IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Applied Surface Analysis Monday Sessions
       Session AS-MoP

Paper AS-MoP3
Determination of In-Depth Profiles Using Deconvolution of Angle Dependent XPS: Model Systems and Copolymer Surface Compositions

Monday, October 29, 2001, 5:30 pm, Room 134/135

Session: Student Poster Competition/Aspects of Applied Surface Analysis I Poster Session
Presenter: C.M. Mahoney, State University of New York at Buffalo
Authors: C.M. Mahoney, State University of New York at Buffalo
J. Elman, Eastman Kodak
J.A. Gardella, Jr., State University of New York at Buffalo
Correspondent: Click to Email
The depth information obtained by angle dependent XPS is not a direct measure of the composition as a function of depth. All atoms within the path of the probing X-ray will contribute to the signal, but the contribution of each will decrease exponentially with distance from the free surface. The spectra obtained are convoluted in a manner which will be more representative of the very surface, rather than deeper into the bulk. Here we test a numerical algorithm with defined boundary conditions based on polymer compositions. Unlike previous algorithms, this method was designed for samples with compositional gradients, as is common with many copolymer systems. Previously we have reported this method in studying copolymer surfaces including poly(amideurethane), Dimethylsiloxane-Urea-Urethane, and Poly(imidesiloxane) block copolymers. However, most of this work has described the relative compositions between various polymers. It is of interest to determine the accuracy of this algorithm in determining overlayer thicknesses and concentration depth profiles. The accuracy was determined through comparison of the calculated values to model systems based on polymer chain configurations. It has been determined that this method is accurate in the approximation of overlayer thicknesses in copolymer systems. The accuracy of this technique will be further examined through measurement of a reference material containing a thin layer (20-30Å) of poly(methylmethacrylate) (PMMA) deposited on Si containing its native oxide.