This document discusses microsystems and MEMS. It covers micro sensors and actuators, components of microsystems including sensors, actuators and a processing unit. It compares microelectronics and microsystems technology and discusses intelligent microsystems that incorporate signal processing. Examples of successful MEMS devices are provided like micro gears, motors, turbines and switches. The principles of science involved in microsystem design are outlined. Animation demos of various MEMS devices are listed at the end.

1. Department of Instrumentation & Control Engineering, MIT, Manipal
Lecture #03
MEMS & Micro Systems
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2. Department of Instrumentation & Control Engineering, MIT, Manipal
Contents
1. Micro Sensors & Actuators
2. Components of Microsystems
3. Comparison of ME & MST
4. Intelligent Microsystems
5. Further
6. Successful Devices
7. Principle Science
8. Animation Demo
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3. Micro Sensors & Actuators
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The core element in MEMS generally consists of two principal
components: a sensing or actuating element and signal transduction unit.
MEMS as a microsensor:
Micro sensors are built to sense the existence and the intensity of certain
physical, chemical or biological quantities, such as temperature, pressure,
force, sound, light, nuclear radiation, magnetic flux and chemical
compositions.
Common sensors include biosensors, chemical sensors, optical sensors,
thermal and pressure sensors.
S.Meenatchisundaram, Department of Instrumentation & Control Engineering, MIT, Manipal

4. Micro Sensors & Actuators
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MEMS as a microactuators:
The transduction unit converts the input power supply into the form such as
voltage for a transducer, which functions as the actuating element.
There are several ways by which microdevice components can be actuated
such as electrostatic forces.
S.Meenatchisundaram, Department of Instrumentation & Control Engineering, MIT, Manipal

5. A microsystem is an engineering system that contains MEMS components
that are designed to perform specific engineering functions.
Usually a microsystem will be in meso-scale even though the MEMS
components can be produced in microns.
A microsystem includes three major components of micro sensors,
actuators and a processing unit as shown in figure.
Components of Microsystems
5S.Meenatchisundaram, Department of Instrumentation & Control Engineering, MIT, Manipal

6. One popular actuation method involves electrostatic forces generated by
charged parallel conduction plates, or electrodes separated by a dielectric
material such as air.
The arrangement is similar to that of capacitors.
The application of input voltage to the plates (i.e., the electrodes in a
capacitor) can result in electrostatic forces that prompt relative motion of
these plates in normal direction of aligned plates or parallel movement for
misaligned plates.
These motions are set to accomplish the required actions. It is used in many
microactuators such as microgripper.
Components of Microsystems
6S.Meenatchisundaram, Department of Instrumentation & Control Engineering, MIT, Manipal

7. Components of Microsystems
7S.Meenatchisundaram, Department of Instrumentation & Control Engineering, MIT, Manipal

8. Most microsystems are designed and constructed to perform single
functions. Incorporating signal processing and closed loop feedback control
systems in a microsystem makes the integrated system as “intelligent”
systems.
Intelligent Microsystems
8S.Meenatchisundaram, Department of Instrumentation & Control Engineering, MIT, Manipal

9. Intelligent Microsystems
9S.Meenatchisundaram, Department of Instrumentation & Control Engineering, MIT, Manipal

10. S.Meenatchisundaram, Department of Instrumentation & Control Engineering, MIT, Manipal
Microelectronics Micro system Technology
Uses Single Crystal Silicon (SCS)
die, Si compounds.
Uses SCS die and GaAs, quartz,
polymers and metals
Stationary structures May involve moving components
Primary 2D structures
Fewer components in assembly
Complex 3D structures
Many components to be assembled.
Mature IC design methodology
Lack of engineering design
methodology and standards
Manufacturing techniques are
proved and well documented
Distinct Manufacturing techniques
Packaging technology is well
established
Packaging Technology is at the
infant stage.
Comparison of ME & MST
10S.Meenatchisundaram, Department of Instrumentation & Control Engineering, MIT, Manipal

11. Working Principle based on Applications
Materials
Process
Basics of Mechanics
Design of MEMS Devices
Further
11S.Meenatchisundaram, Department of Instrumentation & Control Engineering, MIT, Manipal

12. Micro Gear: A gear made with ceramics, pitch of the gears in the order of
100 microns is shown in figure. Made by a process called LIGA.
Successful Devices
12S.Meenatchisundaram, Department of Instrumentation & Control Engineering, MIT, Manipal

13. Micro Motor: An electrostatic driven micromotor produced by LIGA
process is shown in figure. All three components – the rotor (center gear),
the stator, and the torque transmission gear are made of nickel. The toothed
rotor’s dia is of 700 microns and the gear is 250 microns dia. The gap
between rotor and stator is 4 microns. The height of the unit is 120 microns.
Successful Devices
13S.Meenatchisundaram, Department of Instrumentation & Control Engineering, MIT, Manipal

14. Micro Turbine: A microturbine was produced to generate power made of
nickel in 1993 as shown in figure. The unit height is 150 microns and a
maximum rotational speed 1,50,000 revolutions per minute with a lifetime
up to 100 million rotations.
Successful Devices
14S.Meenatchisundaram, Department of Instrumentation & Control Engineering, MIT, Manipal

15. Micro Switch: These components are extensively used for high speed
signal transmission. Micro optical switches are used to regulate incident
light from optical fibers to appropriate receiving optical fibers.
Successful Devices
15S.Meenatchisundaram, Department of Instrumentation & Control Engineering, MIT, Manipal

16. Principle science and engineering disciplines involved in micro system
design and manufacture is shown in the figure.
Principle Science
16S.Meenatchisundaram, Department of Instrumentation & Control Engineering, MIT, Manipal

17. Animation Demo
17S.Meenatchisundaram, Department of Instrumentation & Control Engineering, MIT, Manipal
3D_stack Accelerometer
Demo
Accelerometer
Demo
DLP Demo
RF Switch
Demo
Coventorware
Demo
Cantilever Switch
Demo