Electronic properties of atomically abrupt tunnel junctions in silicon

Electronic structure models of phosphorusδ-doped silicon

“…3,4 Phosphorus ␦-doped silicon is particularly interesting for its relevance to nanoelectronic device fabrication including the possibility of quantum computers. 5-7 Various prototype Si:P devices are currently being developed 5,[8][9][10][11][12][13][14][15] in which patterned ␦-doped layers form conducting leads and gate electrodes. These developments warrant and motivate detailed theoretical studies into the baseline electronic properties of phosphorus ␦-doped silicon.…”

Surface gate and contact alignment for buried, atomically precise scanning tunneling microscopy–patterned devices

“…The active region of our devices such as nanowires, 6 dot arrays, 7 tunneling gaps, 8 and nanodots 4 can usually be patterned within a 400ϫ 400 nm 2 STM scan frame and, thus, fits on the central step-free terrace. 1͑h͔͒.…”

“…[2][3][4] Electrical characterization of these atomic-scale devices patterned in ultrahigh vacuum ͑UHV͒ requires alignment of ex situ macroscopic contacts to the buried scanning tunneling microscopy ͑STM͒-patterned device layers once the samples are removed from the UHV environment. 5 Using such marker designs, we have been able to make four-terminal measurements of buried, STM-patterned nanowires, 6 arrays, 7 tunnel junctions, 8 and nanodots. While this problem can be overcome by prepatterning the initial Si substrate with some form of marker structure that can be used to align ex situ contacts, the high temperature anneal ͑Ͼ1100°C͒ required to prepare atomically flat Si surfaces in UHV for STM imaging places severe constraints on the potential types of markers used.…”

Room temperature molecular resolution nanopatterning of cyclopentene monolayers on Si(100) via feedback controlled lithography

“…[12][13][14] Beyond these fundamental studies, recent work has also begun to explore the UHV STM as a nanomanufacturing tool. 15 Progress towards this objective has resulted in an array of sophisticated STM-fabricated device structures including atomically abrupt tunnel junctions, 16 atomic-scale interconnects, 17 single atom transistors, 18 and the controlled growth of three-dimensional nanostructures. 19,20 One important example of a UHV STM-based surface modification technique that has advanced room temperature nanopatterning to the single atom limit is feedback controlled lithography (FCL).…”