X線回折顕微法による結晶完全度の研究(<特集>Growth and Characterization of Silicon Crystals)

抄録

X-ray diffraction topography is one of the powerful non-destructive methods to characterise crystal perfections. The method is complementary to "goniometry" ; for example, the measurement of the rocking curve due to single crystals. The present article is divided into four sections. I. Traverse and Section Topographs II. The Section Topograph of Perfect Crystals III. Comparison between Theory and Experiment IV. Discussion In the first two sections, the experimental and theoretical backgrounds about the observation of Pendellosung fringes are briefly reviewed. Emphasis is put on explaining the wave-optical nature of the fringes. In the last two sections, the work of Wada and Kato (Acta Cryst. A33 (1977) 161) on the intensity distribution of the section topograph is reviewed. The fringe profile could be represented well by the sum of two terms: The dynamical term and the kinematical term. The ratio, however, was very small and an order of 10^<-3> in magnitude, evaluated at the depth zero, in the case of available perfect crystals. The diffraction represented by the kinematical term is infered to be created along the incident beam by slightly distorted lattice. For this reason the magnitude of the kinematical term can be used for a measure to characterise the perfection of very perfect crystals.