Corrosion resistance analysis of aluminium-doped zinc oxide layers deposited by pulsed magnetron sputtering

• High quality Al-doped ZnO (AZO) films deposited by DC pulsed magnetron sputtering.
• EIS allows quantifying the durability of the AZO layers.
• Magnetron sputtering AZO layers show high corrosion resistance values of 10− 6 Ω.
• Correlation between corrosion resistance and optoelectronic properties is established.

In this paper an exhaustive analysis is performed on the electrochemical corrosion resistance of Al-doped ZnO (AZO) layers deposited on silicon wafers by a DC pulsed magnetron sputtering deposition technique to test layer durability. Pulse frequency of the sputtering source was varied and a detailed study of the electrochemical corrosion response of samples in the presence of a corrosive chloride media (NaCl 0.06 M) was carried out. Electrochemical impedance spectroscopy measurements were performed after reaching a stable value of the open circuit at 2 h, 192 h and 480 h intervals. Correlation of the corrosion resistance properties with the morphology, and the optical and electrical properties was tested. AZO layers with transmission values higher than 84% and resistivity of 6.54 × 10− 4 Ω cm for a deposition process pressure of 3 × 10− 1 Pa, a sputtering power of 2 kW, a pulse frequency of 100 kHz, with optimum corrosion resistance properties, were obtained.