About the key factors driving the resistivity of AuOx thin films grown by reactive magnetron sputtering

Deposition of gold containing oxygen thin films was carried out at room temperature onto silicon substrates by reactive magnetron sputtering under Ar/O2 plasma. Nuclear reaction analysis of films shows that different oxygen concentrations (AuOx with x = 0-1.2) can be reached depending on the growth conditions. X-ray diffraction and scanning electron microscopy of the deposited samples evidence nanocrystallised films formed of pure Au phase or of Au metal mixed to a low ordered Au2O3 phase. The films display a columnar growth with grains in the 20-30 nm size range. A higher resistivity than that of pure gold is systematically measured by a four probe method. The electrical resistivity of the films was found to be correlated to the mean oxygen amount, and also to the microstructure of the Au phase.