| Transparent conducting oxide (TCO) thin films used as electrode materials are widely applied in various optoelectronic devices and have attracted significant attention. Sn doped In2O3 (ITO) and Al-doped ZnO (AZO)films are the most common used TCO films due to their wide bandgap, high transparency and low resistivity. AZO film is particularly attractive because of its excellent properties, such as higher thermal stability, good resistance to hydrogen plasma, low cost and non-toxicity, campared to ITO.In order to obtain the optimal deposition conditions and high quality AZO films, we investigated the effects of doping sequences, concentration and deposition temperation on the structure, surface morphologies, electrical and optical properties of AZO films prepared by Atomic Layer Deposition. By changing different deposition condition, some points have been obtained.AZO films have been prepared with different doping sequences by ALD under certain temperature and doping concentration. The AZO films properties showed strong dependence on the doping sequence. With the optimized doping sequence of DEZ/TMA/H2O, the electrical resistivity of 8.5×10-4Ω?cm as well as the average optical transmittance in the visible light range of 92% could be achieved.By changing Al composition, we investigate the effect on the grain size, crystallinity and resistivity of AZO films. The results suggested that the Al composition is very important for the structure and properties of AZO films. The lowest resistivity of 8.5×10-4Ω?cm and the average optical transmittance in the visible light range of 93% was obtained with Zn cycle: Al cycle=14:1.Besides, by changing deposition temperature, we investigate the effect on the structure and resistivity of AZO films. With deposition temperature increasing, the growth orientation of AZO film changed from (100) orientation to (002) orientation. The lowest resistivity of AZO films was obtained with deposition temperature of 200°C. |
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