HIGH-RESOLUTION TRIPLE-CRYSTAL X-RAY-DIFFRACTION EXPERIMENTS PERFORMED AT THE AUSTRALIAN NATIONAL BEAMLINE FACILITY ON A SILICON SAMPLE WITH LATERAL PERIODIC SUPERSTRUCTURE

The synchrotron X-ray results reported here are from the first high-re solution triple-crystal diffraction experiments performed at the Austr alian National Beamline Facility (ANBF). At the centre of the ANBF is a multipurpose high-resolution two-axis vacuum X-ray diffractometer. T he Si(111) sample studied has been implanted with B+ ions through a on e-dimensional SiO2 strip pattern with a 5.83 mum period and 4 mum open region, to produce a sample with a periodic superstructure in the lat eral direction. The triple-crystal data were collected in the form of two-dimensional intensity maps in the vicinity of the 111 Bragg peak. Results collected in both air and vacuum are compared, as are results with and without the oxide layer. The data collected in vacuum indicat e that it is possible at the ANBF to measure lattice distortions perpe ndicular to the sample surface with a 50 angstrom depth resolution.