Jpn. J. Appl. Phys. 40 (2001) pp. L29-L32 |Next Article| |Table of Contents|
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Letter
Mechanism of Potential Profile Formation in Silicon Single-Electron Transistors Fabricated Using Pattern-Dependent Oxidation
Seiji Horiguchi,
Masao Nagase,
Kenji Shiraishi,
Hiroyuki Kageshima,
Yasuo Takahashi and
Katsumi Murase
NTT Basic Research Laboratories, 3-1 Morinosato Wakamiya, Atsugi, Kanagawa 243-0198, Japan
(Received June 1, 2000; revised manuscript revised October 3, 2000; accepted for publication November 27, 2000)
The origin of the potential profile in silicon single-electron transistors (SETs) fabricated using pattern-dependent oxidation (PADOX) is investigated by making use of the geometric structure measured by atomic force microscope (AFM), the bandgap reduction due to compressive stress generated during PADOX obtained using the first-principles calculation, and the effective potential method. A probable mechanism for the formation of the potential profile responsible for SET operation is proposed. The width reduction in the silicon wire region in the SET produces a tunnel barrier, while the compressive stress lowers the bottom of the conduction band through the bandgap reduction and forms a potential well corresponding to an island in the tunnel barrier.
KEYWORDS:
silicon single-electron transistor, pattern-dependent oxidation, stress effect, strain effect, first-principles calculation, atomic force microscope, effective potential
URL:
http://jjap.ipap.jp/link?JJAP/40/L29/
DOI: 10.1143/JJAP.40.L29
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