Transcript
www.tln.co.in
TLN Technology Leads Nation
CONTENTS 1. Overview of MEMS technology 2. History of MEMS technology 3. Miniaturization 4. Scaling laws 4.1. Scaling in Geometry 4.2. Scaling in Rigid-Body Dynamics 4.3. Scaling in Electro Static Forces 4.4. Scaling in Electro Magnetic Forces 4.5. Scaling in Electricity 4.6. Scaling in Fluid Mechanics 4.7. Scaling in Heat Transfer
5. Working Principle of MEMS 5.1. Micro Sensors 5.2. Actuators
6. Examples of MEMS devices 7. Materials used in MEMS Fabrication 8. Microfabrication Processes 8.1. Photolithography 8.2. Ion implantation 8.3. Diffusion 8.4. Oxidation 8.5. Chemical vapor deposition 8.6. Physical vapor deposition (Sputtering) 8.7. Deposition by expitaxy 8.8. Etching
9. Fabrication Methods 9.1. Bulk Micromanufacturing 9.2. Surface Micromanufacturing 9.3. LIGA Process
10. Design and simulation using FEM tools 11. Applications
www.tln.co.in
TLN Technology Leads Nation
1. Overview of MEMS technology
Creation of 3-dimentional structures using integrated circuits fabrication techniques and special micromachining processes. Typically done on silicon or glass(SIO2) wafers. MEMS merge at Nano scale in to Nano Electro Mechanical Systems (NEMS) & Nano technology. MEMS are made up of components between 1 to 100 micrometer in size.
2. History of MEMS technology
MEMS word introduced in 1986 i.e. in proposal submitted to DARPA (Defense Advanced research project agency) by the center for engineering design university of UTAH. Thomas Edison’s first successful light bulb model done in December 1879 at Menlo park. In 1904, British scientist John Ambrose Fleming first showed his device famous as “Fleming Diode” to convert an alternating current signal in to direct current signal. The “Fleming Diode” was base on an effect that Thomas Edison used in light bulb model i.e. “vacuum tube”. From 1904 to 1960 many other inventors tried to improve the “Fleming Diode”, the only one who succeeded was New York inventor Lee De Forest. In 16 December 1947, first time a Solid State Electronic Transistor known as “Point Contact Transistor” developed by John Bardeen and Walter Brattain at bell laboratories led by physicist William Shockly. This group has been working together on experiments and theories of electric field effects in solid state materials, with the aim of replacing “Vacuum Tubes” with a smaller and less power consuming devices. And Silicon oxidation is demonstrated in 1953 in Bell Telephone Laboratories & with this monolithic transistors are implemented. Got Nobel prize in 1956. 1954: Piezoresistive effect in Germanium and Silicon (C.S. Smith), this discovery showed that silicon and germanium could sense air or water pressure better than metal. Many MEMS devices such as strain gauges, pressure sensors, and accelerometers utilize the Piezoresistive Effect in silicon.
TLN Technology Leads Nation
www.tln.co.in
Figure 1: An Example of a Piezoresistive Pressure Sensor [MTTC Pressure Sensor] 1958: First Integrated Circuit (IC) (J.S. Kilby1958 / Robert Noyce1959) Nobel prize in 2000. Miniaturization of electronic circuits is started with this.
Figure 2: Texas Instrument's First Integrated Circuit [Photos Courtesy of Texas Instruments]
The famous lecture “There’s Plenty of Room at Bottom” is by Richard Feynman in 1959, from this it is clear that there is a scope for micro and nano devices to fulfill the future social technical needs. 1959 First silicon pressure sensor demonstrated (Kulite) 1967 Anisotropic deep silicon etching (H.A. Waggener et al.) 1968 Resonant Gate Transistor Patented (Surface Micromachining Process) (H. Nathanson, et.al.)
Figure 3: Resonant Gate Transistor
1970‟s Bulk etched silicon wafers used as pressure sensors (Bulk MicromachingProcess)
TLN Technology Leads Nation
www.tln.co.in
1971 The microprocessor is invented
Figure 4:
(a) The Intel 4004 Microprocessor [Photo Courtesy of Intel Corporation]
(b) Busicom calculator [Photo Courtesy of Intel Corporation]
1979, Hewlett Packard developed the Thermal Inkjet Technology (TIJ). The TIJ rapidly heats ink, creating tiny bubbles. When the bubbles collapse, the ink squirts through an array of nozzles onto paper and other media. MEMS technology is used to manufacture the nozzles. The nozzles can be made very small and can be densely packed for high resolution printing. New applications using the TIJ have also been developed, such as direct deposition of organic chemicals and biological molecules such as DNA.
Figure 5: Nozzles in thermal Inkjet Printer 1982 "Silicon as a Structural Material," K. Petersen 1982 LIGA process, It allows for manufacturing of high aspect ratio microstructures. High aspect ratio structures are very skinny and tall. LIGA structures have precise dimensions and good surface roughness.
www.tln.co.in
TLN Technology Leads Nation
Figure 6: LIGA-micromachined gear for a mini electromagnetic motor[Courtesy of Sandia National Laboratories] 1982 Disposable blood pressure transducer (Honeywell) 1983 Integrated pressure sensor (Honeywell) 1983 "Infinitesimal Machinery" R. Feynman 1985 Sensonor Crash sensor (Airbag) 1985 The "Buckyball" is discovered 1986 The atomic force microscope is invented
Figure 7: Cantilever on an Atomic Force Microscope
1986 Silicon wafer bonding (M. Shimbo) 1988 Batch fabricated pressure sensors via wafer bonding (Nova Sensor) 1988 Rotary electrostatic side drive motors (Fan, Tai, Muller) 1991 Polysilicon hinge (Pister, Judy, Burgett, Fearing) 1991 The carbon nanotube is discovered 1992 Grating light modulator (Solgaard, Sandejas, Bloom) 1992 Bulk micromachining (SCREAM process, Cornell) 1993 Digital mirror display (Texas Instruments) 1993 MCNC creates MUMPS foundry service 1993 First surface micromachined accelerometer in high volume production (Analog Devices) 1994 Bosch process for Deep Reactive Ion Etching is patented
TLN Technology Leads Nation
www.tln.co.in
1996 Richard Smalley develops a technique for producing carbon nanotubes of uniform diameter 1999 Optical network switch (Lucent) 2000s Optical MEMS boom 2000s Bio-MEMS proliferate
3. Miniaturization Why miniaturization? Batch fabrication, lower cost per device, Less energy, less material consumed, Array of sensors possible, Can take advantage of different scaling laws, Integration with circuitry can reduce noise and improve sensitivity, Reliability may improve, Fewer defects per chip i.e. 106 defects/cm3->1 defect for every 106µm3
Size: 106 down Power: 106 up
The ENIAC Computer in 1946
A “Lap-top” Computer in 1996
Size: 108 down Power: 108 up
A “Palm-top” Computer in 2001
www.tln.co.in
TLN Technology Leads Nation
Figure 8: Miniaturization Micromachining has become a key technology for the miniaturization of sensors. Miniaturization is the trend to manufacture ever smaller mechanical, optical and electronic products and devices. In miniaturization the main problem is satisfying the scaling laws; otherwise the device may fail in functionality.
4. Scaling laws Why scaling is important in MEMS? Types of scaling laws Scaling in Geometry Scaling in Rigid-Body Dynamics Scaling in Electro Static Forces Scaling in Electro Magnetic Forces Scaling in Electricity Scaling in Fluid Mechanics Scaling in Heat Transfer
4.1. Scaling in Geometry: Scaling of physical size of objects. Scaling in phenomenological behavior is of both size and material characterization. Volume (V) and Surface (S) are two physical parameters that are frequently involved in machine design. Volume leads to the Mass & weight of device components. Volume relates to both mechanical and thermal inertia, the thermal inertia is a measure on how fast we can heat or cool a solid. Surface is related to pressure. If we let ℓ=linear dimension of a solid, we have: The Volume: V α ℓ3 The Surface: S α ℓ2 S/V= ℓ-1
4.2. Scaling in Rigid-Body Dynamics:
Forces are required to make parts to move such as in the case of micro actuators. Power is the source for generation of force.
TLN Technology Leads Nation
www.tln.co.in
In the case of miniaturization one need to understand the effect of reduction in the size on the power (P), force (F) or pressure (F) and the time (t) require to deliver the motion. Trimmer Force Scaling Vector F= [ ℓF] = [
]
Weight: W α ℓ3 Pressure: P α ℓ-2
4.3. Scaling in Electrostatic Forces:
When two parallel electric conductive plates is charged by a voltage it will creates electric potential field. The corresponding potential energy is, U=
=
V2
here: o , r α ℓ0 and W, L and d ℓ1 Therefore:
U α ℓ3 i.e. A 10 times reduction of linear size of electrodes will reduce 1000 time s in potential energy. 2
The Electrostatic forces: F α ℓ i.e. A 10 times reduction in electrode dimensions will reduce 100 times the magnitude of the electrostatic forces.
4.4. Scaling in Electro Magnetic Forces: The electromagnetic forces are the principal actuation forces in microscale or traditional motors and actuators. From Faradays law: Electromagnetic force F
α ℓ4
What the above scaling means is that reducing the wire length by half (1/2) would result in reduction of F by 24 = 16 times, whereas the reduction of electrostaic force with similar reduction of size would result in a factor of 22 = 4. This is the reason why electromagnetic forces are NOT commonly used in MEMS and microsystems as preferred actuation force.
TLN Technology Leads Nation
www.tln.co.in
4.5.
Scaling in Electricity: Electric Resistance: R=
α ℓ-1
in which ρ, L and A are respective electric resistivity of the material, the length and acrosssectional area of the conductor Resistive power loss: P=
α ℓ1
Where V is the applied voltage. Electric field energy: U=
E2 α ℓ-2
where is the permeativity of dielectric , and E is the electric field strength ∝ (ℓ) − 1
= = ℓ-2
Ratio of power loss to available power:
From “Nanosystems,” K. Eric Drexler, John Wiley & Sons, Inc., New York, 1992 Chapter 2, „Classical Magnitudes and Scaling Laws,‟ p. 34: Electric Quantity Current, i Voltage, V Resistance, R Capacitance, C Inductance, L Power, P
Index,a in ℓ 2 1 -1 1 1 2
a
4.6. Scaling in Fluid Mechanics: Two important quantities in fluid mechanics in flows in capillary conduits:
Figure 9: Capillary Conduits A. Volumetric Flow, Q: From Hagen-Poiseuille‟s equation:
Meaning a reduction of 10 in conduit radius→ 104 = 10000 times reduction in volumetric flow!
TLN Technology Leads Nation
www.tln.co.in
B. Pressure Drop, ΔP: From the same Hagen-Poiseuille‟s equation, we can derive:
Scaling: A reduction of 10 times in conduit radius → 103 = 1000 times increase in pressure drop per unit length!!
4.7. Scaling in Heat Transfer: Two concerns in heat flows in MEMS: A. How conductive the solid becomes when it is scaling down? This issue is related to thermal conductivity of solids. The thermal conductivity, k to be:
B. How fast heat can be conducted in solids: This issue is related to Fourier number defined as:
Scaling: A 10 times reduction in size → 102 = 100 time reduction in time to heat the solid.
5. Working principle of MEMS The best examples of MEMS are
5.1. Micro Sensors : Working principle of Micro Sensors is
Input Signa l
Micro Sensing Element
Transduction Element
Figure 10: Block Diagram of Basic MEMS Sensors
Output Signal
www.tln.co.in
TLN Technology Leads Nation
Example: 1. Acoustic Sensor: Acoustic wave sensor does not related to the sensing of acoustic waves transmitted in solids or other media, as the name implies. Primary application of these sensors is to act like “band filters” in mobile telephones and base stations.
Figure 11: Acoustic Sensor 2 sets of “Inter digital Transducers” (IDT) are created on a piezoelectric layer attached to a tiny substrate as shown. Energize by an AC source to the “Input IDT” will close and open the gaps of the finger electrodes, and thus surface deformation/stresses transmitting through the piezoelectric material The surface deformation/stresses will cause the change of finger electrodes in the “Output IDT” Any change of material properties (chemical attacks) or geometry due to torques will alter the I/O between the “Input IDT” and “Output IDT.” The sensing of contact environment or pressure can thus be accomplished. Example 2: BioMEMS: BioMEMS include the following three major areas: (1) Biosensors for identification and measurement of biological substances, (2) Bioinstruments and surgical tools, and (3) Bioanalytical systems for testing and diagnoses. A sensor for measuring the glucose concentration of a patient.
TLN Technology Leads Nation
www.tln.co.in
Figure 12: Bio MEMS to measuring the glucose concentration
The glucose in patient‟s blood sample reacts with the O2 in the polyvinyl alcohol solution and produces H2O2. The H2 in H2O2 migrates toward Pt film in a electrolysis process, and builds up layers at that electrode. The difference of potential between the two electrodes due to the build-up of H2 in the Pt electrode relates to the amount of glucose in the blood sample.
Example 3: Chemical Sensors: Work on simple principles of chemical reactions between the sample, e.g. ,O2 and the sensing materials, e.g., a metal. Types: 1. Chemiresistor 2.chemicapacitor 3. chemimechanical 4.Metal oxide gas Chemically Sensitive Polyimide Input Voltage or Current
Metal Insert Metal Electrodes
Change of Resistance Change of Capacitanc e
Measurand Gas
Figure 13: Basic Block Diagram of Chemical Sensor Example 4: Optical Sensors: These sensors are used to detect the intensity of lights. It works on the principle of energy conversion between the photons in the incident light beams and the electrons in the sensing materials. The following four (4) types of optical sensors are available: 1. photo voltaic junction
TLN Technology Leads Nation
www.tln.co.in
Figure 14: photo voltaic junction 2. photoconductive device
Figure 15: photo Conductive Device 3.photo diode
Figure 16: Photo Diode 4. Photo transistors
Figure 17: Photo Transistors Silicon (Si) and Gallium arsenide (GaAs) are common sensing materials. GaAs has higher electron mobility than Si- thus higher quantum efficiency. Other materials, e.g. Lithium (Li), Sodium (Na), Potassium (K) and Rubidium (Rb) are used for this purpose.
Example: 5. Pressure Sensors:
TLN Technology Leads Nation
www.tln.co.in
Micro pressure sensors are used to monitor and measure minute gas pressure in environments or engineering systems, e.g. automobile intake pressure to the engine. They are among the first MEMS devices ever developed and produced for “real world” applications. Micro pressure sensors work on the principle of mechanical bending of thin silicon diaphragm by the contact air or gas pressure.
Figure 18: Basic Pressure Sensor
The strains associated with the deformation of the diaphragm are measured by tiny “piezoresistors” placed in “strategic locations” on the diaphragm. These tiny piezoresistors are made from doped silicon. They work on the similar principle as “foil strain gages” with much smaller sizes (in μm), but have much higher sensitivities and resolutions. Major problems in pressure sensors are in the system packaging and protection of the diaphragm from the contacting pressurized media, which are often corrosive, erosive, and at high temperatures.
Example: 6. Thermal Sensors: Thermal sensors are used to monitor, or measure temperature in an environment or of an engineering systems. Common thermal sensors involve thermocouples and thermopiles. Thermal sensors work on the principle of the electromotive forces (emf) generated by heating the junction made by dissimilar materials (beads):
TLN Technology Leads Nation
www.tln.co.in
Figure 19: Thermal Sensor The generated voltage (V) by a temperature rise at the bead (ΔT) is: V= β ΔT where β = Seebeck coefficient:
5.2. Actuators: Output Action
Micro Actuating Element
Transduction Element
Power Supply
Figure 20: Basic Block Diagram of Actuator Example 1: Actuation Using Thermal Forces: Solids deform when they are subjected to a temperature change (ΔT) A solid rod with a length L will extend its length by ΔL = α ΔT, in which α = coefficient of thermal expansion (CTE) – a material property. When two materials with distinct CTE bond together and is subjected to a temperature change, the compound material will change its geometry as illustrated below with a compound beam:
Figure 21: Geometrical change because of heating
These compound beams are commonly used as microswitches and relays in MEMS products.
TLN Technology Leads Nation
www.tln.co.in
Example 2: Actuation Using Piezoelectric Crystals: A certain crystals, e.g., quartz exhibit an interesting behavior when subjected to a mechanical deformation or an electric voltage. This behavior may be illustrated as follows:
Figure 22: Actuation Using Piezoelectric Crystals
6. Examples of MEMS Devices 6.1.
Few examples of real MEMS products are: 1. Adaptive Optics for Ophthalmic Applications 2. Optical Cross Connects 3. Air Bag Accelerometers 4. Pressure Sensors 5. Mirror Arrays for Televisions and Displays 6. High Performance Steerable Micromirrors 7. RF MEMS Devices 8. Disposable Medical Devices 9. High Force, High Displacement Electrostatic Actuators 10. MEMS Devices for Secure Communications
6.2. MEMS devices used in Space exploration field include: 1.Accelerometers and gyroscopes for inertial navigation 2. Pressure sensors 3. RF switches and tunable filters for communication 4. Tunable mirror arrays for adaptive optics
www.tln.co.in
TLN Technology Leads Nation
5. Micro-power sources and turbines 6. Propulsion and attitude control 7. Bio-reactors and Bio-sensors, Microfluidics 8. Thermal control 9. Atomic clocks
7. Materials used in MEMS Fabrication
The materials used in MEMS and micro systems fabrications are Silicon: (Symbol: Si, Atomic number: 14, Atomic mass: 28.0855 u ± 0.0003 u, Electron configuration: [Ne] 3s23p2 , Melting point: 1,414 °C, Atomic radius: 117.6 pm, Discoverer: Jöns Jacob Berzelius) and Germanium: (Symbol: Ge, Atomic number: 32, Electron 10 2 2 configuration: [Ar] 3d 4s 4p , Discovered: 1886, Melting point: 938.2 °C, Atomic mass: 72.64 u ± 0.01 u, Discoverer: Clemens Winkler). Single crystal silicon is the most widely used substrate material for MEMS and microsystems. The popularity of silicon for such application is primarily for the following reasons: It is mechanically stable and it is feasible to be integrated into electronics on the same substrate. Electronics for signal transduction such as the p or n-type piezoresistive can be readily integrated with the Si substrate-ideal for transistors. Silicon is almost an ideal structure material. It has about the same Young‟s modulu‟s as steel (∼2x105 MPa[Minimum tensile strength]), but is as light as aluminum with a density of about 2.3 g/cm3 . As such, silicon will be the principal material to be studied. Other materials to be dealt with are silicon compounds such as: SiO2-Silicomdioxide or Silica, It acts as a diffusion mask permitting selective diffusions into silicon wafer through the window etched into oxide. SiO2 acts as the active gate electrode in MOS device structure. It is used to isolate one device from another. It provides electrical isolation of multilevel metallization used in VLSI. SiC-silicon carbide or Carborundum Si3N4 – Silicon Nitride polysilicon. Also will be covered are electrically conducting of silicon piezoresistors (N-Type, PType) and piezoelectric crystals for electromechanical actuations and signal transductions. An overview of polymers, which are the “rising stars” to be used as MEMS and microsystems substrate materials, will be studied too.
TLN Technology Leads Nation
www.tln.co.in
8. Microfabrication Processes 8.1. Photolithography:
Photolithography process involves the use of an optical image and a photosensitive film to produce desired patterns on a substrate. The “optical image” is originally in macro scale, but is photographically reduced to the micro-scale to be printed on the silicon substrates. The desired patterns are first printed on light-transparent mask, usually made of quartz. The mask is then placed above the top-face of a silicon substrate coated with thin film of photoresistive materials. The mask can be in contact with the photoresistave material, or placed with a gap, or inclined to the substrate surface:
Figure 23: Photolithography
8.2. Ion Implantation:
It is physical process used to dope silicon substrates. It involves “forcing” free charge-carrying ionized atoms of B, P of As into silicon crystals. These ions associated with sufficiently high kinetic energy will be penetrated into the silicon substrate. Physical process is illustrated as follows:
TLN Technology Leads Nation
www.tln.co.in
Figure 24: Ion Implantation
8.3. Diffusion:
Diffusion is another common technique for doping silicon substrates. Unlike ion implantation, diffusion takes place at high temperature. Diffusion is a chemical process. The profile of the spread of dopant in silicon by diffusion is different from that by ion implantation:
Figure 25: Diffusion
8.4. Oxidation:
SiO2 is an important element in MEMS and microsystems. Major application of SiO2 layers or films are: (1) To be used as thermal insulation media (2) To be used as dielectric layers for electrical insulation SiO2 can be produced over the surface of silicon substrates either by:
TLN Technology Leads Nation
www.tln.co.in
(1) Chemical vapor deposition (CVD), or (2) Growing SiO2 with dry O2 in the air, or wet steam by the following two chemical reactions at high temperature: Si (solid) + O2 (gas) → SiO2 (solid) Si (solid) + 2H2O (steam) → SiO2 (solid) + 2H2 (gas)
Figure 26: Oxidation
9. Fabrication Methods Basic integrated circuit fabrication involves 1. Deposition 2. Lithography
3. Removal
Wafer
Deposition
Lithography
Etch
Chips Figure 21: IC Fabrication Process Flow
Micromanufacturing: Applying Micromachining to create 3-D structures using 2-D processing 2D IC Process
3D structures Micromachining
Basic Types of Micromachining:
9.1.
Bulk Micromanufacturing:
TLN Technology Leads Nation
www.tln.co.in
Bulk micromanufacturing technique involves creating 3-D components by removing materials from thick substrates (silicon or other materials) using primarily etching method. Etching - dry or wet etching is the principal technique used in bulk micromanufacturing. Substrates that can be etched in bulk micromanufacturing include: 1. Silicon. 2. SiC 3. GaAs 4. Special polymers Less expensive in the process, but material loss is high. Suitable for microstructures with simple geometry. Limited to low-aspect ratio in geometry.
(a)
(b)
Figure 22 : Bulk Micromachining (a) Back-side Etching
(b) Front-side Etching
9.2. Surface Micromanufacturing:
Surface micromachining creates 3-D microstructures by adding material to the substrate. Requires the building of layers of materials over the substrate. Complex masking design and productions. Etching of sacrificial layers is necessary – not always easy and wasteful. The process is tedious and more expensive. There are serious engineering problems such as interfacial stresses and stiction. Major advantages: Not constrained by the thickness of silicon wafers. Wide choices of thin film materials to be used. Suitable for complex geometry such as micro valves and actuators.
Figure 23: Surface Micromachined Structure
9.3. LIGA Process:
LIGA: Lithographie, Galvanoformung, Abformung Form high aspect ratio structures on top of wafer
TLN Technology Leads Nation
www.tln.co.in
Uses molding and electroplating Synchrotron Radiation (X-Ray) used Most expensive in initial capital costs. Requires special synchrotron radiation facility for deep x-ray lithography. • Micro injection molding technology and facility for mass productions. • Major advantages are: Virtually unlimited aspect ratio of the microstructure geometry. Flexible in microstructure configurations and geometry. The only technique allows the production of metallic microstructures.
Figure 24: LIGA Process Feature:
Aspect ratio: 100:1 Gap: 0.25μm Size: a few millimeters
10. Design and Simulation using FEM Tools
There are many Finite Element Model Tools (FEM Tools), to design and simulate MEMS devices. Example: 1. Comsol Multiphysics 2. Intellisuite 3. MEMS Pro 4. HiQLAB 5. Coventor
11. Applications
www.tln.co.in
TLN Technology Leads Nation
11.1. Automotive domain: 1. Airbag Systems 2. Vehicle Security Systems 3. Intertial Brake Lights 4. Headlight Leveling 5. Rollover Detection 6. Automatic Door Locks 7. Active Suspension 11.2. Consumer Domain: 1. Appliances 2. Sports Training Devices 3. Computer Peripherals 4. Car and Personal Navigation Devices 5. Active Subwoofers 11.3. Industrial Domain: 1. Earthquake Detection and Gas Shutoff 2. Machine Health 3. Shock and Tilt Sensing 11.4. Military: 1. Tanks 2. Planes 3. Equipment for Soldiers
11.5. Biotechnology: 1. Polymerase Chain Reaction (PCR) microsystems for DNA amplification and identification 2. Micromachined Scanning Tunneling Microscopes (STMs) 3. Biochips for detection of hazardous chemical and biological agents 4. Microsystems for high-throughput drug screening and selection 5. Bio-MEMS in medical and health related technologies from Lab-On-Chip to biosensor & chemosensor.
11.6. The commercial applications include: 1. Inkjet printers, which use piezo-electrics or thermal bubble ejection to deposit ink on paper. 2. Accelerometers in modern cars for a large number of purposes including airbag deployment in collisions. 3. Accelerometers in consumer electronics devices such as game controllers, personal media players / cell phones and a number of Digital Cameras. 4. In PCs to park the hard disk head when free-fall is detected, to prevent damage and data
www.tln.co.in
TLN Technology Leads Nation
loss. 5. MEMS gyroscopes used in modern cars and other applications to detect yaw; e.g. to deploy a roll over bar or trigger dynamic stability control. 6. Silicon pressure sensors e.g. car tire pressure sensors, and disposable blood pressure sensors. 7. Displays e.g. the DMD chip in a projector based on DLP technology has on its surface several hundred thousand micromirrors. 8. Optical switching technology, which is, used for switching technology and alignment for data communications. 9. Interferometric modulator display (IMOD) applications in consumer electronics (primarily displays for mobile devices). 10. Improved performance from inductors and capacitors due the advent of the RF-MEMS technology.
www.tln.co.in
TLN Technology Leads Nation
References: 1. Lectures of Dr. Tai-Ran Hsu Professor, Department of Mechanical Engineering San José State University One Washington Square San José, California 95192-0087 Office: Engineering 117B Telephone: (408) 924-3905 Fax: (408) 924-3995 E-mail:
[email protected] 2. Lecture of Prof. Santiram Kal, Department of Electronics & Electrical Communication Engineering Indian Institute of Technology, Kharagpur.
