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NT NEWS NT-MDT in the USA
News Letter # 2, December 2014
Follow up on 2014 MRS Fall
Meeting & Exhibition in Boston Traditionally, the MRS Fall meeting is a large
gathering of US and international scientists, and
SPM‐related symposiums always attract their
attention. This year the attendees paid a special
awareness to symposium PP: Advances in Scanning
Probe Microscopy for Multimodal Imaging at the
Nanoscale, co‐sponsored by NT‐MDT. The latest
developments of techniques, which offer an optical
resolution below the diffraction limit as well as
chemical identification, were presented and
discussed at this well attended meeting. We have
also participated in this event by contributing two
talks, and the same topic was a subject of our live
demonstration of Tip Enhanced Raman Scattering
on different samples, which was performed at one
of our two booths. At another booth, NT‐MDT has
introduced a novel Thermal Cabinet for our SPM
microscopes, see the photo above. The attractive
cabinet provides not only microscope isolation from
the acoustic noise and mechanical vibrations, but
also ensures unique temperature stability with
variations less than 0.01 degree. This instrument
environment enables low thermal drift SPM
measurement, which is important for many
applications including but not limited to high‐
resolution imaging in different AFM modes
(amplitude modulation, Hybrid and contact modes).
From the Social Networks Several groups of the professional Internet network
“LinkedIn” are involved in discussions about
different aspects of scanning probe microscopy.
One of the recent topics of “Scanning Probe
Microscopy Society” is the novel approach in
recording and analysis of force curves in Hybrid
mode, which is the non‐resonant oscillatory
technique, introduced a couple of years ago by NT‐
MDT. The related document describing IsoDynamic
Force Microscopy can be found at
https://www.youtube.com/watch?v=_ftYMn‐7te0.
Merry Xmas and Happy 2015!
It contains a short movie presenting the
visualization of elastic depression of poly (dimethyl
siloxane) lamellar structures, which was recorded
simultaneously with the force curves. Actually, the
use of the force curves in AFM modes for the force
control during imaging is also complemented by
their on‐line and off‐line analysis as well as for the
extraction of the local mechanical and electric
properties simultaneously with the surface
profiling. A new Application Note, in which these
questions are considered in details, is in progress.
From the Laboratories Thermoelectric measurements with AFM have been
demonstrated by several research groups, and this
method becomes a valuable addition to the family
of AFM‐based electric modes. The essence of this
method is a precise detection of the voltage
between the Pt‐coated AFM probe and a sample
and its changes at different temperatures. This
phenomenon is broadly used in thermocouples and
described by Seebeck coefficient which depends on
the sample chemical nature. Our attention to the
AFM thermoelectric measurements was inspired by
the collaborative efforts with the group of Prof.
Rachel Segalman (UCSB), whose earlier efforts has
been documented in the paper: P. Reddy et al
Science 315, 1568 (2007). The straight
demonstration of this effect has been achieved in
studies of an incomplete metal alloy of Bi and Sn.
These metals are characterized by substantially
different Seebeck coefficients: Bi – 72V/˚C, Sn – 1.5V/˚C. The image below shows the voltage map,
which was recorded at elevated temperature of
55˚C. The distinctive contrast of different domains
(practically not‐noticeable at room temperature)
allows their assignment to the individual
constituents of this alloy. This is one of the possible
ways of compositional mapping of the
heterogeneous materials. Single‐pass Kelvin Force
Microscopy and quantitative nanomechanical
measurements in the Hybrid mode were already
described in NT‐MDT applications related to the
Bi/Sn alloy. It is worth noting that the AFM‐based
thermoelectric study helped to reveal the local
defects in epitaxial graphene: S. Cho et al. Nature
Materials 12, 913 (2013)
Topography and voltage map of Bi/Sn alloy at 55˚C. Forthcoming NT‐MDT Events: 2015 January 14: Webinar “Characterization of Materials
with a Combined AFM/Raman Microscope” based
on the AFM/Raman data obtained in the combined
Raman microscope DXR of Thermo Fisher Scientific
and AFM unit NTEGRA Spectra from NT‐MDT.
February: NT‐MDT AFM/Raman Workshop at
Carnegie Mellon University (Pittsburgh, PA), which
includes technical presentations and demonstration
sessions on several NT‐MDT microscope.
Cool AFM Images
Topography of polymer “honeycomb” template (left and center) and a hexagonal packing of
polystyrene latex particles (right). Amplitude modulation mode.