Kikuchi Lines from Etched Copper Crystal

Abstract

IT is well known that a cross-grating pattern of spots is produced when a fast electron beam is incident, at a small angle, on the etched surface of a single crystal. Two explanations have been given of this phenomenon. Thomson¹ showed that the effect would arise if the electrons passed through small projections on the surface, while Germer² attributed it to distortion of the crystal lattice. When etched single crystals of zincblende and galena were studied by Tillman³, he found Kikuchi lines to be present in addition to the cross-grating and, as has been pointed out previously⁴, the presence and sharpness of Kikuchi lines may be taken as a criterion of the degree of perfection of the crystal lattice.