The local density of states (LDOS) at the epitaxially grown InAs surface on a GaAs(111) A substrate were characterized using low-temperature scanning tunneling microscopy. Using dI/dV signal mapping, LDOS standing waves were clearly imaged at point defects and within nanostructures. Measurement of the wavelength as a function of bias voltage showed a nonparabolic dispersion relation for the conduction band. The observed wave features originate from the Friedel oscillations of the two-dimensional electron gas in the semiconductor surface accumulation layer.

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Molecular beam epitaxy and scanning tunneling microscopy (STM) patterning are combined to form highly doped, planar devices in silicon at the atomic level. The absolute device location is registered to microscopic markers (see image; scale bar: 50 μm) for the alignment of surface contacts, enabling the correlation of the electrical properties of atomically controlled devices such as nanowires, tunnel junctions, and nanodots to the dopant location, monitored using high‐resolution STM techniques.

The local density of states (LDOS) within tetrahedral InAs structures, formed at the surface of InAs/GaAs(111)A, has been characterized using low-temperature scanning tunneling microscopy. The LDOS of the lowest four zero-dimensional (0D) discrete levels have been imaged in structures with a comparable size to the electron wavelength. The LDOS inside the structures is observed to be higher than that of the surrounding area at intervals of the level separation. This feature indicates the singularity of the LDOS close to the 0D resonant levels.