MEMS an overview and application

An overview and applications

Presented by:

Khatib Minajoddin Alimoddin

TE (Mech)

UCOER

MEMS: Micro Electro Mechanical System

Combination of mechanical function (sensing, motion,

heating) and electric function (switching, deciding) to

produce component on micro scale.

Thickness of component is less than

human hair…

1889-Discovery of semiconductor

1958-discovery of IC by Jack Kilby

1974-Ultra Large Scale Integration Technology

(ULSI)

1988-Micromachining Technology discovered

Mechatronics does not bother about size of component

Size of component in MEMS limited to ‘Micro scale

only’

MEMS can combine with number of branches

like BIO, COMPUTER, ROBOTICS etc.

Sensor: Device experience external change in

parameter

Transducer: Energy convertor

Actuator: Other form of energy to mechanical

convertor

Semiconductor:

Silicon, polonium

Polymer:

Metal:

Gold, nickel, silver, titanium etc.

High reliability

Deposited by electroplating, evaporation

Three basic steps are:

Deposition process

Photo-lithography

Etching

Deposition of thin film of material on substrates Thickness of film from nanometer to 100 millimeter

Two types are:

1)Physical deposition process

Physical vapour deposition

Casting

2)Chemical deposition process

Chemical vapour deposition

Electro deposition

Thermal oxidation

Defining the shape of micro machine

Shape to the substrate given by image transfer

by Ultraviolet Light

Two types are:

1)Positive resist transfer

2)Negative resist transfer

Etching process

• Formation of functional MEMS structure on

substrate

Two types are:

1)Dry etching

Material dissolved in chemical solution by reactive

ion or vapour phase etchant

2)Wet etching

Material is dissolved in chemical solution itself

Joining of different component together to function as single

unit

Some technique are:

Bulk micromachining

Surface micromachining

Micro molding

3-d micro machined structure

Linear rack gear reduction drive

Application of MEMS

Bio-MEMS

Lab-on-chip

Micro total analysis

Microfluidics

Micro drug

delivery

Smart pill

Accelerometer

Pressure sensor

MEMS gyroscope

Micro engine

Advanced memory

Devices

Application

ADVANTAGES DISADVANTAGES

1)Minimize energy and

material used in

manufacturing

1)Farm establishment require

huge investment

2)Improved reproducibility 2)Very complex design

procedure

3)Cost and performance

advantages

3)Prior knowledge is needed

for integration of MEMS

devices

4)Higher accuracy, sensitivity,

selectivity

4)Market value of component

are high

MEMS application will be driven by enabling higher

functionality

Combining different areas of research

i.e. Bio MEMS, microfludics, NEMS ,etc

Future product involve higher level of electro

mechanical product with complex integration

and more intimate interaction with physical world

Online Resources BSAC http://www-bsac.eecs.berkeley.edu/

DARPA MTO http://www.darpa.mil/mto/

IEEE Explore http://ieeexplore.ieee.org/Explore/DynWel.jsp

Introduction to Microengineeringhttp://www.dbanks.demon.co.uk/ueng/

MEMS Clearinghouse http://www.memsnet.org/

MEMS Exchange http://www.mems-exchange.org/

MEMS Industry Group http://www.memsindustrygroup.org/

Journals Journal of Micromechanical Systems

journal of Micromechanics and Micro engineering

Micromachine Devices

Sensors Magazine