Soft X-ray optics characterization on SURF II

Abstract

We describe the present capabilities and future plans for soft X-ray optics characterization at the NIST storage ring, SURF II. The existing facility is made up of a monochromator and a reflectometer capable of characterizing the reflectivity of soft X-ray devices, including multilayers, gratings and grazing incidence optics. This system can also be used to characterize the transmission of components such as filters. The present capabilities include a wavelength range from 80 Å to 600 Å. The reflectometer will handle components up to several cm in diameter and its detector can be scanned in two independent angular directions. This allows the mapping of scattered photons from the sample, as well as the measurement of reflectivity as a function of angle and wavelength. Results of measurements on users' samples will be shown.We plan to modernize and expand the capabilities of this facility in the following ways:(1) Construct a new monochromator capable of scanning wavelengths from 30 Å to greater than 600 Å.(2) Construct a new reflectometer with independent, computer-controlled angular and translational motion for the sample and detector. This will permit automated wavelength scans and Θ/2Θ scans at fixed wavelengths, as well as mapping of the sample surface. The reflectometer will have a multidetector capability. It will also allow the measurement of optical constants of thin films.(3) Construct an optical test bench for characterizing the imaging properties of focusing optics.Other considerations for expanded capabilities, depending on the needs of the soft X-ray user community, include:(1) In-situ deposition of thin films with a vacuum transfer capability.(2) Provisions for other types of characterization, such as scanning tunneling microscopy (STM) and interferometric profilometry.