Atom devices based on single dopants in silicon nanostructures

Research Institute of Electronics, Shizuoka University, 3-5-1 Johoku, Nakaku, Hamamatsu, 432-8011, Japan. .
Nanoscale Research Letters (Impact Factor: 2.78). 07/2011; 6(1):479. DOI: 10.1186/1556-276X-6-479
Source: PubMed

ABSTRACT ABSTRACT: Silicon field-effect transistors have now reached gate lengths of only a few tens of nanometers, containing a countable number of dopants in the channel. Such technological trend brought us to a research stage on devices working with one or a few dopant atoms. In this work, we review our most recent studies on key atom devices with fundamental structures of silicon-on-insulator MOSFETs, such as single-dopant transistors, preliminary memory devices, single-electron turnstile devices and photonic devices, in which electron tunneling mediated by single dopant atoms is the essential transport mechanism. Furthermore, observation of individual dopant potential in the channel by Kelvin probe force microscopy is also presented. These results may pave the way for the development of a new device technology, i.e., single-dopant atom electronics.

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Available from: Daniel Moraru, Sep 27, 2015
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    • "Such a complex transport may also lead to some fine structures within each current peak envelope2526. Further experiments may provide more insights and, based on the present study, open new possibilities for designing dopant-based functionalities272829. "
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    Scientific Reports 08/2014; 4:6219. DOI:10.1038/srep06219 · 5.58 Impact Factor
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    • "Through this vertical manipulation, a single Si atom can be precisely positioned into or extracted from the Sn layer. As the size of devices shrinks to nanoscale or even to atomic scale, besides configuration of nanostructure, the number of isolated atoms of certain species and their location could modify their functionality and performance [12,13]. Therefore, it is sometimes demanded to position dopants at certain sites precisely. "
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    • "Semiconductor nanowires exhibit a variety of unique material properties, including mechanical flexibility, size-dependent optical and electronic properties, and solution processability. In particular, silicon nanowires (SiNWs) have been explored and studied both theoretically [1] and experimentally [2] for a long time, and they have attracted much attention for many applications, such as bipolar and field-effect transistors [3-5], nanosensors [3,6], solar cells [7,8], and energy conversion devices [9,10], but controlled doping with electronic and magnetic impurities remains an important challenge [11-14]. While developing these applications, it is important to control the electrical and optical properties of nanowires (NWs), which strongly depend on the diameter as well as the crystallographic orientation [15] and defect structure of the NWs [16]. "
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