Surface structure scattering

NSOM Near-Held scanning optical microscopy [103a] Light from a sharp tip scatters off sample Surface structure to 3 nm... 

SIAM Scanning interferometric apertureless microscopy [103b] Laser light is reflected off the substrate, and scattering between an AFM tip and sample is processed interferometrically Diffraction Surface structure... 

HEED High-energy electron diffraction [104] Diffraction of elastically back-scattered electrons (-20 keV, grazing incidence) Surface structure... 

B1.23 Surface structural determination particle scattering methods... 

The major role of TOF-SARS and SARIS is as surface structure analysis teclmiques which are capable of probing the positions of all elements with an accuracy of <0.1 A. They are sensitive to short-range order, i.e. individual interatomic spacings that are <10 A. They provide a direct measure of the interatomic distances in the first and subsurface layers and a measure of surface periodicity in real space. One of its most important applications is the direct determination of hydrogen adsorption sites by recoiling spectrometry [12, 4T ]. Most other surface structure teclmiques do not detect hydrogen, with the possible exception of He atom scattering and vibrational spectroscopy. 

Marchut L, Buck T M, Wheatley G H and McMahon C J Jr 1984 Surface structure analysis using low energy ion scattering Surf. Sc/. 141 549-66... 

Aono M, Katayama M and Nomura E 1992 Exploring surface structures by coaxial impact collision ion scattering spectroscopy (CAICISS) Nucl. Instrum. Methods B 64 29-37... 

Kim C, Hefner C and Rabalais J W 1997 Surface structure determination from ion scattering images Surf. Sc/. 388 LI 085-91... 

Tidsweii i M, Lucas C A, Markovic N M and Ross P N 1995 Surface structure determination using anomaious x-ray scattering Underpotentiai deposition of copper on Pt(111) Phys. Rev. B 51 10 205-8... 

Table 5. Diffraction and Scattering Methods for Surface Structure and Composition ...

Parameters measured Surface topography (rms roughness, rms slope, and power spectrum of structure) scattered light line shape of periodic structure (width, side wall angle, height, and period)... 

RHEED is a powerful tool for studying the surface structure of crystalline samples in vacuum. Information on the surface symmetry, atomic-row spacing, and evidence of surfece roughness are contained in the RHEED pattern. The appearance of the RHEED pattern can be understood qualitatively using simple kinematic scattering theory. When used in concert with MBE, a great deal of information on film growth can be obtained. 

The surface structures of ionic liquids have been studied by direct recoil spectrometry. In this experiment, a pulsed beam of 2-3 keV inert gas ions is scattered from a liquid surface, and the energies and intensities of the scattered and sputtered (recoiled) ions are measured as a function of the incident angle, a, of the ions. Figure 4.1-16 shows a scheme of the process for both the scattered and sputtered ions. 

Kuntze J, Speller S, Heiland W, Atrei A, Rovida G, Bardi U. 1999. Surface structure and composition of the alloy Au3Pd(100) determined by LEED and ion scattering spectroscopy. Phys Rev B 60 1535-1538. 

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