2. INTRODUCTION
Nano-Electro-Mechanical systems (NEMS)
integrate electrical and mechanical functionality
on the nanoscale.
The Nano mechanical components are fabricated
using compatible “micromachining” process.
3. Nano electro mechanical devices promise to
revolutionize measurements of extremely small
displacement and extremely weak forces,
particularly at the molecular level.
NEMS devices can be so small that hundreds of
them can be fit in the same space as one single
micro device that performs same function.
4. Nano-electronic integrated circuits allow nano systems to
sense and control the environment.
In Nems devices the sensors gather the information from
surrounding environment through measuring
mechanical, chemical, biological, chemical and optical
phenomenon.
The electronics then process the information derived form
the sensors.
Through some decision making capability direct the
actuators to respond by moving, regulating and filtering.
5. Electro mechanical systems:
The device illustrates the two principal components
common to most electromechanical systems
irrespective of scale:
a mechanical element:includes moveable structures
such as beams,gears.
transducers.:small motors and integrated circuits.
the output of an electromechanical device is the
movement of the mechanical element.
6. BENEFITS OF NANO MACHINES
The small mass and size of Nano machines gives
them a number of unique attributes that offer
immense potential for new applications and
fundamental measurements.
A second important attribute Nano machines is that
they dissipate less energy.
7. Nano machines are extremely small .
Nano machines are ultra low power devices.
Fundamental power scale is defined by the thermal
energy divided by the response time
8. FABRICATION OF NEMS DEVICE
There are three Basic building blocks in NEMS
technology.
Deposition processes.
Lithography.
Etching processes.
9. Deposition Process :
Chemical methods used in NEMS deposition
process.
o Chemical vapour deposition.
o Epitaxy.
12. Lithography :
Lithography in the NEMS context is typically the
transfer of a pattern to a photosensitive material by
selective exposure to a radiation source such as light.
A photosensitive material is a material that
experiences a change in its physical properties when
exposed to a radiation source.
13. Pattern Transfer :
Fig 3: Transfer of a pattern to a photosensitive material
14. Figure 4:a) Pattern definition in positive resist, b) Pattern
definition in negative resist.
15. Alignment :
Inorder to make useful devices the patterns for
different lithography steps that belongs to a single
structure must be aligned to one another.
It is important for each alignment mark on the wafer
to be labeled so it may be identified, and for each
pattern to specify the alignment mark to which it
should be aligned.
16. Exposure :
This parameter is required in order to achive accurate
pattern transfer from the Mask to the photo sensitive
layer.
Different Photo resist exhibit different sensitivity to
different wavelengths
17. Etching :
It is necessary to etch the thin films previously
deposited or the substrate itself.
There are 2 class of etching process.
Wet etching.
Dry etching.
19. APPLICATIONS OF NEMS
Accelerometer :
NEMS accelerometers are quickly replacing
conventional accelerometers for crash air-bag
deployment systems in automobiles.
Figure 6 : Accelerometer(air bags)
20. Nano nozzles:
Another wide deployment of NEMS is their use
as nano nozzles that direct the ink in inkjet
printers.
They are also used to create miniature robots
(nano-robots) as well as nano-tweezers.
NEMS have been rigorously tested in harsh
environments for defense and aerospace where
they are used as navigational gyroscopes.
21. NEMS in Wireless :
A 3G “smart” phone will require the functionality
of as many as five radios – for TDMA, CDMA,
3G, Bluetooth and GSM operation. A huge
increase in component count is required to
accomplish this demand.
22. Thermal actuator :
Thermal actuator is one of the most important NEMS
devices, which is able to deliver a large force with large
displacement.
23. Thermal actuator :
Thermal actuator is one of the most important NEMS
devices, which is able to deliver a large force with large
displacement.
24. DRAWBACKS
NEMS technology is currently used in low- or
medium-volume applications. Some of the obstacles
preventing its wider adoption are:
Limited Options
Packaging
Fabrication Knowledge Required
25. FUTURE OUTLOOK
NEMS offer unprecedented and intriguing
opportunities for sensing and fundamental
measurements.
In the future, complex molecular-scale mechanical
devices will be mass-produced by placing millions of
atoms with exquisite precision or by some form of
controlled self-assembly. This will be true
nanotechnology.
26. The focus on the exploration of NEM-physics and the
development of NEM-devices can be used as extremely
sensitive sensors for force and mass detection down to
the single molecule level, as high-frequency resonators
up to the GHz range
Typically, high-frequency electrical resonators have Q
values less than several hundred.
27. CONCLUSION
Nano-systems have the enabling capability and
potential similar to those of nano-processors .
Since NEMS is a nascent and synergistic
technology, many new applications will emerge,
expanding the markets beyond that which is
currently identified or known.
28. NEMS is forecasted to have growth similar to its
parent IC technology.
For a great many applications, NEMS is sure to be
the technology of the future.
29. REFERENCES
[1] James E.Hughes Jr;Massimiliano Di Ventra;Stephane
Evoy(2004).”Introduction to nanoscale science and
technology”.
[2] Despont
M;Brugger,J;DRECHSLER,U;Durig,U;Haberle,W,Lut
wyche,M;Rothuizen,H;Stutz,R,et al(2000).”VLSI-
NEMS chip for parallel AFM data storage”.
[3] Ke,Changhong;Espinosa,Horacio
D(2005).”Numerical analysis of nanotube_based
Nems devices_part 1”.
[4] “Global Market of NEMS projections”
