Improved Techniques of Lattice Parameter Measurements Using two X-Ray Beams

Abstract

AbstractTwo kinds of improved techniques are described for precise measurement of lattice parameters with an accuracy of 1 ∼7x10-5, in both of which a differenoe of Bragg angles between two X-ray beams such as K α1 and K β1 is measured.In the first technique, which was applied to relatively imperfect crystals such as gallium arsenide, gallium arsenide phosphide, and gallium phosphide, two different diffraction planes were utilized for two radiations such as CuK α1 and CuK β1 in order to reduce the difference of the Bragg angles to the order of several minutes of arc.In the second technique, which was applied to a nearly perfect crystal such as silicon, a double crystal arrangement of parallel setting was used, where lattice parameter of the specimen was relatively measured in comparison with the one of the first crystal which was known beforehand.