• MEMS is a technology of very small devices. It is a combination of
mechanical functions and electrical functions on the same chip
using micro fabrication technology.
• MEMS are made up of components between 1 to 100 micrometers
• MEMS devices generally range in size from 20 micrometers to a
Fabrication of MEMS
Electron beam lithography
Ion beam lithography
Ion track technology
Physical deposition :
Physical deposition consists of a process in which a material is removed from a
target, and deposited on a surface
Chemical deposition :
Chemical deposition techniques include chemical vapor deposition, in which a
stream of source gas reacts on the substrate to grow the material desired.
Patterning of MEMS is the transfer of a pattern into a material.
Lithography is a widely used process in patterning of mems .
Examples of lithography are– Photolithography, Electron beam lithography, Ion
beam lithography, Ion track technology, X-ray lithography.
Wet Etching :
• Wet chemical etching
consists in selective removal
of material by dipping a
substrate into a solution
that dissolves it.
• The chemical nature of this
etching process provides a
Dry Etching :
• Dry etching can be done in
three ways and they are –
a) Reactive ion etching (RIE)
b) Sputter etching
c) Vapor phase etching.
Designing an MST/MEMS device is basically an iterative process; the
design is put into a simulation loop, improved and resubmitted for
simulation until the design fits the demands.
It is seldom possible to use design methodologies and tools from
traditional industries working with larger dimensions due to the
fundamental differences related to the order of magnitude of the typical
Metal can package
• In medicine
A MEMS is a device that can be
implanted in the human body.
• MEMS surgical tools provide the
flexibility and accuracy to perform
• BIO MEMS
Bio-mems are used to refer to the
science and technology of operating at
the micro scale for biological and
• In automotives :
Heavy use of mems is found in air
bag systems, vehicle security
system, inertial brake lights, rollover
detection, automatic door locks etc.
• As gyroscope:
Inexpensive vibrating structure
gyroscopes manufactured with
MEMS technology have become
widely available. These are
packaged similarly to other integrated
circuits and may provide either
analog or digital outputs.
• In microphones:
The mems microphone also called
as microphone Chip is widely used
in the present day communication
• In military :
Micro-electro mechanical system (MEMS)
technology help projectiles to reach their
• In accelerometers:
• MEMS accelerometers are widely used in cars
for airbag deployment and in consumer
electronics applications such as smart
phones, gaming devices for sensing motion
• In sensors:
A sensor is a device which receives and
responds to a signal when touched. A
micro sensor reaches a significantly higher
speed and sensitivity compared with
• Apart from these applications mems are also used in many fields in
the present world
• They are used to detect earth quakes, in gas shut off, in shock and
• Inkjet printers and micro scanners also involve the use of mems.
• Mems is used in Optical switching technology in which, switching
technology and alignment for data communications is done.
Advantages and disadvantages
Minimize energy and
Improved accuracy and
costly compared to
Design includes very
• This enabling technology
promises to create entirely
new categories of
• MEMS will be the
indispensible factor in
• As with all emerging
technologies had been
predicted to revolutionize
technology and our lives
The future of MEMS is integrally linked to market trends in general and
driven by the increasing demand to monitor and control our
environment and the equipment and instruments we use in our daily
In order to avoid the need for a multitude of wires, such sensors must
be self sustaining and able to communicate wirelessly.
As a result, not only more sensors are needed, but also small energy
generating modules and wireless transmission components. Clearly, the
increased numbers of devices will drive size reduction which in turn will
enable higher levels of integration.