Quantitative XPS depth profiling for nickel/4H‐SiC contact with layered structure

Argon ion etching is used as the precleaning procedure on 4H‐SiC wafer prior to Ni deposition by means of physical vapor deposition (PVD). The thin film Ni/SiC sample is then vacuum annealed at 800 °C for 20 min. The results of XPS depth profiling show that a layered structure of C and Ni 2 Si forms during the heat treatment. When depth profiling, preferential etching of Si in Ni 2 Si occurs, the effect of which decreases as ion beam energy increases. Low energy argon ions reduce the atomic mixing. The etch rates of the Ni 2 Si and C‐rich layers are estimated from the shift of Ni profiles obtained by measuring the Ni 2p 3/2 and Ni 3p intensities. At the end, the measured depth profile is reconstructed after correcting for the influence of the electron attenuation length. Copyright © 2006 John Wiley & Sons, Ltd.