Non-destructive characterization of thin silicides using X-ray reflectivity

Abstract

With the increasing miniaturisation, the use of thin silicide films in VLSI technology becomes more important X-ray reflectivity (XRR) is a non-destructive method for the characterization of layer thickness, surface and interfacial roughness of thin films. We have used XRR for the characterization of thin CoSi/sub 2/ and PtSi layers. The silicide films were prepared by rapid thermal annealing and XRR war used before and alter silicidation to measure the layer thickness. The XRR results are compared with results obtained on the same films by Rutherford backscattering spectrometry (RBS), cross-sectional transmission electron microscopy (XTEM), profilometry and atomic force microscopy (AFM). By XRR we were able to accurately measure the thickness of silicide layers down to 3 nm.