Nano electro mechanical systems (nems)

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NANO ELECTRO MECHANICAL
SYSTEMS (NEMS)
What is NEMS?
 The term Nanoelectromechanical systems
or NEMS is used to describe devices
integrating electrical and mechanical
functionality on the nanoscale.
 NEMS form the logical next miniaturization
step from so-called microelectromechanical
systems, or MEMS devices.
NEMS - Definition
 NEMS is the integration of sensors, actuators,
electronics, photonics, energy, fluidics,
chemistry, and biology into a meaningful
system enabled by sub micrometer science
and engineering precision.
Nanowires
 Nanowires such as nanoLED arrays might enable a
new class of nanodisplays.
 But consider fabricating nanowires out of dissimilar
materials such as gallium arsenic on silicon.
 The ability to realize vertical nanowires composed of
metals, semiconductors, and insulators on silicon
and other substrates will enable new types of high
performance, heterogeneous micro- and
nanosystems.
 And they can be formed without the usual
considerations of lattice strain matching that occurs
in microscale dimensions.
Nanowires
NEMS in Nano Biotechnology
 NEMS will also enable other important new
opportunities in the emerging field of
nanobiotechnology.
 The ultrasensitive detection method could replace
complicated optical fluorophore tags and optical
readout methods routinely used by molecular
biologists with a simple electrically measured
parameter—frequency.
 A biocantilever diving board fabricated by Professor
Michael Roukes at CalTech has shown the ability to
detect small mass changes as low as 7 zeptograms,
which is roughly the mass of a single protein
molecule!
Nanoassembly
 The most important area of NEMS opportunity
arises— programmable self-assembly for
heterogeneous nanointegration.
 It is simply called as nanoassembly––a new
manufacturing paradigm that allows for the
directed self-assembly of components into
precise locations on a substrate.
 Nanoassembly might also be used to build
systems on non-planar or 3D surfaces where
traditional monolithic integration has failed.
Approaches to miniaturization
 Two complementary approaches to
fabrication of NEMS systems can be found.
 The top-down approach
 The bottom-up approach
Top-down approach
 The top-down approach uses the traditional
microfabrication methods, i.e. optical and
electron beam lithography, to manufacture
devices.
 Typically, devices are fabricated from metallic
thin films or etched semiconductor layers.
Bottom-up approach
 Bottom-up approaches, in contrast, use the
chemical properties of single molecules to
cause single-molecule components to
 (a) self-organize or self-assemble into some useful
conformation, or
 (b) rely on positional assembly
 This allows fabrication of much smaller
structures, albeit often at the cost of limited
control of the fabrication process.
Future of NEMS
 NEMS devices, if implemented into everyday
technologies, could further reduce the size of
modern devices and allow for better
performing sensors.
 Carbon based materials have served as prime
materials for NEMS use, because of their
highlighted mechanical and electrical
properties.
Conclusion
 In summary, the MEMS revolution that began
at DARPA in the early 1990s will continue to
bring new and more powerful microsystems
to the commercial world and defense
community.
 Therefore, there is no doubt that the Age of
NEMS will produce exciting new capabilities
we are only now beginning to imagine.
Thank You!!!
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