| AVS 54th International Symposium | |
| Applied Surface Science | Monday Sessions |
| Session AS-MoM |
| Session: | Quantitative Surface Analysis I. Electron Spectroscopies: (Honoring the contributions of Martin Seah, NPL, and Cedric Powell, NIST) |
| Presenter: | C.J. Powell, National Institute of Standards and Technology |
| Correspondent: | Click to Email |
Auger electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS) have been productive tools for a large variety of scientific and technological purposes since commercial instruments became available almost 40 years ago. Elemental identification is relatively easy but quantitative measurements (e.g., identification of chemical state, determination of chemical composition, and measurement of film thicknesses) can be more difficult. I will give a brief overview of advances that have been made to calibrate instruments, assess surface sensitivity, and account for elastic scattering of the signal electrons. NIST databases are now available that provide XPS data, inelastic mean free paths, effective attenuation lengths (EALs), and elastic-scattering cross sections.1 A new NIST database for the Simulation of Electron Spectra for Surface Analysis (SESSA) was recently released.1 I will describe two applications of SESSA, one to assess the distinguishability of N composition profiles in SiON films on Si by angle-resolved XPS2 and the other to determine EALs for photoelectrons in SiO2.3 Small systematic differences between the SESSA results and experimental data give new insights into photoelectron excitation and transport. Finally, I will describe results from a VAMAS project to assess the magnitude of uncertainties in XPS peak intensities associated with different techniques and procedures for background subtraction.
1 http://www.nist.gov/srd/surface.htm.
2 C. J. Powell, W. S. M. Werner, and W. Smekal, Appl. Phys. Letters 89, 172101 (2006).
3 C. J. Powell, W. S. M. Werner, and W. Smekal, Appl. Phys. Letters 89, 252116 (2006).