X-Ray Topography of the Subsurface Crystal Layers in the Skew Asymmetric Reflection Geometry

Abstract

The technique of X ray topography with the asymmetric reflection geometry of X-ray diffraction presented in this paper as useful tool for structural characterization of materials, particularly, epitaxial thin films and semiconductor multi-layered crystal systems used for the optoelectronic devices. New possibilities of this technique for a layer-by-layer visualization of structural changes in the subsurface crystal layers are demonstrated for semiconductors after various types of surface treatment, such as chemical etching, laser irradiation and ion implantation.

Методы Рентгеновской Дифракционной Топографии (О Б З О Р)

“…Тогда, во-первых, расширение волнового фронта дифрагированной волны по сравнению с фронтом падающей волны позволяет получать топограммы от тонких приповерхностных слоев монокристалла сравнительно большой площади. Во-вторых, согласно формуле (3), уменьшение угла скольжения приводит к уменьшению глубины проникновения РЛ в приповерхностные слои кристалла [48,49].…”

X-ray topography of subsurface crystal layers

“…It is also highly efficient to use asymmetric reflections followed by rotation of the sample around the diffraction vector (Grigoriev et al, 2016). But no less effective is the diffraction scheme for which the angle between the reflecting plane and the crystal surface is slightly larger than the value of the Bragg angle (Fodchuk & Kshevetsky, 1992;Fodchuk et al, 1995aFodchuk et al, , 2009Swiatek & Fodchuk, 2016):…”

“…1 and 2). In previous work (Swiatek & Fodchuk, 2016) it has been noted that this technique of topography opens up new possibilities for layer-by-layer visualization of structural changes in the near-surface layers of a crystal and can also be used in a double-crystal arrangement for determining the strain values in near-surface layers (Fodchuk & Kshevetsky, 1992;Fodchuk et al, 1995b).…”

“…(a) An increase of the extent of the wavefront for the diffracted beam in comparison with the incident beam (b ¼ j h j= 0 ) gives the possibility to obtain topograms from thin near-surface layers of comparatively large area in a single crystal (Swiatek & Fodchuk, 2016). It is important that the angle of diffraction ( h ) is rather wide ( h !…”

“…The use of the rocking curve method is also valid to study rotational and dilatation components of the lattice strain in silicon crystals by analyzing the dependences of the integrated intensity distribution, the half-width of the reflection curve and the peak intensity on the angular deviation from the Bragg angle (Tsoutsouva et al, 2015). In addition, various modifications of the topographic Berg-Barrett method are still quite effectively used today to estimate the quality of the structure of semiconductor materials (Black & Long, 2004;Lü bbert et al, 2000;Lü bbert & Baumbach, 2007;Swiatek & Fodchuk, 2016).…”