A Two-Dimensional Bloch-Wave Method for Dynamical RHEED Calculations

Abstract

A new two-dimensional Bloch-wave method is developed for dynamical reflection high-energy electron diffraction (RHEED) calculations. In this two-dimensional Bloch-wave analysis, the traverse energy and the wave field for each Bloch wave are calculated by a stepby-step R-matrix method. The accuracy of the method is critically examined in comparison with Ichimiya's method on the experimental rocking curve of an Si(001)-2 x 1 surface. It is demonstrated that twodimensional Bloch-wave analysis can be used to elucidate the mechanism causing the peaks in rocking curves.

Theoretical analysis of reflection high-energy electron diffraction (RHEED) and reflection high-energy positron diffraction (RHEPD) intensity oscillations expected for the perfect layer-by-layer growth

“…In this context we can say that our approach is similar to the method suggested in Ichimiya (1983). In fact the proposals of Ichimiya (1983) and Zhao et al (1988) are different; however, it was discussed in the literature (Watanabe et al, 1998) that the application of the concepts of Ichimiya (1983) gives nearly the same results as the applica-tion of concepts of Light & Walker (1976) which were employed by Zhao et al (1988). Coming back to the algorithm defined by equation (1), it should be said that there are also some disadvantages in its use.…”

Effect of Surface Plasmons on Energy Filtered RHEED Rocking Curves from a Si(111)-7×7 Surface

“…In branch 8, the backward wave is localized between AL and SL1 and between SL3 and SL4 at the fourth peak. Although the 2D Bloch wave related to the integer rod of the unreconstructed Si(001) surface is localized in the transition region below the integer sidebeam threshold condition [23], the wave related to the integer rod (1,1) of the Si(111) surface (branch 8) is sharply localized between SL4 and BL1 below the fifth peak of the Si(111)-7Â7 surface. This is due to the fact that the transition region exists in the bulk region in the case of the unreconstructed Si(001) surface, but in the surface re- gion in the case of Si(111)-7Â7 surface.…”

“…The method is further discussed in detail by Watanabe et al [23], and briefly outlined below. To obtain 2D Bloch waves, a slab infinite in the x and y directions and finite in the z direction is divided into slices parallel to the surface.…”

“…They do not, however, make explicit use of the site information contained in the 2D Bloch waves used in the calculations of reflection intensities [21,22]. In our previous work [23], an alternative approach to the RHEED theory is explored, which especially treats the forward and backward 2D Bloch waves and easily handles evanescent waves. It is found that the peaks can be classified depending on the type of 2D Bloch waves associated with their formation.…”