Performance of Si-based solar cell utilizing optimized Al-doped ZnO films as TCO layer

Aluminum-doped zinc oxide (AZO) is one of the most popular transparent conducting oxide layers that can be employed in many optoelectronic applications in particular in photovoltaic devices due to being a low-cost and nontoxic material. In this study, we report on the effect of deposition pressure and substrate temperature on the properties of AZO films and solar cell performance by employing the optimized films. This study consists of two stages, the first of which concerns the optimization deposition pressure while the second is the substrate temperature of AZO films by evaluating the structural, optical, and electrical properties of the films. The deposited AZO thin film under 10 mTorr deposition pressure exhibited high optical transmission (89.9%), low electrical resistivity (9.1 × 10 −2 Ω.cm), and high carrier concentration (3.74 × 10 19 cm −3 ) among the others. The impact of substrate temperature was then investigated using this deposition pressure at room temperature, 150, 200, and 250 °C. The deposited AZO films at 150 °C temperature were found to possess the highest optical transmission (91.1%), lowest resistivity (9.9 × 10 −4 Ω.cm), and highest carrier concentration (1.1 × 10 20 cm −3 ) values. Hence, the 10 mTorr deposition pressure and 150 °C substrate temperature were selected as the optimum growth parameters to obtain AZO films, which were then employed in the cell structure. It was, thus, revealed that utilizing AZO films in silicon-based solar cell using such parameters led to the enhancement in the cell efficiency.