Critical aspects of scanning X-ray/optical interferometry

Abstract

We are presently developing and testing an X-ray and optical interferometer capable of millimeter scans. Our goal is to reduce the relative uncertainty in the measurement of the (220) lattice spacing of a silicon crystal to a few parts in 10/sup 9/. In a new series of measurements, the value obtained with our previous experimental set-up is confirmed and the bounds to the measurement uncertainty are investigated.