Nano-Science Activity at Atomic-scale Surface Science Research - - PDF document

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Nano-Science Activity at Atomic-scale Surface Science Research Center (ASSRC) in Yonsei University

Presented by H. W. Yeom

• 2003. 10. 14

Overview of ASSRC

• Director : Prof. C. N. Whang
• Established in 1995
• Funding - Korean Science and Engineering Foundation

(through SRC program) and Yonsei University

• Annul budget - 12 billion won
• Research groups - 15 groups from 8 institutes
• In-house man power - 5 professors, 4 Research professors,

8 Post docs

ASSRC & I PAP, Y on se i U n iv.

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• Atomic structures of atomic

(nano) -scale structures on surfaces

• Electronic structures of atomic

(nano) -scale structures on surfaces

• Fabrication and manipulation of

nanoscale structures on surfaces

• Fabrication of nanodevices and

transport properties

Nano-lettering by scanning tunneling probe on SiO2 thin film

Major Research Areas

ASSRC & I PAP, Y on se i U n iv.

• Synchrotron-radiation photoelectron spectroscopy beam line
• Scanning Tunnelling Microscope
• Atomic Force Microscope
• Scanning Electron Microscope
• Ion-Scattering Spectrometer
• Photoemission Electron Microscope

4 K Scanning Tunneling Microscope Synchrotron-radiation photoelectron spectroscopy system

Major Instruments

ASSRC & I PAP, Y on se i U n iv.

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5 1 1 5 2 2 5 3 P R L A P L P R B J A P O t h e r s 2 1 2 2 2 3

Recent Publications (2001~2003)

28 57 40 Number of papers 2003 (1/2) 2002 2001

ASSRC & I PAP, Y on se i U n iv.

L = # of BP Units × 4a 0

x

z Si atomic chain on Si(111)5X2-Au : Shottkey barrier effect

ASSRC & I PAP, Y on se i U n iv.

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S T M i m a g e s

• f

A u n a n

• l

i n e s

M e t a l

• i

n s u l a t

• r

t r a n s i t i

• n
• f

n a n

• l

i n e s Himpsel’s group, PRL (2002) Yeom’s group, PRL (2003)

Metallic nanowires on Si

ASSRC & I PAP, Y on se i U n iv.

γ-Al2O3 (111) Si (111) 2nm

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[ 1 1 2 ] [ 1 1 ]

[ 1 1 1 ]

Al2O3 /oxidized-Si(111) Al2O3 /clean-Si(111) Ts=750°C Ts=830°C Ts=830°C Ts=750°C

Better crystallinity to grow on the oxidized Si(111).

Growth of epitaxial Al2O3 on oxidized or clean Si(111)

ASSRC & I PAP, Y on se i U n iv.

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Before trapping After trapping Electric transport through DNA - SEM image of trapped DNA

ASSRC & I PAP, Y on se i U n iv.