<html>
Pozdravljeni,<br>
ker je bil vmes vikend in je mogoce kdo spregledal obvestilo o
predavanju, vas se enkrat vljudno obvescam, da je danes:<br><br>
<b>PREDAVANJE IJS<br><br>
<font size=4 color="#FF0000">ponedeljek, 21. avgusta 2006, ob 13.
uri<br><br>
Kolarjeva predavalnica (K7),<br>
Institut Jozef Stefan, Jamova 39, Ljubljana<br><br>
</font><font size=4 color="#0000FF">prof. dr. Lian-Mao Peng<br>
</b></font><font color="#0000FF">Key Laboratory for the Physics and
Chemistry of Nanodevices and Department of Electronics, Peking
University, Beijing, China<br><br>
</font><font size=4 color="#0000FF"><b>"In-situ Fabrication,
Manipulation and Property Measurements of Single Nanotubes and Nanowires
with Near Atomic Resolution"</b></font> <br><br>
<font color="#0000FF">Carbon nanotube (CNT) and nanowire materials are
important building materials for nanotechnology. These materials may be
synthesized via a range of physical and chemical methods, and new
nanotube and nanowire materials are produced every day. Measurements on
individual nanostructures remain, however, difficult and it is even more
challenging to control the property of these nanomaterials via structure
modification at near atomic resolution. A very promising and perhaps the
best method to tackle this problem is to combine the scanning tunnelling
microscope (STM) with electron microscope (EM) so that manipulation and
structure modification may be made via a highly controllable fashion on
individual nanostructure [1-3]. <br><br>
CNT can be cut, manipulated and used to form complicated patterns. This
operation requires a correlated manipulation of the CNT by two
independent nanomanipulators [1], and in principle complicated CNT
circuit may be constructed this way and its electric characteristics may
be measured at each step of the pattern construction. While it is very
convenient to carry out manipulation and measurement on nanostructure in
a scanning electron microscope (SEM) either on or above a substrate, the
resolution of the SEM is limited and the vacuum level is typically not as
good as in a transmission electron microscope (TEM). The higher
resolution and vacuum level in a TEM has been utilized for revealing the
importance of the CNT tip structure on its electron field emission
characteristics [4] and effects of deformation on the conductance of the
CNT [5]. In particular experiments of this type show clearly that the
conductance of the large diameter multi-walled CNT is not easily affected
by deformation etc. and these CNTs may in principle be used in the
fabrication of novel nanoelectronic circuit as interconnects [5].
<br><br>
A quantitative analysis of the electric transport property of the
semiconducting nanowire also requires the detailed structure of the
contact and nanowire. Two terminal I-V characteritics may be measured
inside TEM as shown in Fig. 3, and the diameter, length etc. of the
nanowire may readily be obtained from TEM imaging and varied during
experiments providing valuable input for the quantitative analysis of the
transport property of the nanowires[6].<br><br>
References<br>
[1] L.-M. Peng et al., MICRON 35 (2004) 495<br>
[2] Q. Chen and L.-M. Peng, Appl. Phys. Lett. 84(24) (2004) 4920<br>
[3] Q. Chen, S. Wang and L.-M. Peng, Nanotechnology 17 (2006) 1097<br>
[4] M.S. Wang et al, J. Phys. Chem. B109(1) (2005) 110; B110 (2006) 5423,
9397<br>
[5] M.S. Wang et al., Adv. Funct. Mater. 15, (2005) 1825; 16 (2006)
1462<br>
[6] Z.Y. Zhang et al., Appl. Phys. Lett. 88 (2006) 073102<br><br>
</font><font size=4 color="#800000"><b>Predavanje bo v
anglescini.<br><br>
<br>
</b></font><x-sigsep><p></x-sigsep>
Tamara Matevc<br>
tajnica Odseka za kompleksne snovi<br>
Institut Jozef Stefan<br>
Jamova 39<br>
SI - 1000 Ljubljana<br>
tel.: +386 1 477 3220<br>
fax: +386 1 477 3998<br>
e-mail: tamara.matevc@ijs.si</html>