Download Mems - UTK-EECS

Textbook:
MEMS and Microsystems,
MEMS (Meicro-electro-mechanical
Systems) and Microsystems:
--Design, Manufacture, and Nanoscale Engineering,
by Tai-Ran Hsu, 2nd edition, John Wiley & Sons, 2008
and class handouts
---Design, Manufacture and Nanoscale
Engineering
Reference books:
Micromachined Transducers Sourcebook, by
G.T.A. Kovacs, McGraw-Hill
BioMEMS and Medical Microdevices, by
Saliterman, Wiley-Interscience
Instructor: Dr. Jie Wu
Dept. of Electrical Engineering and Computer Science
Tentative schedule:
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Chapter 2 Principles, 11.9, 4.2 and 4.3
2.6 Microfluidics
Chapter 5 Thermofluid Engineering
3.8 Electrokinetics
Midterm
Chapter 7 Materials for MEMS
Chapter 3 Engineering Science
Chapter 8 Microfabrication
Chapter 9 Micromachining
Nanotechnology if time permits.
3 weeks
3 weeks
1 week
MEMS describes system functions which often include optical,
mechanical or fluidic functions.
3 weeks
2 weeks
MST [EU] or Micromachines [JP]
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Grading: 30% about 6 homework with additional unannounced
quizzes. 15% paper reports. 20% Midterm. 35% Final.
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No makeup quizzes and exams.
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The Start of Micro-Era
Significant technological development towards miniaturization was initiated with
the invention of transistors by three Nobel Laureates, W. Schockley, J. Bardeen
and W.H. Brattain of Bell Laboratories in 1947.
This crucial invention led to the development of the concept of integrated circuits
(IC) in 1955, and the production of the first IC three years later by Jack Kilby of
Texas Instruments. ICs have made possible for miniaturization of many devices
and engineering systems in the last 50 years. The invention of transistors is thus
regarded as the beginning of the 3rd Industrial Revolution in human civilization.
A way of making things
– Leverage on existing infrastructure of IC fabrication tools
– Prototype on mass-production fabrication tools
Co-location of sense, compute, actuate, control, communicate, power
– Increase performance and decrease cost
– Integrate an increased number of fabrication technologies
Microscale control of electrical, thermal, fluid, magnetic, optical, and mass flux
There's Plenty of Room at the Bottom
An Invitation to Enter a New Field of Physics
“People tell me about miniaturization, and how far it has progressed
today. They tell me about electric motors that are the size of the nail
on your small finger. And there is a device on the market, they tell
me, by which you can write the Lord's Prayer on the head of a pin.
But that's nothing; that's the most primitive, halting step in the
direction I intend to discuss. It is a staggeringly small world that is
below. In the year 2000, when they look back at this age, they will
wonder why it was not until the year 1960 that anybody began
seriously to move in this direction. Why cannot we write the entire 24
volumes of the Encyclopedia Brittanica on the head of a pin?”
— Richard Feynman, Nobel Prize winner in physics
The first germanium bipolar transistor.
Roughly 50 years later, electronics account
for 10% (4 trillion dollars) of the world GDP.
Dec. 29, 1959, at the APS annual meeting, Caltech
This goal requires patterning at the 10 nanometer scale.
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Vision of Micro-Systems
a reduction of
25,000 times
from its
standard print
The Nippondenso Micro-Car (1994)
Nippondenso's microcar was produced with
precision machining and semiconductor
process technologies ... the intention was to
demonstrate the abilities and future potential
of the micro processing technology by
manufacturing a car which is one onethousandth the size of an actual car... The
latest model has a micro-motor 1 mm in
diameter. With power supplied by a 25
micron copper wire, the car runs smoothly at
a speed of about 1 cm/s with 3 V voltage and
20 mA current. The use of a shell body
construction as shown in Photo 1 reduced the
weight and allowed accommodation of the
driving gears. The body is made by
electroless nickel plating and sacrificial layer
etching, and the surface is gold plated. It is
30 microns thick yet strong enough to be
picked up by the fingers."
250-microgram
2000-rpm motor
consisted of 13
separate parts
Miniaturization of Digital Computers
- A remarkable case of miniaturization!
Miniaturization Makes Engineering Sense!!!
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Small systems tend to move or stop more quickly due
to low mechanical inertia. It is thus ideal for precision
movements and for rapid actuation.
Miniaturized systems encounter less thermal distortion
and mechanical vibration due to low mass.
Miniaturized devices are particularly suited for
biomedical and aerospace applications due to their
minute sizes and weight.
Small systems have higher dimensional stability at
high temperature due to low thermal expansion.
Smaller size of the systems means less space
requirements. This allows the packaging of more
functional components in a single device.
Less material requirements mean low cost of
production and transportation.
Ready mass production in batches.
MEMS: dimensional ranges
• Scale: from below 1 μm to
above 1 mm
• Manufacture: batch fabrication
technology
• Function: micro -mechanics, electronics, -fluidics, -optics,
…
• Use existing silicon processing
infrastructure to create micronscale machines.
• Can have many functions,
including sensing, actuation,
and communication.
• Just like microelectronics,
MEMS will permeate our
everyday lives in the coming
decades. Micro cilia array
Any engineering system that performs electrical and mechanical functions
with components in micrometers is a MEMS. (1 μm = 1/10 of human hair)
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Available MEMS products
• MEMS (started ~1960) is now part of our everyday life with products
ranging from airbag accelerometers to digital TV’s. New applications
and research are on-going.
• Microfluidics(started ~1980) associated with analytical
instruments,ink-jet printing and solution based fabrication is now a
full fledged technology. New applications and research are ongoing.
• BioMEMS–integration of machines and biology (including people) is
in a similar state of development to microfluidics. New applications
and research are on-going.
• NEMS (started ~1990) is still in the laboratory, but first applications
are probably not far away (e.g. quantum dots and nanoparticles).
New applications and research are on-going.
MEMS Industries
Micro sensors (acoustic wave, biomedical, chemical,
inertia, optical, pressure, radiation, thermal, etc.)
Micro actuators (valves, pumps and microfluidics;
electrical and optical relays and switches; grippers,
tweezers and tongs; linear and rotary motors, etc.)
Read/write heads in computer storage systems.
Inkjet printer heads.
Micro devices components (palm-top reconnaissance
aircrafts, toy cars, etc.)
MEMS Commercial Applications
• Inertial Measurement
– Accelerometers, Rate Sensors, Vibration Sensors
– TI, Sarcos, Boeing, ADI, EG&G IC Sensors, AMMi, Motorola, Delco, Breed, Systron Donner
• Microfluidics and Chemical Testing/Processing
– Gene Chip, Lab on Chip, Chemical Sensors, Flow Controllers, Micronozzles, Microvalves
– Battelle, Sarnoff, Microcosm, ISSYS, Berkeley MicroInstruments, Redwood, TiNi Alloy,
Affymetrix, EG&G IC Sensors, Motorola, Hewlett Packard, TI, Xerox, Canon, Epson
• Optical MEMS (MOEMS)
– Displays, Optical Switches, Adaptive Optics
– Tanner, SDL, GE, Sarnoff, Northrop- Grumman, Westinghouse, Interscience, SRI, CoreTek,
Lucent, Iridigm, Silicon Light Machines, TI, MEMS Optical, Honeywell
• Pressure Measurement
– Pressure Sensors for Automotive, Medical, and Industrial Applications
– Goodyear, Delco, Motorola, Ford, EG&G IC Sensors, Lucas NovaSensor, Siemens, TI
• RF Technology
– RF switches, Filters, Capacitors, Inductors, Antennas, Phase Shifters, Scanned Apertures
– Rockwell, Hughes, ADI, Raytheon, TI, Aether
• Other
– Actuators, Microrelays, Humidity Sensors, Data Storage, Strain Sensors, Microsatellite
Components
MEMS Market
Successful MEMS Products
MEMS market: The MEMS market is
expanding quickly, and expected to triple
within 4 years. When much of the MEMS
market so far has come from the
automotive industry, experts see the
share of Bio-MEMS as emerging market
with a market share currently around
16%
Market Analysis [J. Bryzek, 1998]
• Applications include pressure sensors, inertial sensors, fluidics, data
storage, displays, biochips, communication
• Total MEMS market
1995: $1.4B (non-sensor $30M)
2005: $6.7B (non-sensor $3.4B)
• Automotive industry: manifold air pressure sensor, air bag sensor
(accelerometer with self-test)
• TI digital mirror display (DMD)
video projection system (development cost ~ $1B)
• Inkjet nozzles (HP, Canon, Lexmark)
up to 1600 x 1600 resolution (~ 30M units per year)
Texas Instruments
digital light projector
Analog Devices
accelerometer
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TI DMD Light Switch
•Each light switch has an
aluminum mirror (16 µm
square) that can reflect
light in two directions
•Rotation of the mirror
occurs from an
electrostatic attraction
between the mirror and
underlying memory cell
•System occupies 90% of
projected image –mirrors
separated by only 1 µm
Neuroprosthetics
BioMEMS
• Biological and chemical systems ranging from cellular to
molecular level
• Biological entities (cells, proteins, DNA)
• Techniques and materials to interface the biological and
synthetic world
• Characterization of such hybrid bioelectronic systems
Drug Delivery
Medtronics
Lab on a chip
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Lab Chip - commercialized
• Nanogen
– Chip based assays, on chip DNA hybridization and optical detection
• Affymetrix
– Chip based assays, on chip DNA hybridization and optical detection
• Cepheid
– DNA detection on a micro-scale for diagnostic, military, and food
safety applications
Affymetrix Gene Chip
• Motorola
– Now has a bio-chip division
Fluidigm chip
• HP/Caliper
– Chip based capillary electrophoresis
Caliper Lab-on-a-Chip
Enabling Technologies for Miniaturization
Enabling Technologies for Miniaturization
Top-Down: Photolithography
• Top-down: Chisel away material to make
micro- nano-scale objects
• Bottom-up: Assemble nanoscale objects
out of even smaller units (e.g., atoms and
molecules)
• Ultimate Goal: Dial in the properties that
you want by designing and building at the
scale of nature (i.e., the nanoscale)
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Sandia gears
AFM probe
MEMS go beyond standard
microelectronics manufacturing
The complex geometry of these minute MEMS components can only be produced
by various physical-chemical processes – the microfabrication techniques originally
developed for producing integrated circuit (IC) components.
Microelectronics
Conventional and new semiconductor processing technology modules are used.
– Etching, Deposition, Photolithography, Oxidation, Epitaxy, Plating, etc.
– Deep RIE, Thick Plating, electro discharge machining, …
Microsystems (silicon based)
Primarily 2-dimensional structures
Complex 3-dimensional structure
Stationary structures
May involve moving components
Transmit electricity for specific electrical functions
Perform a great variety of specific biological, chemical,
electromechanical and optical functions
IC die is protected from contacting media
Delicate components are interfaced with working media
Packaging technology is relatively well established
Packaging technology is at the infant stage
Mature IC design methodologies
Lack of engineering design methodology and standards
Industrial standards available
No industrial standard to follow in design, material
selections, fabrication processes and packaging
Mass production
Batch production, or on customer-need basis
Fabrication techniques are proven and well documented
Many microfabrication techniques are used for
production, but with no standard procedures
Use single crystal silicon dies, silicon compounds, ceramics
and plastic materials
Use single crystal silicon dies and few other materials,
e.g. GaAs, quartz, polymers, ceramics and metals
Fewer components to be assembled
Many more components to be assembled
Complex patterns with high density of electrical circuitry
over substrates
Simpler patterns over substrates with simpler electrical
circuitry
Large number of electrical feed-through and leads
Fewer electrical feed-through and leads
Manufacturing techniques are proven and well documented
Distinct manufacturing techniques
Primarily involves electrical and chemical engineering
Involves all disciplines of science and engineering
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