The Principle of Dislocation Analysis by Coherent Optical Scattering from a Defect‐Etched Surface

Abstract

This paper describes a new technique for rapid analysis of dislocations in solids. The technique consists of shining a HeNe laser beam (λ = 6328Å) on a defect-etched surface and analyzing the characteristics of the light scattered by the sample to determine the type and the density of dislocations. It is shown that: (i) the shape of the far-field pattern determines the propagation direction of dislocations near the surface; and (ii) the total integrated light flux scattered by the illuminated surface (normalized by the incident flux) is related to the dislocation density by a simple linear relation. Requirements of a defect etch suitable for this technique are described. An experimental setup for high-speed, high-resolution mapping of dislocation density is given. Application of this technique for mapping dislocation density (nd) in polycrystalline substrates is also discussed. © 1988, The Electrochemical Society, Inc. All rights reserved.