AVS 49th International Symposium
    Applied Surface Science Tuesday Sessions
       Session AS-TuP

Paper AS-TuP11
A Quantitative Comparison between Rutherford Backscattering and Time-of-Flight Medium Energy Backscattering

Tuesday, November 5, 2002, 5:30 pm, Room Exhibit Hall B2

Session: Topics in Applied Surface Science
Presenter: R.D. Geil, Vanderbilt University
Authors: B.R. Rogers, Vanderbilt University
R.D. Geil, Vanderbilt University
Z. Song, Vanderbilt University
D.W. Crunkelton, Vanderbilt University
R.A. Weller, Vanderbilt University
V. Pawar, Vanderbilt University
Correspondent: Click to Email
Both conventional Rutherford backscattering (RBS) and time-of-flight medium energy backscattering (ToF-MEBS) have been used to determine the thickness and stoichiometry of thin dielectric films (Al@sub 2@O@sub 3@) deposited on silicon, and a comparison is made between the two ion beam techniques. The characterization of these films is important in optimizing the deposition process and ultimately the film properties. The conventional RBS and ToF-MEBS systems are capable of 1.8 MeV and 270 keV He@super +@ beams, respectively. ToF-MEBS is a lower energy derivative of conventional RBS that offers improved depth resolution and sensitivity at the expense of total analyzable depth and ease of use.@footnote 1@ Channeling was performed with both systems to suppress the substrate signal and enhance the signal from the thin dielectric film. Grazing angle analysis was performed with the RBS system to increase particle path length in the sample, thereby improving depth resolution. It was found that for films less than about 200 Å RBS had little sensitivity to the thin Al@sub 2@O@sub 3@ films while ToF-MEBS detected Al and O in films that were tens of angstroms in thickness. @FootnoteText@ @footnote 1@ Weller, Robert A. Introduction to Medium-Energy Ion Beam Analysis. Methods in Materials Research (2000) 12b.1.