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

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

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

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

Electrostatic (ES) Charged Anchor point shuttle ES Unit

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

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

Electromagnetic U of Wisconsin CalTech

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

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

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

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

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

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

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

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

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

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

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

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

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 1-million RPM

Gas Turbine

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

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

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