Micro-electro-mechanical systems (MEMS) are miniature devices that combine electrical and mechanical components. MEMS components range in size from 1-100 micrometers and are fabricated using microfabrication techniques. MEMS devices can sense and control the physical world on small scales and have applications in areas like sensors, actuators, and biomedical devices. The document discusses MEMS fabrication techniques including deposition, patterning, etching, and packaging and provides examples of common MEMS devices and applications.

1. MICRO-ELECTRO-MECHANICAL
SYSTEMS

2. PREVIEW
• MEMS Introduction
• Fabrication and Basic techniques
• Applications
• Advantages & Disadvantages
• Future Trends
• MEMS in India
• Conclusion
• References

3. • T
echnology of Microscopic devices & miniaturized
Integrated systems
• Components 1 and 100 micrometres in size.
• Devices 20 micrometres to a millimetre (i.e. 0.02 to
1.0 mm)
• Micro-sized components assembled & working together
as a system
INTRODUCTION

4. Photo: http://
What are MEMS?
Micro-Electro-Mechanical Systems (MEMS)
• Miniaturized mechanical and electro-mechanical
elements (devices and structures)
• Sizes range from millimeters to fractions of
micrometers
• Some parts of the device have some sort of
mechanical functionality
• A.K.A. Microsystems Technology or
Micromachined Devices

5. • Technique of combining Electrical & Mechanical disiciplines.
• System of miniature dimensions.
• Micro fabrication technologies.
• Both sense on Micro scale effect on Macro scale
• Control the environment.
• Potential to effect all of our lives
5

6. Process flow
• Design
– Numerical
• Coventorware, Intellisuite, COMSOL, ANSYS etc,.
– Analytical
• Fabrication
• Assembling
• Packaging
• Testing
– At die level
– At packaging level
6

7. WHAT IS MEMS?
6
• Micro-electronics - Brain of the system.
• Micro-sensors
• Micro-actuator
• Micro-structure
- Arms ,eyes, nose etc.
- Switch or trigger.
-Micromachining

8. WHY MICROMACHINE
• Minimize energy and mtrls use in manufacturing.
• Integration with electronics, reduction of power budget.
• Faster devices, incr selectivity and sensitivity.
• Cost/Performance advantages.
• Improved reproducibility (batch fabrication).
• Improved accuracy and reliability.
• Minimally invasive (e.g. pill camera).

9. SUBTRATES
• Silicon
• Glass
• Polymers
• Metals - Metals like Gold, Ni, Al, Cr, Pl, and Ag
• Ceramics 12

10. 10
Why Silicon?
• Not only a semiconductor
• Very good structural material comparable with that of steel
– Young’s modulus
– Poisson’s ratio
– Yield strength
• Derives fabrication principles from well established Si based
IC technology
• Electronic circuits
– Solid and compact
• MEMS structures
– holes, cavity, channels, cantilevers, membranes, etc,

11. FABRICATION
13
Basic Process
Deposition Patterning Etching
Chemical
Wet
Dry
Physical
Lithography
Photolithography

12. BASIC PROCESS OF FABRICATION
• Deposition
– Deposition that happen because of a Chemical reaction or
Physical reaction.
• Patterning
– Transfer to a photosensitive material, exposure to UV light.
– Developed in solution after exposure to UV.
– Material Etch away.
• Etching
– Strong acid to cut into the unprotected parts of a metal
surface to create a design.
– Two classes :
• Wet Etching
• Dry Etching.
14

13. FABRICATION
15
Photolithography.

14. FABRICATION
16
2. Etching.
a) Dry
b) Wet

15. FABRICATION
17
a) Photolithography.

16. DEPOSITION
a) Physical Vapour Deposition.
• Thin films one atom (or molecule)
• Physical coating.
• Deposition of aluminium or gold conductors.
b) Chemical Vapour Deposition.
• Volatile precursors on wafer react and/or decompose
• High-purity, high-performance solid materials.

17. MEMS MANUFACTURING
TECHNOLOGY
19
a) Bulk Micromachining.
b) Surface Micromachining.
c) High Aspect Ratio (HAR) Si Micromachining.
•
•
LIGA
SLIGA

18. LIGA
20
Lithographie (Lithography), Galvanoformung (Electroforming), &
Abformung (Molding)
• Additive Process
• HARMST-High Aspect Ratio Microstructure Technology.
• Precise dimensions and good surface roughness.
• Output- Finished parts, molds, or stamps
•SLIGA (Sacrificial LIGA). lower manufacturing
infrastructures

19. LIGA
Photo sensitive Material PMMA –Poly methyl metha crylate

20. PACKAGING
a) Protection & robust to operating environment.
b) Access and connections to physical domain.
c) Minimize electrical interference.
d) Dissipate heat for high operating temperatures.
e) Minimize stress from external loading.
f) Electric Power handling without signal disruption.

21. PACKAGING

22. MEMS APPLICATION
MICRO NANO
WORLD
MEMS IN DEF
BIO MEMS
MICRO PROBING
(STF,AFM)
PRESSURE
,FORCE,INTERTIAL
,SOUNDS
MICRO MAGNETICS
RF MEMS
MICRO FLUIDICS MICRO IT

23. MEMS ADVANTAGES
IC COMPATIBLE
LOW COST
RUGGEDNESS
SMALLER
BATCH FABRICATION
MINIATURIZATION
LOW POWER CONSUMPTION
HIGHER PERFORMANCE

24. DISADVANTAGES
capabilities and
manufacturing
• Impossible to transfer of Power impossible.
• Poly-Si (a brittle material), Cannot be load and force limitations.
• Disruptive technology, need different
competencies.
• Scaling, Packaging and Testing Issues.
• Challenges associated with developing
processes.
• Critical technological bottlenecks, economic feasibility.
• Time & expense.

25. MEMS Sensors
• Turn physical phenomena into measurable
electrical signals
• Most (if not all) incorporate
circuitry/components to interpret electrical
signals
• Some have no moving parts

26. MEMS Sensors - Accelerometer

27. MEMS Sensors - Accelerometer

28. MEMS Sensors - Accelerometer

29. MEMS Sensors - Accelerometer
Analog Output
Accelerometer Module
$2.70

30. MEMS Devices
• Some are just scaled down versions of other
systems
• Use electric or electromagnetic principles to
control mechanical effects
• Commonly used in groups rather than
individually

31. Some MEMS Applications
Microchain Drive
(Microchain &
Gears)

32. FUTURE OF MEMS
Challenges
• Access to Foundries.
• Design Simulation & Modelling
• Packaging and Testing
• Standardization
• Education and Training.
• Micro-sized objects allow us to go places where no objects
have gone before.