Characterization of Ti/TiN Films and SiO 2 /Ti Interfaces by Use of X-Ray Photoelectron Spectroscopy

The deposition and processing of thin films, such as barrier metals and anti-reflective coatings, can be enhanced using the information provided by various surface analysis techniques. We will show the application of x-ray photoelectron spectroscopy(XPS) to the production of Ti and TiN films suitable for use in ULSI CMOS integrated circuits. XPS can separate Ti and N photoelectron peaks and detect low (1.0-5.0 atomic%) contamination levels while providing surface and interface chemical state information. In this paper we will show that a) the effect of TiN deposition on subsequent Ti film quality from the same Ti target was determined to be minimal, b) the relation of anneal temperature to the extent of SiO 2 reduction by Ti metal was characterized on SiO 2 /Ti/TiN structures for temperatures from 600°C to 800°C, and c) the absorption of O into TiN films from ambient air was detected and confirmed.