Studies of XPS Technique and Application in Thickness Measurement of Ultra-Thin Film

X-Ray Photoelectron Spectroscopy (XPS) analysis technique has been widely applied in semiconductor manufacturing and failure analysis. We used it for defects analysis and thin film characterization in wafer fabrication and for XPS valence state analysis of copper materials. XPS technique is also applied jointly with TOF-SIMS technique. In wafer fab, semiconductor & LED manufacturing, it is very challenging to measure the thickness of an ultra-thin film at nano meter range. In general, TEM is widely used for ultra-thin film physical measurement but usually its lateral dimension is limited. In this paper we will study X-Ray Photoelectron Spectroscopy analysis technique which employ a new analysis method by using angle resolved analysis technique. Furthermore, we have applied the new method in analysis of SiON film. It is achieved to measure an ultra-thin film at about 1.4nm. This method can be used for SiO2 thickness measurement, self-assembled thiol monolayer on Au and thickness of HfO2 on silicon substrate.