AVS 50th International Symposium
    Applied Surface Science Wednesday Sessions
       Session AS-WeM

Paper AS-WeM7
Determination of ToF Medium Energy Backscattering Capabilities for Interfacial Analysis

Wednesday, November 5, 2003, 10:20 am, Room 324/325

Session: High-K Materials Interface Analysis
Presenter: R.D. Geil, Vanderbilt University
Authors: R.D. Geil, Vanderbilt University
B.R. Rogers, Vanderbilt University
D.W. Crunkleton, Vanderbilt University
Z. Song, Vanderbilt University
R.A. Weller, Vanderbilt University
Correspondent: Click to Email
Time-of-flight medium energy backscattering (ToF-MEBS) is a unique surface analysis technique developed at Vanderbilt initially for determining levels of transition metal contaminants on silicon surfaces. The technique's high sensitivity and depth resolution makes it highly suitable for the analysis of ultra-thin films, such as gate dielectrics. The interface between the gate dielectric and silicon is of particular interest because it is a dominant factor in determining the overall electrical properties of the gate structure.@footnote 1@ In order to determine the extent of information about the lower interface region of a gate dielectric that ToF-MEBS can provide, we have studied a well-characterized material system, SiO@sub 2@/Si. Thermally grown SiO@sub 2@ films with thicknesses ranging from 2-10 nm were analyzed to determine how interfacial information degrades with depth into the sample. Thickness and stoichiometric information at the bulk and interfacial regions were determined. Channeling in the <100> direction of the Si substrate was performed to suppress background. TEM analysis was performed on the films to confirm ToF-MEBS thickness values. Spectroscopic ellipsometry was also used for thickness comparisons. XPS analysis provided extra interfacial and compositional information. @FootnoteText@ @footnote 1@ Wilk, G.D., R.M. Wallace, and J.M. Anthony, High-K Gate Dielectrics: Current Status and Materials Properties Considerations. Applied Physics Review, 2001. 89(10): p. 5243-5275.