Adaptation of an X-Ray Diffractometer for Thin Film Studies by Total Reflection of X Rays

In studying solid surfaces by the total reflection of x rays it is important to use monochromatic radiation with a narrow angular divergence and to employ a mechanism for precisely aligning the surface of the sample relative to the incident beam. An x-ray monochromator, based on the phenomenon of anomalous transmission in nearly perfect germanium crystals, and a sample holder are described which convert a conventional x-ray diffractometer to an x-ray reflectometer without altering its basic design. Procedures for alignment and operation of the reflectometer and a sample measurement of the thickness and density of a thin titanium film are presented.