AVS 52nd International Symposium
    Applied Surface Science Monday Sessions
       Session AS-MoA

Paper AS-MoA3
Evaluation of Electron Back-scattering in Auger Analysis using a Cross-sectioned GaAs/AlAs Superlattice

Monday, October 31, 2005, 2:40 pm, Room 206

Session: Electron Spectroscopies
Presenter: M. Suzuki, ULVAC-PHI, Inc., Japan
Authors: M. Suzuki, ULVAC-PHI, Inc., Japan
N. Urushihara, ULVAC-PHI, Inc., Japan
S. Iida, ULVAC-PHI, Inc., Japan
N. Sanada, ULVAC-PHI, Inc., Japan
D.F. Paul, Physical Electronics
J.S. Hammond, Physical Electronics
A. Yamamoto, ULVAC-PHI, Inc., Japan
Correspondent: Click to Email
It is generally well known that when using electron excitation analysis techniques such as Auger electron spectroscopy, the analyzed volume is expanded due to the scattering effects in a solid surface region. We will present experimental results to evaluate generation of Auger electrons by inelastic scattered electrons. A cleaved cross-section of a GaAs/AlAs superlattice, consisting of three different thicknesses of repeating layers of GaAs/AlAs (50 nm/50 nm, 20 nm/20 nm, and 10 nm/10 nm) was analyzed with a scanning Auger Nanoprobe. Along the analyzed line perpendicular to the 50 nm thick-layers, the kinetic energy of the Al KLL Auger electrons varied by 5 eV to 6 eV, with a spatial distribution corresponding with the GaAs/AlAs superlattice structure. The amplitude of the Auger peak energy shift with beam position was smaller for the 20 nm-thick layers and almost negligible for the 10 nm-thick layers. The highest and lowest Auger energy positions correspond to the AlAs and GaAs layers, respectively. The analyzed surface was covered with a naturally oxidized layer, as the cleavage was carried out in air. The lower Al kinetic energy signal was detected when the electron beam hit the AlAs region, due to the reduction of aluminum oxide caused by electron beam.@footnote1@ The higher Al kinetic energy signal associated with aluminum oxide was generated by inelastically scattered electrons when the beam was at the GaAs region. These results will be discussed based on a model of electron scattering. @FootnoteText@ @footnote1@ M. Arai et al., O-32, The third international symposium on practical surface analysis (PSA-03), Korea, October 2003.