Crystalline Perfection of Semiconductor Surfaces by X-Ray Multiple Diffraction

Abstract

In this study, a method is proposed for evaluating the crystalline perfection of semiconductor surfaces. This method takes advantage of the three-dimensional nature of the X-ray multiple diffraction (MD) phenomenon. The effects that crystalline imperfections have on the MD Bragg condition are theoretically investigated. This theory provides information regarding the dynamical (primary extinction) or the kinematical (secondary extinction) regime in which the energy transfer among the MD beams occurs. In dynamical regime when the surface consists of large perfect-crystal regions (low surface-defect density), the method permits analysis of misorientation of these regions in directions parallel and perpendicular to the crystal surface. The perfection of GaAs and Ge (001) surfaces has been investigated using this method after mechanical and/or chemical polishing.