Micro Electro Mechanical Systems (MEMS) Class Materials - Lecture 02

Department of Instrumentation & Control Engineering, MIT, Manipal

Lecture #02

MEMS – An Overview

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Department of Instrumentation & Control Engineering, MIT, Manipal

Contents

1. Advantages and limitations

2. Applications

3. Visual Examples of MEMS Devices

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S.Meenatchisundaram, Department of Instrumentation & Control Engineering, MIT, Manipal

Advantages and limitations

Advantages:

� 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.

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� 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.

� Higher surface to volume ratio.

Limitations:

� Friction is greater than inertia. Capillary, electrostatic and atomic forces as

well as stiction at a micro-level can be significant.

� Heat dissipation is greater than heat storage and consequently thermal

transport properties could be a problem or, conversely, a great benefit.

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� Fluidic or mass transport properties are extremely important. Tiny flow spaces

are prone to blockages but can conversely regulate fluid movement.

� Material properties (Young’s modulus, Poisson’s ratio, grain structure) and

mechanical theory (residual stress, wear and fatigue etc.) may be size dependent.

� Integration with on-chip circuitry is complex and device/domain specific. Lab-

on-a-chip systems components may not scale down comparably.

� Miniature device packaging and testing is not straightforward. Certain MEMS

sensors require environmental access as well as protection from other

external influences.

� Testing is not rapid and is expensive in comparison with conventional IC

devices.

� Cost – for the success of a MEMS device, it needs to leverage its IC batch

fabrication resources and be mass-produced. Hence mass-market drivers must

be found to generate the high volume production.5

• Automobile IndustryTire pressure sensor

Engine oil sensor

Combustion sensor

Fuel rail pressure sensor

• SafetyAir Bag Deployment system

Antilock braking systems

Navigation (micro gyroscope)

• Engine and power trainAirflow control

Fuel pump pressure and fuel injection control

Crankshaft positioning

• Health care IndustryDisposable blood pressure transducer (DPT)

Intrauterine pressure sensor (IUP)

Angioplasty pressure sensor

Infusion pump pressure sensor

Sphygmomanometer

Lung capacity meters

Kidney dialysis equipment

• Aerospace IndustryCockpit Instrumentation

Micro gyroscope

Micro satellite

• Industrial ProductsWater level controls

Refrigeration systems

Manufacturing process sensor

• Consumer productsSmart Toys

Sport shoes with automatic cushioning control

Washers with water level controls

Vacuum cleaning

• TelecommunicationsOptical switching and fiber-optic couplings

RF switches

Tunable resonators

Applications

6S.Meenatchisundaram, Department of Instrumentation & Control Engineering, MIT, Manipal

Applications


Visual Examples


Accelerometers

Visual Examples


Micro Flying Robot

Visual Examples


World’s Smallest Car

Visual Examples


Visual Examples


World’s Smallest Guitar

Visual Examples


Pressure Sensors

Visual Examples


LIGAGerman words for lithography, electroplating, and molding - High Aspect Ratio

Micromachining Technique

Low cost coplanar waveguide

Visual Examples


Micro Electro Mechanical Systems (MEMS) Class Materials - Lecture 02

Engineering

Transcript of Micro Electro Mechanical Systems (MEMS) Class Materials - Lecture 02