AVS 50th International Symposium
    Applied Surface Science Thursday Sessions
       Session AS-ThA

Paper AS-ThA9
Spectroscopic Ellispometry Analysis of Chemical Vapor Deposited Zirconia Thin Films

Thursday, November 6, 2003, 4:40 pm, Room 324/325

Session: Electron and Photon Spectroscopies
Presenter: B.R. Rogers, Vanderbilt University
Authors: B.R. Rogers, Vanderbilt University
Z. Song, Vanderbilt University
R.D. Geil, Vanderbilt University
D.W. Crunkleton, Vanderbilt University
Correspondent: Click to Email
The integration of high-k dielectric materials into MOSFET fabrication processes will require a non-destructive, fast, and accurate method for film characterization and process control. Spectroscopic ellipsometry (SE) is an outstanding candidate for these applications. This study reports the results of a multi-sample, variable-angle SE (VASE) analysis to characterize zirconia thin films deposited on Si(100) by high vacuum chemical vapor deposition (HVCVD). We evaluated several optical models of the samples to determine which best described the experimental data. A two-layer model consisting of a Tauc-Lorentz layer on the top of a Lorentz interfacial layer resulted in the best fit. This model was used to extract the optical constants of both the zirconia and the interfacial layers. The extracted optical constants were then used as constants in additional models to optimize the analyses. Most of the models fit the data below 6.0 eV extremely well. However, significant differences in goodness of fit were seen between the models'predictions above 6.0 eV photon energies. We feel these differences are due to an increased sensitivity to the interfacial layers for photons above 6.0 eV. The influence of the quality of interfacial layers on the accuracy of extracted optical constants will be discussed. Supporting data from XPS, TEM, and time-of-flight medium energy backscattering analyses will also be presented.