Influence of surface excitations on electrons elastically backscattered from copper and silver surfaces

Journal Article · Thu Dec 15 04:00:00 EST 1994 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.50.17547· OSTI ID:6817441

Chen, Y F; Su, P; Kwei, C M ^[1]; Tung, C J ^[2]

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1. Department of Electronics Engineering, National Chiao Tung University, Hsinchu, Taiwan (Taiwan, Province of China)
2. Department of Nuclear Science, National Tsing Hua University, Hsinchu, Taiwan (Taiwan, Province of China)

The influence of surface excitations on electrons elastically backscattered from solid surfaces is investigated. Elastic-scattering differential cross sections are calculated using the partial-wave expansion method and the finite difference techique for solid atoms with the Hartree-Fock-Wigner-Seitz potential. An extended Drude dielectric function which allows the characteristic oscillator strength, damping constant, and critical-point energy for each subband of valence electrons is employed to estimate electron inelastic mean free paths for volume excitations. The same dielectric function is applied to evaluate the probability of surface excitations for incident and escape electrons by including the recoil effect without the small-angle approximation. Results of Monte Carlo simulations on the elastic reflection coefficient and the angular distribution of electrons elastically backscattered from Cu and Ag surfaces are presented. It is revealed that surface excitations significantly reduce the elastic reflection coefficient for low-energy electrons, but less significantly influence the angular distribution for large escape angles. Our results agree very well with experimental data.

• OSTI ID: 6817441
• Journal Information: Physical Review, B: Condensed Matter; (United States), Journal Name: Physical Review, B: Condensed Matter; (United States) Vol. 50:23; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

665300* -- Interactions Between Beams & Condensed Matter-- (1992-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
BACKSCATTERING
CALCULATION METHODS
COLLECTIVE EXCITATIONS
COLLISIONS
COMPUTERIZED SIMULATION
COPPER
CROSS SECTIONS
DIFFERENTIAL CROSS SECTIONS
ELASTIC SCATTERING
ELECTRON COLLISIONS
ELEMENTS
ENERGY-LEVEL TRANSITIONS
EXCITATION
FINITE DIFFERENCE METHOD
ITERATIVE METHODS
METALS
MONTE CARLO METHOD
NUMERICAL SOLUTION
PARTIAL WAVES
SCATTERING
SILVER
SIMULATION
SURFACES
TRANSITION ELEMENTS