characteristics of AZO films. The structural and photoelectric properties of AZO films were analyzed by means of X-ray diffraction, Atomic force microscope, Hall effect and UV-VIS spectrophotometer.Before RTA, for AZO film, the quality factor is 1.04×10-2Ω-1, and the surface roughness (Rrms) is 4.61 nm; the diffraction peak is located in 34.19°, corresponding to the grain size of 36.2 nm, and the surface stress of -2.95×109 N/m2. The photoelectric of AZO film has obtained, the resistivity is 9.90×10-4Ω·cm, corresponding carrier concentration of 6.23×1020 cm-3 and mobility of 10.03 cm2·v-1·s-1; the average transmittance is 83.2%, and the band gap of 3.70 eV is obtained from transmittance spetrum.After RTA, with the increase of annealing temperature and annealing time, the surface of AZO film is becoming smoother gradually; the diffraction peaks is closed to the standard peak diffraction peak of ZnO crystal (34.40°), besides this, the stress of AZO film is decreased, and the crystal grain is gradually grown; moreover, the photoelectric property of the film is further improved.For annealed AZO film, when the rapid thermal annealing temperature is 500℃and annealing time is 60s, the best quality factor of 8.41×10-2Ω-1 has been obtained. And its Rrms is 3.48 nm; the diffraction peak is located in 34.28°, corresponding the grain size is 43.4 nm, the surface stress is -1.71×109 N/m2; and its resistivity, carrier concentration and mobility are 3.47×10-4Ω·cm,1.23×1021 cm-3 and 14.67 cm2·v-1·s-1, respectively; the average transmittance is 92.3%, the band gap of 3.75 eV is calculated from transmittance spetrum.
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