GRAZING-INCIDENCE SMALL-ANGLE SCATTERING - MORPHOLOGY OF DEPOSITED CLUSTERS AND NANOSTRUCTURE OF THIN-FILMS

It is shown that grazing-incidence small-angle X-ray scattering (GISAX S) is a new experimental technique that combines both grazing incidenc e and scattering at low angles. The experiments are carried out at or near the critical angle: the result is a considerably enhanced surface sensitivity. It allows morphological characterization of aggregates d eposited or gathered on a flat substrate, such as silicon wafer or Com ing glass. The full potential of this technique is realized when using a synchrotron source (flux, collimation and choice of wavelength in o rder to avoid fluorescence or to perform anomalous measurements) and w hen patterns are recorded with two-dimensional detectors: gas detector s or imaging plates (IPs). It is then possible to study the anisotropi c shape of the scattering pattern and to determine the sizes of the ag gregates. Results are presented for gold clusters deposited on a silic on wafer covered by a carbon sublayer in order to make a comparison wi th transmission electron microscopy and with scanning probe microscopy . Other examples are presented in order to highlight the advantages of such a technique applied to small inclusions in thin surface layers.