Monolayer resolution by means of x-ray interference in semiconductor heterostructures

Abstract

We show that the interference of x-ray wave fields in semiconductor heterostructures can be used to detect ultrathin layers having 1 monolayer thickness. A detailed theoretical and experimental investigation on Si/Six Ge1−x heterostructures is presented. The interference effect is studied experimentally by using a high-resolution double-crystal x-ray diffractometer. The diffraction patterns are recorded in symmetrical as well as asymmetrical Bragg geometries and are analyzed by using the dynamical x-ray diffraction theory for distorted crystals.