1. 4 Operation, mechanisms and applications
Workshop
MEMS MOEMS Nano
4 Operation, mechanisms and applications
Ken Gilleo PhD
ET-Trends LLC

2. Motion (actuators) Actuators (“motors”) Electrical (input)
Thermal (usually from electrical)
Photonic (for MOEMS, OE)
Sensors (output); usually electrical signals
Capacitance
Piezoresistive
Resonant beam
Electron tunneling
Photonic
Chemical
Biological/biochemical
POWER
Change/output
is caused by
mechanical
motion/force
TYPES

3. Actuator Classes Electrostatic/capacitive Electromagnetic Thermal
Linear comb drive
Rotary comb drive
Horizontal parallel plates
Electromagnetic
Linear
Rotary
Integrated coils or external field
Permanent or soft magnetic films
Thermal
Bimorph: dissimilar materials
Shape memory alloys
Pneumatic/hydraulic
Mechanical conversions/translations

4. MEMS Engines Electrostatic; very efficient *
Thermal; easy to implement
Electromagnetic, smaller
Pneumatic
Hydraulic
Photoelectric (energy through fiber)
*Surface area is relatively high, mass is very low; surface effects are important

5. Electrostatic (ES)
Charged
Anchor point
shuttle
ES Unit

6. Thermal Engines (T) Expansion High force, moderate displacement
Material, external; inkjet
Bimorph beam - bending
High force, moderate displacement
Frequency limited by conductivity

7. Bimorph Beam (Thermal)
off
Resistive heater
Low CTE on
High CTE

8. Electromagnetic
U of Wisconsin
CalTech

9. MEMS Pumps Actuation Mechanisms Direct Fluidic Actuation Electrostatic
Thermal
Magnetic
Pneumatic
Piezoelectric
Ultrasonic
Direct Fluidic Actuation
Fluidic phase change
Electrohydrodynamic (EOF, electrophoresis, etc)
Direct fluidic actuation mechanisms
Debiotech STMicroelectronics insulin pump
Thermal Inkjet
Bellows: Air Pump

10. Accelerometers, mics, more
Sensors – the #1 Class
Popular for
Accelerometers, mics, more
Capacitance
Piezoresistive
Resonant beam
Electron tunneling
Photonic
Chemical
Biological/biochemical
Many
principles

11. Inertial Sensors (motion)
Accelerometers
Capacitor
Resonant
Multiple axis
Gyroscopes
ADI
JPL
ADI

12. Accelerometer/Gyros Consumer Military Industrial Automotive
Sensing: crash, torque, vibration (well-being)
Navigation; GPS back-up
Active suspension
Consumer
Input device; computer, games, phones
Sports training, medical therapeutic
Alarms; burglar, seismic (earthquake)
Stabilization, camera
Military
Ordnance; guidance, condition, attack warning
Operator input/control
Aiming; gun, camera (stabilization)
Industrial
Sensing: vibration, tilt, direction, rate
Stabilization
Monitoring
Robotics; position, contact, feedback, etc.
ADI

13. INERTIAL Dual-Axis Gyroscope Resonant Accelerometers
Now owned by ADI
INERTIAL
Dual-Axis Gyroscope
Resonant
Accelerometers
3-Axis Accelerometer
Z-Axis Gyroscope

14. Accelerometer Applications
Automotive
Consumer
Industrial/Scientific/Military
ABS/Antiskid
Airbag Deployment
Anti-Rollover Detection
Battery Disconnect
Crash Alerting
Dynamic Suspension
Dynamic Ride Control
Dynamic Cruise Control
Electronic Park Brake
Fleet Monitoring
Fuel Shutoff
Headlight Leveling
Inertial Navigation – backup
Misfire Detection
Security/Antitheft
Seatbelt Tensioning
Stability Systems
Tilt Sensing
Tire Motion
Tire Pressure
Transmission
Monitor Vehicle Performance
Active Subwoofers
Ambulatory Training
Appliances
Binoculars
Blood Pressure Monitor
Camcorders Stabilizer
Digital Pens
Digital Cameras Stabilizer
Disk Drive Monitoring
Game Controllers Handheld GPS
Head Tracking Inertial Navigation
Laptop Anti-Theft
Laptop Drop Detection
Joysticks Mouse - 3D
Out-of-Balance Medical Devices
Sleep Monitor Pedometers
Sports Training – golf
Sports Training – fly cast
Sports Training – batting
Tilt Sensing
Virtual Reality I/O
Wearable Computing I/O
Antenna Alignment
Antenna Switches
Construction Leveling
Machine
Health Equipment
Tilt Sensing
Fork Lift Positioning
Marine Navigation
Platform Leveling
Seat Damping
Seismic
Gas Shutoff
Satellite Dish Alignment
Satellite Gyroscopes
Ship mechanical monitoring
Shock Sensing
UAVs
UMVs
Vibration Monitoring

15. Automotive Pressure Sensors Pressure Sensors Fuel Tire Manifold
Fuel Pressure Sensor
Injector Pressure Sensor
Automotive
Pressure Sensors
Pressure Sensors
Fuel
Tire
Manifold
Injector AC
Mass air
Break
Fuel vapor
Oil
AC Pressure Sensor

16. Pressure Sensors Transducers Piezoresistor Capacitor Resonant beam
Internal ref. pressure
Thin diaphragm
Transducer
Transducers
Piezoresistor
Capacitor
Resonant beam
Resonating beam (F1)
Resonating beam is now under tension; (F2)
Vacuum

17. Chemical Sensors i Chem-FET Heater
Reactive surface adsorbs gases i
Heater
Readily detects H2, CO, Alcohols, Hydrocarbons
Chem-sensor gate; adsorbing metal like Pd
Adsorption lowers threshold voltage since a dipole is induced.
Chem-FET Vs Vd

18. Mechanical Transfer Gears Wheels Levers Rackets
Shuttles; walking beams
Hinge & lock
Articulated beams

19. Power Device Classes Extractors using ambient energy
Converters: energy-1 energy-2
Relays for power (not signal)
Power controllers (beyond relays)
Generators using fuel
1. Uses waste energy, 2. Uses generated energy

20. Power Extractors Typically utilize machine mechanical vibrations C1 C2
Changing capacitor plate spacing generates power; reverse damper. C2
C2 an be replaced with a magnet.
Machines produce mostly 1 KHz to 5 KHz vibrations

21. 10 to 100 watts 100 K to 1-million RPM
Power MEMS
Chemical fuel to:
Mechanical rotation, reciprocation, etc.
Fluid or gas pumping force
Electrical (fuel cell)
Thrust; rocket
Mechanical Electrical (turbo-generator)
Photonic to electrical (really just a converter)
Mechanical, electrical to chemical (battery)
10 to 100 watts 100 K to million RPM

22. Gas Turbine

23. TI MOEMS: DLP on off on on on on off on Over 8-million parts
Ref. “Digital Light Processing TM for High-Brightness, High-Resolution Applications” Larry J. Hornbeck, Ti.com

24. 1,400,000 mirrors in one module Texas Instruments DLPTM
animation by kbg

25. Session Summary Most MEMS are directly electrically powered
Electrostatic is simplest; very popular
Bimorph is ideal for no/low wear beams
Many kinds of mechanical transfer
Sensors will remain largest market
Reliability issues on some, but not all MEMS