Dresden 2017 – wissenschaftliches Programm
DS 21.7: Vortrag
Dienstag, 21. März 2017, 11:00–11:15, CHE 91
Analysis of surface oxidation of TiON ALD films — Justyna Łobaza, •Małgorzata Kot, and Dieter Schmeißer — BTU Cottbus-Senftenberg, Konrad-Wachsmann-Allee 17, 03046 Cottbus
Titanium oxynitride (TiON) films are interesting due to their remarkable optical and electronic properties which strongly depend on the O/N ratio. However, it is known that films containing Ti are prone to oxidation in contact with the air . In this work, we study the thickness of a surface oxidation layer which is inherently formed on the atomic layer deposition (ALD) grown TiON/TiN films on Si substrate. We use an Ar+ ion bombardment source and X-ray photoelectron spectroscopy (XPS) for this analysis. We calibrate the sputter rate by using substrate signal intensity decay (here Si 2p) in the XPS spectra of the 5 nm thick TiON sample accordingly. This rate is assumed to be constant when films with a larger thickness are analyzed. We find that the surface oxidation layer is about 1 nm thick, independent on the detailed ALD parameters of the films. The TiN films found underneath are close to the stoichiometric values and have a residual O content below 5%. Finally, we compare these data to our previous results collected with synchrotron-based radiation source [2,3].
References:  Sowinska et al., Applied Physics Letters 100, 233509 (2012).  M. Sowinska et al., Applied Surface Science 381, 42-47 (2016).  M. Sowińska et al., Journal of Vacuum Science and Technology A, 01A12734 (2016).