AVS 53rd International Symposium
    Applied Surface Science Tuesday Sessions
       Session AS+SS-TuM

Paper AS+SS-TuM13
Dynamical XPS Measurements

Tuesday, November 14, 2006, 12:00 pm, Room 2005

Session: Environmental Materials and X-ray Spectroscopies
Presenter: S. Suzer, Bilkent University, Turkey
Authors: A. Dana, Bilkent University, Turkey
S. Suzer, Bilkent University, Turkey
Correspondent: Click to Email
Photoelectron spectra of a clean silicon sample and another one containing 10 nm oxide layer are recorded while the sample rod is subjected to 10.0 V square pulses with varying frequencies in the range of 0.001 to 1000 Hz to probe the dynamical response of the samples. For the clean silicon sample the Si2p(Si0) peak is twinned and appears at correspondingly -10.0 eV and +10.0 eV binding energy positions (20.0 eV difference) at all frequencies measured. However, although the Si2p (Si4+) of the oxide is also twinned, the measured difference between the peaks is smaller than 20.0 eV and exhibits a strong frequency dependence due to charging of the oxide layer. The frequency dependence of the oxide layer can be experimentally simulated by the clean silicon tied through an external RC circuit. The frequency dependent shifts of the peaks, their broadening, and other related experimental parameters can be reproduced by modeling the various currents involved as a voltage controlled current source to yield a powerful extension of XPS for dynamical measurements of charging/discharging processes of surface structures. As a simple application of the technique we will show that the two O1s components, which can be assigned to SiOx and TiOy domains in a composite film, exhibit different dynamical behavior. Other applications fro probing dielectric properties of various surface structures will be presented and discussed.