nano-ram
TRANSCRIPT
NANO-RAM
ABSTRACT
Nano-RAM is a proprietary computer memory technology from the company Nantero
and NANOMOTOR is invented by University of bologna and California nano systems. NRAM
is a type of nonvolatile random access memory based on the mechanical position of carbon
nanotubes deposited on a chip-like substrate. In theory the small size of the nanotubes allows for
very high density memories.
Nantero also refers to it as NRAM in short, but this acronym is also commonly used as a
synonym for the more common NVRAM, which refers to all nonvolatile RAM
memories.Nanomotor is a molecular motor which works continuously without the consumption
of fuels. It is powered by sunlight. The researches are federally funded by national science
foundation and national academy of science.
Carbon Nanotubes Carbon nanotubes (CNTs) are a recently discovered allotrope of
carbon.They take the form of cylindrical carbon molecules and have novel properties that make
them potentially useful in a wide variety of applications in nanotechnology, electronics, optics,
and other fields of materials science.
They exhibit extraordinary strength and unique electrical properties, and are efficient
conductors of heat. Inorganic nanotubes have also been synthesized. A nanotube is a member of
the fullerene structural family, which also includes buckyballs. Whereas buckyballs are spherical
in shape, a nanotube is cylindrical, with at least one end typically capped with a hemisphere of
the buckyball structure.
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CHAPTER 1::INTRODUCTION
NANOTECHNOLOGY
There's an unprecedented multidisciplinary convergence of scientists dedicated to
the study of a world so small, we can't see it -- even with a light microscope. That world is
the field of nanotechnology, the realm of atoms and nanostructures. Nanotechnology is so
new, no one is really sure what will come of it. Even so, predictions range from the ability
to reproduce things like diamonds and food to the world being devoured by self-replicating
nanorobots.
In order to understand the unusual world of nanotechnology, we need to get an idea
of the units of measure involved. A centimeter is one-hundredth of a meter, a millimeter is
one-thousandth of a meter, and a micrometer is one-millionth of a meter, but all of these
are still huge compared to the nanoscale. A nanometer (nm) is one-billionth of a meter,
smaller than the wavelength of visible light and a hundred-thousandth the width of a
human hair.
As small as a nanometer is, it's still large compared to the atomic scale. An atom
has a diameter of about 0.1 nm. An atom's nucleus is much smaller -- about 0.00001 nm.
Atoms are the building blocks for all matter in our universe. You and everything around
you are made of atoms. Nature has perfected the science of manufacturing matter
molecularly. For instance, our bodies are assembled in a specific manner from millions of
living cells. Cells are nature's nanomachines. At the atomic scale, elements are at their
most basic level. On the nanoscale, we can potentially put these atoms together to make
almost anything.
In a lecture called "Small Wonders: The World of Nanoscience," Nobel Prize
winner Dr. Horst Störmer said that the nanoscale is more interesting than the atomic scale
because the nanoscale is the first point where we can assemble something -- it's not until
we start putting atoms together that we can make anything useful.
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Experts sometimes disagree about what constitutes the nanoscale, but in general, you can
think of nanotechnology dealing with anything measuring between 1 and 100 nm. Larger than
that is the microscale, and smaller than that is the atomic scale.
Nanotechnology is rapidly becoming an interdisciplinary field. Biologists, chemists,
physicists and engineers are all involved in the study of substances at the nanoscale. Dr.
Störmer hopes that the different disciplines develop a common language and communicate with
one another [source: Störmer]. Only then, he says, can we effectively teach nanoscience since
you can't understand the world of nanotechnology without a solid background in multiple
sciences.
One of the exciting and challenging aspects of the nanoscale is the role that quantum
mechanics plays in it. The rules of quantum mechanics are very different from classical physics,
which means that the behavior of substances at the nanoscale can sometimes contradict common
sense by behaving erratically. You can't walk up to a wall and immediately teleport to the other
side of it, but at the nanoscale an electron can -- it's called electron tunneling. Substances that
are insulators, meaning they can't carry an electric charge, in bulk form might
become semiconductors when reduced to the nanoscale. Melting points can change due to an
increase in surface area. Much of nanoscience requires that you forget what you know and start
learning all over again.
At the nanoscale, objects are so small that we can't see them -- even with a light
microscope. Nonscientists have to use tools like scanning tunneling microscopes or atomic force
microscopes to observe anything at the nanoscale. Scanning tunneling microscopes use a weak
electric current to probe the scanned material. Atomic force microscopes scan surfaces with an
incredibly fine tip. Both microscopes send data to computer, which can assemble the information
and project it graphically onto a monitor.
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NANO-RAM
Basically in NANO-RAM, there are two words of different technologies and are
attached together. First one is the Nanotechnology and second one is the Ramdom access
memory. We have already taken information about the nanotechnology, lets see what is RAM.
What these both contribute to the new research called NANO-RAM.
Random-access memory (RAM) is a form of computer data storage. Today, it takes the
form of integrated circuits that allow stored data to be accessed in any order (i.e., at random).
"Random" refers to the idea that any piece of data can be returned in a constant time, regardless
of its physical location and whether or not it is related to the previous piece of data.
By contrast, storage devices such as magnetic discs and optical discs rely on the physical
movement of the recording medium or a reading head. In these devices, the movement takes
longer than data transfer, and the retrieval time varies based on the physical location of the next
item.
Most forms of modern random access memory (RAM) are volatile storage,
including dynamic random access memory (DRAM) and static random access
memory (SRAM). Content addressable memory and dual-ported RAM are usually implemented
using volatile storage. Early volatile storage technologies include delay line
memory and William’s tube.
Volatile memory, also known as volatile storage, is computer memory that requires
power to maintain the stored information, unlike non-volatile memory which does not require a
maintained power supply. It has been less popularly known as temporary memory.
Nano-Ram is the new era memory which is not now yet completely discovered but it
shows a light towards the new age of electronics which totally has a new look and working
strategies. It now travels from micrometer to nanometer with a great working capabilities and
strengths.
Nano-RAM is a proprietary computer memory technology from the company Nantero
and NANOMOTOR is invented by University of bologna and California nano systems. RAM is
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a type of nonvolatile random access memory based on the mechanical position of carbon
nanotubes deposited on a chip-like substrate. In theory the small size of the nanotubes allows for
very high density memories. Nantero also refers to it as NRAM in short, but this acronym is also
commonly used as a synonym for the more common NVRAM, which refers to all nonvolatile
RAM memories. Nanomotor is a molecular motor which works continuously without the
consumption of fuels. It is powered by sunlight. The research is federally funded by national
science foundation and national academy of science.
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CARBON NANOTUBES
The term nanotubes is normally used to refer to the carbon nanotubes, which has received
enormous attention from researchers over the last few years and promises, along with close
relatives such as the nanohorn, a host of interesting applications. There are many others types of
nanotubes, from various inorganic kinds such as, those made from boron nitride, to organic ones,
such as those made from self-assembling cyclic peptides (proteins components) or from naturally
occurring heat shock proteins(extracted from bacteria that thrive in extreme environments).
However, carbon nanotubes excites the most interest, promise the greatest variety of application
and currently appear to have by far the highest commercial potential.
Carbon nanotubes were discovered in 1991 by Sumio Iijima of NEC and are effectively
long, thin cylinders of graphite, which you wiil be familiar with as the material in a pencil or as
the basis of some lubricants. Graphite is made up of layers of carbon atoms arranged in a
hexagonal lattice, like chicken wire. Though the chicken wire structure itself is very strong, the
layers themselves sure not chemically bonded to each other but held together by weak forces
called Van der Waals. It is the sliding across each other of these layers that gives graphite its
lubricating qualities and makes the mark on a piece of paper as you draw your pencil over it.
Now imagine taking one of these sheets of chicken wire and rolling it up into a cylinder
and joining the loose wore ends. The result is a tube that was once described by Richard Smalley
(who shared the Nobel Prize for the discovery of a related form of carbon called
buckminsterfullerene) as
“In one direction….the strongest damn thing you’ll ever make in this universe”. In
addition to their remarkable strength, this is usually quoted a 100 times that of steel at one-sixth
of the weight (this is tensile strength-the ability to withstand a stretching force without breaking),
carbon nanotubes have shown a surprising array of other properties. They can conduct heat as
efficiently as diamond, conduct electricity as efficiently as copper, yet also be semiconducting
(like the materials that make up the chips in our computers). They can produce streams of
electrons very efficiently (field emission), which can be used to create light in displays for
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televisions or computers, or even in domestic lighting, and they can enhance the fluorescence of
materials they are close to. Their electrical properties can be made to change in the presence can
act like miniature springs and they can even be stuffed with other material. Nanotubes and their
variants hold promise for storing fuels such as hydrogen or methanol for use in fuel cells and
they make good support for catalysts.
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CHAPTER 2::CARBON NANOTUBES
STRUCTURE OF CARBON
NANOTUBES
Carbon nanotubes (CNTs; also known as buckytubes) are allotropes of carbon with a
cylindrical nanostructure. Nanotubes have been constructed with length-to-diameter ratio of up
to 132,000,000:1] which is significantly larger than any other material. These
cylindrical carbon molecules have novel properties that make them potentially useful in many
applications in nanotechnology, electronics, optics and other fields of materials science, as well
as potential uses in architectural fields. They exhibit extraordinary strength and
unique electrical properties, and are efficient thermal conductors.
The nature of the bonding of a nanotube is described by applied quantum chemistry,
specifically, orbital hybridization. The chemical bonding of nanotubes is composed entirely
of sp2 bonds, similar to those of graphite. This bonding structure, which is stronger than
the sp3 bonds found in diamonds, provides the molecules with their unique strength. Nanotubes
naturally align themselves into "ropes" held together by Van der Waals forces.
Since carbon nanotubes were discovered on accident by Sumio Iijima in 1991 during
another experiment, hundreds of studies have been started and dedicated to achieving a better
understanding of the structure of carbon nanotubes. Although the structure of carbon nanotubes
has been extensively studied by researchers and scientists in a wide variety of fields including
materials science, architecture, agriculture and engineering, the full implications of this tiny
microscopic wonder are still locked away in its unique natural creation, varied structural
components and its ability to be both immensely flexible as well as incredibly strong.
Carbon comes in many forms. Two well-known forms of carbon are graphite and
diamond. Graphite and diamond have drastically different mechanical properties such as
hardness. Diamond is one of the hardest materials known to man. It can cut through glass.
Graphite, on the other hand, is a very soft material, used in pencil lead.
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The difference in properties is due to the structure of the atoms and their bonds in the
material, also known as the materials crystal structure. Graphite is made up of stacked sheets of
hexagons with a carbon atom at each corner of the hexagon, and looks much like chicken wire.
These sheets are stacked one on top of the other, but easily slip and slide. Diamond has a
tetragonal crystal structure with very few slip planes.
Carbon nanotubes are a fairly new form of carbon.
A carbon nanotube structure looks
like sheets of graphite that have been rolled up to form
small tubes. This small
difference in structure leads to a much stronger, stiffer
material. Carbon nanotubes have a diameter of 1 to 10
nanometers, yet they are 50 times stronger than steel.
The special nature of carbon combines with the molecular perfection of buckytubes
(single-wall carbon nanotubes) to endow them with exceptionally high material properties
such as electrical and thermal conductivity, strength, stiffness, and toughness. No other
element in the periodic table bonds to itself in an extended network with the strength of the
carbon-carbon bond. The delocalised pi-electron donated by each atom is free to move about
the entire structure, rather than stay home with its donor atom, giving rise to the first molecule
with metallic-type electrical conductivity. The high-frequency carbon-carbon bond vibrations
provide an intrinsic thermal conductivity higher than even diamond.
In most materials, however, the actual observed material properties - strength,
electrical conductivity, etc. - are degraded very substantially by the occurrence of defects in
their structure. For example, high strength steel typically fails at about 1% of its theoretical
breaking strength. Buckytubes, however, achieve values very close to their theoretical limits
because of their perfection of structure - their molecular perfection. This aspect is part of the
unique story of buckytubes.
Buckytubes are an example of true nanotechnology: only a nanometer in diameter, but molecules
that can be manipulated chemically and physically. They open incredible applications in materials,
electronics, chemical processing and energy management.
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Basic Structure
Buck tubes are single-wall carbon nanotubes,
in which a single layer of graphite - graphene - is
rolled up into a seamless tube. Graphene consists of
a hexagonal structure like chicken wire. If you
imagine rolling up graphene or chicken wire into a
seamless tube, this can be accomplished in various
ways. For example, carbon-carbon bonds (the wires
in chicken wire) can be parallel or perpendicular to
the tube axis, resulting in a tube where the hexagons
circle the tube like a belt, but are oriented differently. Alternatively, the carbon-carbon
bonds need not be either parallel or perpendicular, in which case the hexagons will spiral
around the tube with a pitch depending on how the tube is wrapped. Above figure illustrates
these point.
Carbon nanotubes appear to be sheets of graphite cells that have been mended together
to look almost like a latticework fence and then rolled up in a tube shape. Although this is a
simple explanation for the look of the structure of carbon nanotubes, this is not how carbon
nanotubes are created, nor does it explain their immense strength or other incredible structural
abilities.
CLASSIFICATION OF CARBON NANOTUBES
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One of the major
classifications of carbon
nanotubes is into singled-
walled varieties (SWNT’s)
which have a single cylinder wall
and multi-walled varieties
(MWNT’s) which have
cylinders within cylinders.
The length of both type vary greatly, depending upon on the way they are made and are
generally nanoscopic rather than microscopic i.e. greater than 100 micrometers. The aspect ratio
(length divided by diameter) is typically greater than100 and can be up to 10,000, but recently
even this was made to look small. IN May 2002, SWNT strand were made in which the SWNT’s
were claimed to be as long as 20 cm. Even more recently, the same group has made strand of
SWNT’s 160cm long, but the precise make up of these strand has not yet been made clear. A
group in china has found, purely by accident that packs of relatively short carbon nanotubes can
be drawn out into a bundle of fibers, making a thread only 0.2 mm in diameter but up to 30 cm
long. The joins between the nanotubes in this thread represent a weakness but heating the thread
has been found to increase the strength significantly, presumably through some sort of fusing of
the individual tubes.
SINGLE-WALLED CARBON NANOTUBES (SWNT’S)
Single-wall nanotubes (SWNT) are tubes of graphite that are normally capped at the
ends. They have a single cylindrical wall. The structure of a SWNT can be visualized as a layer
of graphite, a single atom thick, called graphene, which is rolled into a seamless cylinder.Most
SWNT typically have a diameter of close to 1 nm. The tube length, however, can be many
thousands of times longer.
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SWNT are more pliable yet harder to make
than MWNT. They can be twisted, flattened, and bent
into small circles or around sharp bends without
breaking. SWNT have unique electronic and mechanical
properties which can be used in numerous applications,
such as field-emission displays, nanocomposite
materials, nanosensors, and logic elements. These
materials are on the leading-edge of electronic
fabrication, and are expected to play a major role in the next generation of miniaturized
electronics.
The ability of single-walled carbon nanotubes to bend at the extreme angle observed
in figure 1opened the possibility that the proposed structure of SWNTs was not accurate since
it is suspicious that a cylinder composed of a closed graphitic sheet could bend that far without
visible damage to the tube.
SWNT’s can be conducting like metal or semiconducting and taking into account their
small diameter and their huge aspect ratio, SWNT’s are close to an ideal one dimensional
system. The general composition of SWNT’s
MULTI-WALLED CARBON NANOTUBES (MWNT’s)
Multi-walled carbon nanotubes are basically concentric cylindrical graphite tubes. In these more
complex structures, the different SWNT’s that form the MWNT may have quite different
structures by length and chirality). MWNT’s are typically 100 times longer than they are wide
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COMPOSITION OF SWNTs
Average outside diameter: 1.1 nm
Length: 5-30 mm
Components Contents (%)
C 96.30
Al 0.08
Cl 0.41
Co 2.91
S 0.29
Analysis Method: Energy Dispersive X-ray Spectroscopy
NANO-RAM
and have outer diameter mostly in the tens of nanometer. Although
it is easier to produce significant quantities of MWNT’s than
SWNTs, their structures are less well understood than SWNT
because of their greater complexity and variety. Multitudes of
exotic shapes and arrangement, often with imaginative names such
as bamboo-trunks, sea urchins etc.
Many of the nanotube application now being considered or
put into practice involve multi-walled nanotubes, because they are
easier to produce in large quantities at a reasonable price and have
been available in decent amount for much longer than SWNTs.
They involve typically 8 to 15 walls and around 19 nanometers
wide and 10 micrometer long. Many companies are moving into this space, notably formidable
players like Mitsui, with plans to produce similar types of MWNT in hundred of tons a year, a
quantity that is greater but not hugely so that the current production of Hyperion Catalysis. This
is an indication that even these less impressive and exotic nanotubes hold promise of
representing a sizable market in the near future. The composition of MWNT’s is as shown in
table:
COMPOSITION OF MWNTs
Outside diameter: ≤8 nm
Inside diameter: 2-5 nm
Length: 10-30 µm
Components Contents (%)
C 97.44
Al 0.19
Cl 1.03
Co 1.10
S 0.24
Analysis Method: Energy Dispersive X-ray Spectroscopy
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BENEFITS OF CARBON NANOTUBES
The underlying excitement over CNTs comes from their wide range of behaviors and
properties. By learning about the properties of CNTs, it is possible to imagine enormous
possibilities for their application.
Strength and Elasticity :
CNTs can be really strong. Their tensile strength, a measure of the amount of force
which a specimen can withstand before tearing, is approximately 100 times greater than that of
steel. Strength of CNTs results from the covalent sp² bonds formed between the individual
carbon atoms. This bond is stronger than the sp3 bond in diamonds. CNTs are held together by
Van der Waals forces, forming a rope-like structure [10]. Another reason why they are so strong
is because they are just one large molecule. Unlike other materials, carbon nanotubes do not
have weak-spot, such as steel. CNTs also have a high elastic modulus, a measure of the
material’s tendency to deform elastically when a force is applied to it.
Electrical and Magnetic:
Metallic-like CNTs are better conductors than metals. The only other materials that can
conduct better than CNTs are superconductors, which theoretically have zero electrical
resistance. It has also been observed that, under the influence of a large magnetic field, the band
gap of semi-conducting CNTs can be slightly lowered.
Optical:
A defect-free carbon nanotube is like an optical fiber. Fibers with large cores are called
multi-mode fibers because several wavelengths (or eigenmodes) are allowed to propagate,
usually at different speeds, along the fiber. For data transmission, so-called single-mode fibers
are preferred because they allow for higher data rates. A single-wall nanotube is almost a single-
mode fiber for electrons. Theory predicts the existence of two propagating eigenmodes for a
single-wall nanotube, independent of its diameter.
Chemical:
The chemical reactivity of a CNT is, compared with a graphene sheet, enhanced as a
direct result of the curvature of the CNT surface. Carbon nanotube reactivity is directly related to
the pi-orbital mismatch caused by an increased curvature. Therefore, a distinction must be made
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between the sidewall and the end caps of a nanotube. For the same reason, a smaller nanotube
diameter results in increased reactivity. Covalent chemical modification of either sidewalls or
end caps has been shown to be possible
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CHAPTER 3:: NANO-RAM
STRUCTURE OF NANO-RAM
Nano-RAM is a proprietary computer memory technology from the company Nantero
and NANOMOTOR is invented by University of bologna and California nano systems. RAM is
a type of nonvolatile random access memory based on the mechanical position of carbon
nanotubes deposited on a chip-like substrate. In theory the small size of the nanotubes allows for
very high density memories. Nantero also refers to it as NRAM in short, but this acronym is also
commonly used as a synonym for the more common NVRAM, which refers to all nonvolatile
RAM memories. Nanomotor is a molecular motor which works continuously without the
consumption of fuels. It is powered by sunlight. The researches are federally funded by national
science foundation and national academy of science.
The design is quite simple. Nanotubes can serve
as individually addressable electromechanical
switches arrayed across the surface of a microchip,
storing hundreds of gigabits of information
may be even a terabit. An electric field applied to
nanotubes would cause it to flex downward
into depression etched onto the chip’s surface, where it
would contact rather another nanotube or touch a
metallic electrode. Once bent, the nanotubes can remain
that way, including when the
power is turned off, allowing for non-volatile operation. Vanderwaals forces, which are weak
molecular forces of attractions, would hold the switch in place until application of fields of
different polarity causes the nanotube to return to its straightened position.
This nano electromechanical memory, called NRAM, is a memory with actual moving
parts, with dimensions measured in nanometers. Its carbon nanotube based technology makes
advantage of vaanderwaals force to create basic on off junctions of a bit. Vaanderwaals forces
interaction between atoms that enable noncovalant binding. They rely on electron attractions that
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arise only at nano scale levels as a force to be reckoned with. The company is using this property
in its design to integrate nanoscale material property with established cmos fabrication
technique.
Nantero's technology is based on a
well-known effect in carbon nanotubes where
crossed nanotubes on a flat surface can either
be touching or slightly separated in the vertical
direction (normal to the substrate) due to Van
der Waal's interactions. In Nantero's
technology, each NRAM "cell" consists of a
number of nanotubes suspended on insulating
"lands" over a metal electrode. At rest the nanotubes lie above the electrode "in the air", about
13 nm above it in the current versions, stretched between the two lands. A small dot of gold is
deposited on top of the nanotubes on one of the lands, providing an electrical connection, or
terminal. A second electrode lies below the surface, about 100 nm away.
NRAMs are built by depositing masses of nanotubes on a pre-fabricated chip containing
rows of bar-shaped electrodes with the slightly taller insulating layers between them. Tubes in
the "wrong" location are then removed, and the gold terminals deposited on top. Any number
of methods can be used to select a single cell for writing, for instance the second set of
electrodes can be run in the opposite direction, forming a grid, or they can be selected by
adding voltage to the terminals as well, meaning that only those selected cells have a total
voltage high enough to cause the flip.
Currently the method of removing the unwanted nanotubes makes the system
impractical. The accuracy and size of the epitaxial machinery is considerably "larger" that the
cell size otherwise possible. Existing experimental cells have very low densities compared to
existing systems, some new method of construction will have to be introduced in order to make
the system practical.
As we see the structure and the construction of the Nano-Ram, now let study how the
data is being stored in ths Nano-Ram.
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STORAGE IN NANO-RAM
Nantero has created multiple prototype devices, including an array of ten billion
suspended nano tube junctions on a single silicon wafer. NRAM technology will achieve very
high memory densities: at least 10-100 times our current best. Nantero's design for NRAM™
involves the use of suspended nanotube junctions as memory bits, with the "up" position
representing bit zero (Off) and the "down" position representing bit one (On).
Bits are switched between states through the application of electrical fields. The wafer (A
small adhesive disk of paste) was produced using only standard semiconductor processes,
maximizing compatibility with existing semiconductor factories.
NRAM works by balancing the on ridges of silicon. Under differing electric charges, the
tubes can be physically swung into one or two positions representing
one and zeros. Because the tubes are very small-under a thousands of
time-this movement is very fast and needs very little power, and
because the tubes are a thousand times conductive as copper it is very
to sense to read back the data. Once in position the tubes stay there
until a signal resets them.
The bit itself is not stored in the nano tubes, but rather is
stored as the position of the nanotube. Up is bit 0 and down is bit
1.Bits are switched between the states by the application of the
electric field.
The technology work by changing the charge placed on a latticework of crossed nanotube.
By altering the charges, engineers can cause the tubes to bind together or separate, creating ones
and zeros that form the basis of computer memory. If we have two nano tubes perpendicular to
each other one is positive and other negative, they will bend together and touch. If we have two
similar charges they will repel. These two positions are used to store one and zero. The chip will
stay in the same state until you make another change in the electric field. So when you turn the
computer off, it doesn't erase the memory .We can keep all the data in the NRAM and gives your
computer an instant boot.
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What causes this to act as a memory is that the two positions of the nanotubes are both
stable. In the off position the mechanical strain on the tubes is low, so they will naturally remain
in this position and continue to read "0". When the tubes are pulled
into contact with the upper electrode a new force, the tiny Van der
Waals force, comes into play and attracts the tubes enough to
overcome the mechanical strain. Once in this position the tubes will
again happily remain there and continue to read "1". These positions
are fairly resistant to outside interference like radiation that can
erase or flip memory in a conventional DRAM.
NRAMs are built by depositing masses of nanotubes on a
pre-fabricated chip containing rows of bar-shaped electrodes with
the slightly taller insulating layers between them. Tubes in the
"wrong" location are then removed, and the gold terminals deposited
on top. Any number of methods can be used to select a single cell
for writing, for instance the second set of electrodes
can be run in the opposite direction, forming a grid, or they can be selected by adding voltage to
the terminals as well, meaning that only those selected cells have a total voltage high enough to
cause the flip.
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ADVANTAGES OF NANO-RAM
Permanently nonvolatile
High speed similar to DRAM/SRAM
High density similar to DRAM
Unlimited lifetime
Low power consumption
Data storage
CMOS-compatible manufacturing process
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APPLICATIONS AND LIMITATIONS
APPLICATIONS:
Computer and Laptops
(Enabling instant –on performance, with no for boot up)
Mobile devices
(Faster storage of more data for PDA’s and handhelds)
Embedded memory
(More powerful microprocessor, microcontroller, other logic device)
High speed network serve
Faster and Denser
LIMITATIONS:
Over supply of DRAM
Is relatively costly
NRAM is still in research phase
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CONCLUSION
This paper gives an over-view of application of nanotechnology in field of electronics. Moore’s
law has held true for almost 40 years now, but the current lithographic technology has physical
limits when it comes to making things smaller and the semiconductor industry which often refers
to the collection of these as the “red brick wall” thinks that the wall will be hit in around fifteen
years. At the point a new technology will have to take over and nanotechnology offers a variety
of potentially viable options and carbon nanotube are one of the most commonly mentioned
building blocks of nanotechnology.We could say that the prospects of nanotechnology are very
bright.Nanotechnology will be an undeniable force in near future. Beginning &usage of NRAM
will give rise to instant ON computers. Nonvolatile memories will enable instant booting of
computers. Large memories can be building with nanotube technology. Nonvolatile memories
offer much better performance combined with data storage when the power is turned OFF.
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REFERENCES
Carbon Nanotube–Based Nonvolatile Random Access Memory for Molecular
Computing: Thomas Rueckes, Kyoungha Kim, Ernesto Joselevich, Greg Y. Tseng,
Chin-Li Cheung, Charles M. Lieber
Nano Engineered Memory solutions-IEEE journal.
www.nantero.com/tech.html
10 Emerging technologies – MIT technology review
www.worldlingo.com/ma/enwiki/en/Nano-RAM
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