MEMS (micro-electro-mechanical systems) are microscopic devices and integrated systems that combine electrical and mechanical components between 1-100 micrometers in size. They integrate sensors, actuators and electronics on a common silicon substrate through microfabrication technology. MEMS originated in the 1980s and are now used in automotive, biomedical, industrial and consumer applications. Some key advantages of MEMS include lower manufacturing costs, reduced size, and lower power consumption compared to macro-scale devices. Challenges include developing robust packaging and manufacturing processes for commercialization.

1. MICRO-ELECTRO-MECHANICAL
SYSTEMS
KAUSHAL PANT BSc, BA, B Tech

2. AIM
TO GIVE AN OVERVIEW ABOUT
MEMS

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

4. • Technology 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

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

7. ON SIZE AND SCALE

9. 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).

10. HISTORY
• 1947 : Telephone by Bell
• 1958 : First IC (Ge).01 Transistor, 03 Resistors, 01
Capacitor.
• 1959: Richard Feynman, California “There’s Plenty of
Room at the Bottom”. $1000 for car 1/64th of an inch.
• 1961: First si pressure sensor demonstrated.
• 1967: Invention of surface micromachining.
• 1970: First silicon accelerometer demonstrated.
• 1979: First micromachined inkjet nozzle.

11. HISTORY
• 1980: First experiments in surface micromachined silicon.
• 1982: Disposable blood pressure transducer and LIGA
• 1988: MEMS was coined ,First MEMS conference.
• 1990: Micromachining towards improving sensors.
• 1992: Multi-User MEMS Process (MUMPS) by DARPA).
• 2001: Triaxis accelerometers appear on the market.
• 2004: TI’s DLP chip sales rose to $900 million.
• 2007: MEMS industry group (MEMS-IG)
• 2017: MEMS devices permeate our lives.

12. SUBTRATES
• Silicon
• Glass
• Polymers
• Metals - Metals like Gold, Ni, Al, Cr, Pl, and Ag
• Ceramics
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13. FABRICATION
13
Basic Process
Deposition Patterning Etching
Chemical
Wet
Dry
Physical
Lithography
Photolithography

14. 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.
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15. FABRICATION
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Photolithography.

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

17. FABRICATION
17
a) Photolithography.

18. 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.

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

20. LIGA
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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

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

22. 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.

23. PACKAGING

24. 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

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

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

27. 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.

28. MEMS IN INDIA
• Jul 2002 first Lab ( IISc & CSI Ltd)
• Microelectronics Group & Suman Mashruwala Micro-
engineering Lab, IIT Bombay
• Fabrication facilities at:
• CEERI Pilani, ITI, BEL in Bangalore, SCL Chandigarh etc.
• Microelectronics Laboratories in close interaction with Indian
industries (BEL, DRDO , ISRO etc)
• MEMS work in Acoustic Sensor & Ultrasound sensors, in
GSLV & PSLV.
• Development of analytic tools and software.

29. CONCLUSION
• Promising technology for the 21st Century.
• Disruptive technology differs significantly from existing
technology.
• Challenges associated with developing manufacturing
processes.
• Automotive industry varied signatures in all fields.
• MEMS has gradually made its way out of research
laboratories and into everyday products.

30. THANK YOU