Research, the technology leader in scanning probe and atomic force microscopy,
and Oak Ridge National Laboratory (ORNL) have just received the prestigious
Microscopy Today Innovation Award for the development of Band Excitation (BE),
a new breakthrough scanning probe microscopy (SPM) technology.
Band excitation allows more rapid probing of energy dissipation at the nanoscale
than previously possible, enabling scientists to characterize a sample’s
electrical, magnetic, and mechanical energy conversion and dissipation properties
at standard imaging rates.
Band Excitation captures the full tip dynamics during a scan, and therefore let’s you see the transfer function or ‘cantilever tune’ everywhere. From this information one can see maps of dissipation and non-linearities directly. Shown is a 15X15 micron BE acoustic force microscopy scan of a polymer blend from which the Q-factor has been extracted. A clear contrast can be seen between the different constituent materials. Also shown are the average transfer functions over the regions indicated by blue and red dots on the map. The ability to capture tip motion in greater detail makes nanoscale measurements of material properties possible.
The applicability of SPM for mapping energy transformations and dissipation
has previously been limited by the fundamental operation mechanism employed
in nearly all conventional SPMs – that is, they operate at only one frequency
at a time. However, in order to fully capture the dynamic interactions of the
SPM tip and the surface – of which dissipation is a critical component
– one must know how this interaction varies at many frequencies. BE achieves
this breakthrough in information gathering by exciting and detecting the tip
dynamics at many frequencies simultaneously – like seeing in color as
opposed to black and white, or listening to a chorus of singers instead of a
single note. In BE, the conventional sine wave is substituted by a synthesized
digital signal that spans a continuous band of frequencies and monitors the
response within the same frequency band. This allows ~100x improvement in data
acquisition speed compared to currently available commercial technologies without
decreasing the signal to noise ratio. A full response spectrum can then be collected
in the amount of time required for obtaining a single pixel in standard SPM.
BE will be an important technology in understanding energy dissipation in a
diverse range of technologies, including electronics, information technology,
energy storage and transport, and more.
“We’re extremely excited to have won this prestigious award,”
said Roger Proksch, President of Asylum Research. “Our collaboration with
the Oak Ridge National Laboratory has put forth many new cutting-edge developments
in the field of SPM, including the Piezo Force Module and Switching Spectroscopy
PFM. The Band Excitation method presents a fundamentally new method for data
acquisition and processing in SPM. Asylum Research and our collaborators continue
to lead the industry with technical innovation as confirmed by this award.”
“We believe Band Excitation will be the harbinger of a new family of
SPMs,” said Dr. Sergei Kalinin, co-inventor and researcher at the Center
for Nanophase Materials Sciences (CNMS) at ORNL. “This method provides
an alternative to well-known lock-in-based detection methods, and can revolutionize
this field by providing the potential for quantitative and artifact-free dissipation
imaging. We are looking forward to developing new applications for BE through
our partnership with Asylum Research.”
"This award acknowledges the important step forward that this technique
represents and signals where the field of microscopy can and will go in the
future," noted Dr. Stephen Jesse, another co-inventor from the CNMS. "The
speed and flexibility of the latest generation of Asylum SPM controllers permit
the fine tuning and fast acquisition of data streams needed to take us from
mere imaging to an arena of information-rich insight into cantilever-surface
interactions and material functionality."