This work addresses the role of excess Al and deposition rate in reducing the doping efficiency of Al +3 cations in Al-doped ZnO (AZO) films. In this regard, AZO films were deposited on the soda lime glass substrates using co-sputtering from ceramic AZO/ZnO and metallic Al targets. Whereas power to ZnO/AZO target was kept constant, power to Al target was varied to see the effect of varying Al concentration (and deposition rate) on its doping efficiency. Here, Al doping efficiency in ZnO is found to increase initially with increasing deposition rate and Al content, beyond which it decreased because of the formation of higher Al x O y in combination with increased trapped Al in the amorphous regions of these films. Moreover, a detailed discussion on the mechanism of the deposition rate and thereby induced variation in Al doping efficiency is discussed and then related to the optoelectronic properties of these films.

中文翻译：

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铝掺杂 ZnO 薄膜中铝的掺杂效率降低：过量铝和沉积速率的作用

这项工作解决了过量 Al 和沉积速率在降低 Al 掺杂 ZnO (AZO) 薄膜中 Al +3 阳离子的掺杂效率方面的作用。在这方面，AZO 薄膜使用陶瓷 AZO/ZnO 和金属铝靶的共溅射沉积在钠钙玻璃基板上。虽然 ZnO/AZO 靶的功率保持恒定，但改变 Al 靶的功率以观察不同的 Al 浓度（和沉积速率）对其掺杂效率的影响。在这里，发现 ZnO 中的 Al 掺杂效率最初随着沉积速率和 Al 含量的增加而增加，超过此值，由于形成更高的 Al x O y 以及这些薄膜的非晶区域中捕获的 Al 增加，因此它会降低。而且，