MEMS technology consist of micro electronic elements actuators, sensors and mechanical structures built onto a substrate which is usually “Silicon”. They are developed using microfabrication techniques : deposition, patterning, etching. The most common forms of MEMS production are : Bulk micromachine, surface micromachine etc. The benefits of this small scale integrated device brings the technology of nanometers to a vast no. of devices. Micro-Electro-Mechanical Systems, or MEMS, is a technology that in its most general form can be defined as miniaturized mechanical and electro-mechanical elements that are made using the techniques of micro fabrication. The critical physical dimensions of MEMS devices can vary from well below one micron on the lower end of the dimensional spectrum, all the way to several millimeters.

1. Instrumentation Department

2. Presented By :
 MOHIT SINGH RAJPUT

3.  MEMS technology consist of micro electronic
elements actuators, sensors and mechanical
structures built onto a substrate which is usually
“Silicon”. They are developed using
microfabrication techniques : deposition,
patterning, etching.
 The most common forms of MEMS production are
:
 Bulk micromachine, surface micromachine etc.
The benefits of this small scale integrated device
brings the technology of nanometers to a vast
no. of devices.

4.  Micro-Electro-Mechanical Systems, or MEMS, is a technology that in its most
general form can be defined as miniaturized mechanical and electro-
mechanical elements that are made using the techniques of micro fabrication.
The critical physical dimensions of MEMS devices can vary from well below
one micron on the lower end of the dimensional spectrum, all the way to several
millimeters. Likewise, the types of MEMS devices can vary from relatively
simple structures having no moving elements, to extremely complex
electromechanical systems with multiple moving elements under the control of
integrated microelectronics. The one main criterion of MEMS is that there are
at least some elements having some sort of mechanical functionality whether or
not these elements can move. The term used to define MEMS varies in different
parts of the world. In the United States they are predominantly called MEMS;
while in some other parts of the world they are called “Microsystems
Technology” or “micro machined devices”. microsensors and microactuator
are appropriately categorized as “transducers”, which are defined as devices
that convert energy from one form to another. In the case of microsensors, the
device typically converts a measured mechanical signal into an electrical signal.

5.  What are MEMS ?
 Components of MEMS
 Fabrication of MEMS
 Applications of MEMS
 Benefits of MEMS

7.  Micro-Electro-Mechanical Systems, or MEMS, is a technology
that in its most general form can be defined as miniaturized
mechanical and electro-mechanical elements that are made
using the techniques of microfabrication.
 The critical physical dimensions of MEMS devices can vary
from well below one micron on the lower end of the
dimensional spectrum, all the way to several millimeters.
Likewise, the types of MEMS devices can vary from relatively
simple structures having no moving elements, to extremely
complex electromechanical systems with multiple moving
elements under the control of integrated microelectronics.
 The one main criterion of MEMS is that there are at least
some elements having some sort of mechanical functionality
whether or not these elements can move. The term used to
define MEMS varies in different parts of the world.

9. Micro Sensor Micro Actuator
Micro Electronic Micro Structure
MEMS

10. 1. MicroElectronics
 The microelectronics of a MEMS are very similar to
chips as we think of them today. The
microelectronics act as the "brain" of the system. It
receives data, processes it, and makes decisions.
The data received comes from the microsensors in
the MEMS.
2. MicroSensors
 The microsensors act as the arms, eyes, nose, etc.
They constantly gather data from the surrounding
environment and pass this information on to the
microelectronics for processing. These sensors can
monitor mechanical, thermal, biological, chemical,
optical and magnetic readings from the
surrounding environment.

11. 3. MicroActuators
 A microactuator acts as a switch or a trigger to activate an
external device. As the microelectronics is processing the
data received from the microsensors, it is making decisions
on what to do based on this data. Sometimes the decision will
involve activatin3g an external device. If this decision is
reached, the micrelectronics will tell the microactuator to
activate this device.
4. MicroStructures
 Due to the increase in technology for micromachining,
extremely small structrures can be built onto the surface of a
chip. These tiny structures are called micro structures and are
actually built right into the silicon of the MEMS. Among other
things, these microstructures can be used as valves to control
the flow of a substance or as very small filters.

12. Deposition:
• deposit thin film of material (mask) anywhere between a few
nm to 100 micrometers onto substrate
• physical: material placed onto substrate, techniques include
sputtering and evaporation
• chemical: stream of source gas reacts on substrate to grow
product, techniques include chemical vapor deposition and
atomic layer deposition
• substrates: silicon, glass, quartz
• thin films:polysilicon, silicon
dioxide, silicon nitride, metals,
polymers

14. There are three types of technologies for
manufacturing "MEMS" which are as follows :
 Bulk Micromachining
 Surface Micromachining
 High Aspect Ratio (HAR) Silicon
Micromachining

15.  Both bulk and surface silicon micromachining are used in the industrial
production of sensors, ink-jet nozzles, and other devices. But in many
cases the distinction between these two has diminished. A new etching
technology, deep reactive-ion etching, has made it possible to combine
good performance typical of bulk micromachining with comb structures
and in-plane operation typical of surface micromachining .While it is
common in surface micromachining to have structural layer thickness in
the range of 2 µm, in HAR silicon micromachining the thickness can be
from 10 to 100 µm.The materials commonly used in HAR silicon
micromachining are thick polycrystalline silicon, known as epi-poly, and
bonded silicon-on-insulator (SOI) wafers although processes for bulk
silicon wafer also have been created (SCREAM). Bonding a second
wafer by glass frit bonding, anodic bonding or alloy bonding is used to
protect the MEMS structures. Integrated circuits are typically not
combined with HAR silicon micromachining.

16.  MEMS technologies are widely used in almost
every field such as physical , bio-medical and
chemical fields.
 Besides these "MEMS" are used in automobiles
industry and are now becoming the face of
Bio-medical engineering.
 The following are discussed below :

18.  MEMS has changed the way of medical science by a
rapid development in bio-medial industry . Some
are mentioned below :
 MEMS Pressure Sensor .
 MEMS Inertial Sensor .
 MEMS Machined Needles .
 MEMS Surgical Tools .
 Micro-fluids For Drug Delivery.
 Micro-fluid For Diagnostics .

19. Applications
Inertial
Sensor
Surgical
Tools
Micro
Needles
Pressure
Sensor

20. MEMS Inertial
Sensors .
MEMS accelerometers are used in
defibrillators and pacemakers. Some
patients exhibit unusually fast or chaotic
heart beats and thus are at a high risk of
cardiac arrest or a heart attack. An
implantable defibrillator restores a
normal heart rhythm by providing
electrical shocks to the heart during
abnormal conditions. Some peoples’
hearts beat too slowly this may be
related to the natural aging condition . A
pacemaker maintains a proper heart beat
by transmitting electrical impulses to the
heart. Conventional pacemakers were
fixed rate. Modern pacemakers employ
MEMS accelerometers and are capable of
adjusting heart rate in accordance with
the patient’s physical activity. Medtronic
is a leading manufacturer of MEMS based
defibrillators and pacemakers

21.  Much smaller area
 Cheaper than alternatives
 In medical market, that means disposable
 Can be integrated with electronics (system on one chip)
 Speed:
 Lower thermal time constant
 Rapid response times(high frequency)
 Power consumption:
 low actuation energy
 low heating power
Imperfect fabrication techniques
 Difficult to design on micro scales