Three-Dimensional Reciprocal-Lattice Analysis Using Azimuth-Scan Reflection High-Energy Electron Diffraction: Determination of Complex Crystal Orientations of Al Grains on Si(111) Surface

摘要

We have applied a three-dimensional (3D) reciprocal-lattice analysis method using a typical reflection high-energy electron diffraction (RHEED) system-all RHEED patterns in scanning sample-surface azimuth are converted into 3D reciprocal-lattice space. This analysis method can determine complex crystal orientations of nanoclusters, islands, and grains with multiple domains, which are difficult to obtain from a small number of non-converted two-dimensional RHEED patterns. For an Al-deposited Si(Ⅲ) surface followed by annealing, we successfully determined new crystal orientations of Al grains: AI(001), AI(012) and AI(011) || Si(Ⅲ) with AI[100] || Si(011). The typical acquisition time of 3D RHEED patterns is 10-20 min, which is shorter than that by a standard X-ray diffraction system with φ and ω scans for 3D reciprocal-lattice mapping. This is one of the advantages of this analysis method, in addition to the convenient observation of in situ vacuum-fabricated nanocrystals on substrate surfaces with high sensitivity.