SpaceFAB for Ultra-Fine Positioning of the Sample
The Beamline 6.1.2 (XM-1) at Advanced Light Source (ALS), Berkeley, is dedicated to X-ray microscopy and research on nanoscale magnetism. The Center for X-Ray Optics in Berkeley is a multi-disciplined research group within Lawrence Berkeley National Laboratory‘s (LBNL) Materials Sciences Division (MSD).
In the X-Ray transmission microscopy, the sample has to be positioned outside the vacuum, but very close to the beam exit window to avoid absorption in air; "close" being on a scale of some hundreds of micrometers. The spatial resolution of the X-ray beam is 10 nm, so position resolution was requested in the same range.
The solution was a customized 6-degrees-of-freedom SpaceFAB design using stepper motors for excellent position control, plus an elevation stage with down to 50 nm resolution to position the sample in the direction of the beam.
