Accessibility of ARPES for Three-dimensionally Architected Si{111}7×7 Facet Surfaces on Micro-patterned Si(110)

Abstract

The creation of three-dimensional (3D) geometrical shapes with atomically ordered surfaces and the investigation of their physical properties are major steps contributing to the development of a new paradigm in surface science. We produced a 3Dpatterned Si sample with atomically flat and reconstructed {111} facet surfaces, and investigated its structural and physical properties. To apply the conventional techniques in surface science to 3D samples with various oriented surfaces, instead of two-dimensional planar samples, an appropriate relationship between the crystallographic surface ordering on the 3D-architected surfaces and the angle-resolved photoelectron spectroscopy (ARPES) setup considering the configuration in 3D space is indispensable. The distinctive and complex low-energy electron diffraction (LEED) patterns reflecting the 3D-arranged facet surfaces showed the realization of atomically reconstructed facet surfaces on 3D-patterned Si. Surface states of the 3D-patterned Si{111} surfaces are mapped by ARPES by considering the 3D geometrical relationship. The selection of the appropriate alignment of the incident electron beam (light) for the target surfaces allows the clear observation of the band dispersion from the produced {111}7×7 facet surfaces in 3D space. Our demonstration of accessibility of ARPES technique could provide useful guidelines for new methodologies, giving a fundamental understanding of 3D-shape-induced novel functionalities.