CARBON NANOTUBES IN ELECTRONICS

1. TABLE OF CONTENT
1) Introduction……………………………………………………………………1
1.1 Schematic of Carbon Nanotube Made From Rolled Grapheme Sheet
1.2 Single Vs Multi-Walled CNT’s
2) Problem Statement…………………………………………………………….2
3) Classification of CNT’s……………………………………………………….3
3.1 Single-Walled Nanotube (SWNT)
3.2 Multi-Walled Nanotube (MWNT)
4) Synthesis CNT’s in Electronic Applications………………………………….5
5) Advantages & Disadvantages…………………………………………………6
6) Applications of CNT’s………………………………………………………...6
6.1 Sensors & Probes
6.2 Electrochemical Devices
6.3 Hydrogen Storage
7) Results & Discussion………………………………………………………….7
8) Conclusion…………………………………………………………………….8
9) Reference……………………………………………………………………...9

2. INTRODUCTION
Carbon nanotubes are first observed by
Endo. This observed have lead to a great
dal of scientific attention to unique
material. Iijima’s detailed observations
are make followed, caused theoretical
models to start appear, predict unusual
electronic properties for the class of
material. At that time, carbon nanotube
was predicted to be either metals or
semiconductors based on their carbon
atom’s arrangement.
Carbon nanotubes (CNTs) is a
tube-shaped material which made by
carbon. It’s having a diameter measuring
on the nanometer scale for which
nanometer is one-billionth of a meter, or
about 10,000 times smaller than a human
hair. CNTs are unique with the strong
bonding between atoms and ultimate
aspect ratios in the tubes. CNTs can be
as thin as a few manometer and be as
long as hundreds of micron.
CNTs have many structure,
differing in length, thickness and number
of layers. The characteristics of CNTs
are depending on the graphene sheet.
The way of graphene sheet rolled up to
form the tube influence it to act metallic
or as a semiconductor
Schematic of carbon nanotube made
from rolled grapheme sheet
There are two category of CNTs
which are single-walled (SWNT) or
multi-walled nanotubes (MWNT). A
single-walled carbon nanotube is shaped
like a regular straw, only has 1 layer or
wall. Multi-walled carbon nanotubes are
a collection of nested tube with
increasing diameters.
Single vs multi-walled CNT
Carbon Nanotubes (CNTs)
exhibit uncommon electrical properties
for organic materials. CNTs have a huge
potential in electric and electronic
application such as photovoltaic,
sensors, semiconductor devices,
displays, conductors, smart textiles and
energy conversion devices. The type of
CNT that is pf interest in the electronics
industry is single-walled tube. The
material is made from a carbon lattice
that is one carbon atom thick.
Carbon and silicon are both small
size. The number of transistors made
from CNTs that can be placed on a chip
is much greater than the number that can
be placed on a silicon chip. CNT chip
are more faster, efficient and they
generate much less heat than silicon
chips. In other words, CNT chips would
give high speed and longer battery life
without overheating and need for fans to
dissipate excess heat.

3. PROBLEM STATEMENT
Since its discovery, carbon
nanotubes or in other name is CNTs, has
been very famous among electronics part
industry. What is CNTs? What it do?
CNTs is a tube-shaped materials that
made up of carbon which its diameter is
measuring by manometer scale. Through
this, we can only imagine how small this
CNTs and furthermore, it also bring lots
of pros in this industry. CNTs have lots
of usage in electronics industry such as
flexible electronics, ultra-high sensitive
sensors, high frequency electronics,
opto-electronics and many more. CNTs
have unique characteristics which is it
have two states; metallic state and
semiconducting state. It also can conduct
high electricity. CNTs also have high
tensile strength and also very flexible.
Moreover, it can stretch up to 18% of
elongation to failure. Plus, carbon
nanotubes contain low thermal
expansion coefficient and high thermal
conductivity.
It’s been said that CNTs’ unique
characteristics making it the most
favourable material when producing
electronic parts such as transistor. But, a
great invention also come with a
problem. In this case, it comes up with
two major problems which are the
mixture problem and the electrical
resistance problem.
The first problem that come up is
the mixture problem. As we know,
carbon nanotubes are available in two
state; metallic and semiconductor.
Furthermore, integrated circuit using up
to 100% of semiconductor. But the
problem is, how to separate metallic
CNTs from semiconductor? This
problem is still on research by the
scientist around the world.
The second problem is the
electrical problem. In electronic parts,
the nanotubes will be connected with
other metallic components. When the
electricity flows through them, the
electrical resistance will increase while
the size of the connection is decreasing.
The higher usage of CNTs will be results
in increasing of resistance. This is
because CNTs’ diameter is on scale of
10 nm or less.by increasing the size of
the connection means less CNTs
available in the electrical parts, thus
making the advantage of the CNTs
disappear.

4. CLASSIFICATION OF CNTs
Carbon nanotubes which also
called CNTs is make from graphite. The
molecular structure of graphite
resembles stacked. When grapheme are
rolled into a cylinder with their edges
joined, CNTs are formed. CNTs can
have a variety of diameter, length, and
functional group content. CNTs are
divided into two type. A nanotube that
consist of one tube of graphite, a one-
atom thick is called single-walled
nanotube while consist of a number of
concentric tubes called multi-walled
nanotubes.
Single-walled Nanotube (SWNT)
Most single-walled nanotubes
(SWNTs) have a diameter of close to
1 nanometer, and can be extremely
longer. The structure of a SWNT are
form by wrapping a one-atom-thick
layer of graphite called graphene into a
seamless cylinder. The way the graphene
sheet is wrapped is represented by a pair
of indices (n.m). The
integers n and m denote the number of
unit vectors along two directions in the
honeycomb crystal lattice of graphene.
If m = 0, the nanotubes are
called zigzag nanotubes, and if n = m,
the nanotubes are
called armchair nanotubes. Otherwise,
they are called chiral. The diameter of an
ideal nanotube can be calculated from its
(n,m) indices as follows
d =
𝑎
𝜋
√(𝑛2 + 𝑛𝑚 + 𝑛2 =
78.3√(( 𝑛 + 𝑚)2 − 𝑛𝑚) 𝑝𝑚,
where a = 0.246 nm.
Carbon nanotubes are predicted to
be metallic or semiconducting due to
diameter and the helicity of the
arrangement of graphitic rings in walls.
This prediction can be probe by
Scanning
Tunnelling Microscopy (STM).
STM can resolve both atomic structure
and the electronic density of states.
Single-walled carbon nanotubes
(SWNTs) have many exceptional
electronic properties. SWNTs is an
effective thin-film semiconductor that
suitable for integration into transistors
and others classes of electronic devices.
The large number of SWNTs enable
excellent device-level performance
characteristics even with SWNTs are
electronically heterogeneous.
Measurements on p- and n-channel
transistors involve as many as
2100 SWNTs reveal device-level
mobility and scaled transconductance
that approaching 1000 cm2 V−1 s−1 and
3000 S m−1, respectively, and with
current outputs of up to 1 A in devices
that use interdigitated electrodes. P-type
metal-oxide-semiconductor logic, PMOS
and Complementary Metal Oxide
Semiconductor, CMOS logic gates and
mechanically flexible transistors on
plastic provide examples of devices that
can be formed with this approach.
Multi-Walled Nanotube (MWNT)
Multi-walled nanotubes
(MWNTs) consist of multiple rolled
layers (concentric tubes) of graphene.
Structures of MWNTs can be describe
by two model which are Parchment
model and Russian Doll model. In

5. the Parchment model, a single sheet of
graphite is rolled in around itself,
resembling a rolled newspaper. The
interlayer distance in multi-walled
nanotubes is close to the distance
between graphene layers in graphite. In
the Russian Doll model, sheets of
graphite are arranged in concentric
cylinders, for example small single-
walled nanotube (SWNT) within a larger
single-walled nanotube.. The Russian
Doll structure is observed more
commonly. Its individual shells can be
described as SWNTs, which can be
metallic or semiconducting. MWNT is
usually a zero-gap metal due to the
statistical probability and restrictions on
the relative diameters of the individual
tubes.
Double-walled carbon nanotubes
(DWNTs) form a special class of
nanotubes because their properties are
similar to SWNTs but their resistivity to
chemicals are higher. This is important
when it is necessary to graft chemical
functions to the surface of the nanotubes
(functionalization) to add properties to
the CNT. Covalent functionalization of
SWNTs will break some C=C double
bonds, leaving "holes" in the structure
on the nanotube, and thus modifying
both its mechanical and electrical
properties. In the case of DWNTs, only
the outer wall is modified.
DWNT synthesis on the gram-
scale was first proposed in 2003 by
the combustion chemical vapor
deposition,CCVD technique, from the
selective reduction of oxide solutions in
methane and hydrogen. The telescopic
motion ability of inner shells and their
unique mechanical properties will permit
the use of multi-walled nanotubes as
main movable arms in coming
nanomechanical devices. Retraction
force that occurs to telescopic motion
caused by the Lennard-Jones
interaction between shells and its value
is about 1.5 nN.

6. SYNTHESIS CNT’s IN ELECTRONIC APPLICATIONS
4.0 Synthesis CNT in Electronic
Application
4.1 Synthesis of carbon nanotubes
This was a significant disadvantage of the
arc-discharge method for analysis on
nanotubes, until 1997, when Journetand his
co-workers found that the mixture 1 at.% Y
and 4.2 at.% Ni as stimulus in graphite
powder gave a high yield of 70-90% in their
setup . Iijima first discovered the multiwall
carbon nanotubes in 1991, when he worked
on C60 and witnessed carbon soot on the
negative graphite electrode produced in arc
discharge shown in Figure 1. In 1992,
Ebbesen and Ajayan effectuated growth and
purification ofmultiwalled carbon nanotubes
at the gram level using the arc-discharge
method. In 1993, Iijima'sgroup , as well as
Bethune and his associates found that the
utilisation of transitional-metal stimulus in
the arc-discharge process leads to nanotubes
with only a single shell. Another highlight in
the synthesis of single-walled carbon
nanotubes is the effort made by Smalley's
group in 1996. However, the yield of carbon
nanotubes was low, and there were large
amounts of metal carbide groups and
indefinite shape carbon attached to the
nanotubes. This method involves the
condensation of carbon atoms and radicals
from evaporation of solid carbon sources in
arc discharge, and the temperature involved
can be as high as 3000-4000 C. These
nanotubes mostly have diameters around 5-30
nm and lengths around 10m.
Figure 1. The transmission electron
microscope (TEM) image of first discovered
carbon nanotubes Iijima: the multiwalled
carbon nanotubes he found in the soot of an
arc-discharge setup.
In spite of the success of the arc-discharge
and laser ablation methods in producing
carbon nanotubes with a high yield, the final
products are usually bundled nanotubes
decorated with stimulus particles and
indefinite shape carbon. He and his co-
workers at Rice University developed a laser
ablation method that could grow single-
walled carbon nanotubes with a single-walled
carbon nanotubes with relatively high yield of
more than 70%, which paved the way for the
take-off of analysis on the physical properties
of SWNTs.
This method has been widely applied to
remove indefinite shape carbon and excess
catalytic metal particles commonly found
mixed with nanotubes in the final product.
They used the laser ablation on graphite rods
doped with a mixture of cobalt and nickel
powder in the environment followed by heat
treatment in vacuum to remove C60 and other
small fullerenes. Previous studies using such
products have been critically constrained by
the lack of control over the nanotube growth
and the difficulty in wiring up individual

7. nanotube devices, making practical uses
almost impossible.
A purification process involving refluxing the
as-grown nanotubes in a nitric acid for an
extended period was also developed by
Smalley and his co-workers.
It is equally desirable to develop a method to
make robust, low-resistance electrical
contacts between nanotubes and metallic
electrodes.
Figure 2 shows the experiment setup and the
bundled ropes generated by laser ablation
would be desirable to have a high-yield
generation route to produce SWNTs with
controlled length, positions, and orientations
for both scientific and technological studies.
The nanotubes they got had highly uniform
diameters and bundled together as "ropes" by
van der Waals interaction.
Figure 2. (a) The experimental setup of laser
ablation method to synthesize the SWNT.
The laser beam is focused on the carbon rod
doped with catalysts when flowing inertial
gas. The soot as the product is collected
at the copper collector.
Characteristic of carbon nanotubes can be
different as it depending on how graphene
sheet has rolled up to form the tube which can
make it to become metallic or semiconductor.
Carbon nanotubes can have many structures
which diferent in length, thickness and
number of layers. First, carbon nanotubes
(CNts) are unique due to the bonding between
the atoms is very strong.
1. Single-walled nanotubes (SWCNT)
A single-walled nanotubes give a look of
regular straw in shape. It only have one or
single wall or layer which fold in to
cylindrical shape.
2. multiple-walled nanotubes (MWCNT)
The multi-walled nanotubes give a look of
nested tubes of increasing in diameters. Its
structure can be categorized into inner and
outer tube and each tubes held some distance
from each other by a strong interatomic
forces.
Figure 3. shows single and multi-walled
CNTs
From the beginning, carbon nanotubes are
related to graphite. Carbon nanotubes are
members of the fullerene structural. Graphine
is a long, hollow structure with walls formed
by one atom thick sheets of carbon.
Figure 4. Schematic diagram of carbon
nanotubes made from rolled graphine sheet.
4.2 Properties of carbon nanotubes

8. From the characteristic of carbon nanotubes
above, we can know that the structure of
CNTs can influence its properties which are
electrical conductivity, thermal stability,
density and so on.
4.2.1 Electronic Properties of carbon
nanotubes
However, unlike nanowires based on ordinary
semiconductors, carbon nanotubes display
rich electronic properties, the most important
of which is that a carbon nanotube can be
metallic, semi-metallic, or semiconducting,
depending on its chirality and diameter [1,
38-42]. Band structure calculations have
foreseen that armchair SWNTs with (n , n)
indices are truly metallic with limited density
of states at the Fermi level, whereas SWNTs
with (m , n) indices are semiconducting when
m - n ≠ 3 x integer and have first primary
energy gaps Eg∝ 1/d, where d is the nanotube
diameter SWNTs with (m, n) indices and m -
n = 3 x integer are semi-metallic with zero
band gap within tight-binding calculations
based on pπ -orbitals alone. Research on the
electronic transport through single walled
carbon nanotubes went through enormous
progress in the past few years. This has been
mostly driven by the fascinating science and
many potential usages related to nanotubes.
Louie and co-workers have carried out first-
principles ab initio calculations and found
that the curvatures of small diameter SWNTs
can lead to rehybridization of π∗- and σ∗-
orbitals and thus manipulated electronic
structures of SWNTs from those of flat
graphene stripes. It was pointed out that the
curvature of nanotubes leads to nonparallel
π∗- orbitals interacting with σ∗- orbitals,
which causes the opening of a small bandgap
to result in an semiconductor from a
semimetal. The following sections will
review electronic transport studies on
metallic, semi-metallic, and alsosemi-
conducting nanotubes, with our focus on
results obtained from nanotube devices
generated via the CVD growth method.
For SGS-SWNTs, the bandgaps depend on
specific ( m - n ) indices and are in the range
of 2-50 meV for d = 3-0.7 nm.
4.2.2 Carbon nanotube strength and elasticity
The main atom in carbon nanotubes is carbon
atom in single ( graphene) sheet of graphite
form a planar lattice which have strong
bonding to their another neighbouring atoms.
From this, single-walled CNTs are stiffer than
steel and have strong resistant to any huge
physical outcome damage.
The plane elastic modulus of graphite is one
of the largest of any material due to this
strong bonding.
4.2.3 Carbon nanotube thermal conductivity
and expansion
The almost zero in-plane thermal expansion
but large inter-plane expansion of single-
walled carbon nanotubes give a strong
coupling and high flexibility against non-
axial strain.
CNTs have high thermal conductivity due to
the strong in-plane graphite c-c bonds make
them strong and stiffer against large strain.
4.2.4 Carbon nanotube high aspect ratio
Their high aspect ratio imparts electrical
conductivity at low loading when compared
to carbon black, chopped carbon fiber.
CNTs have high aspect ratio which low
loading preserves more of the polymer resins
especially at low temperatures.
4.3 Fabrication and overview of carbon
nanotubes
Making electrical contacts to individual
carbon nanotubes lies at the heart of nanotube
device production. A popular spin-on method
was developed by McEuen and his co-
workers, and Dekker and his co-workers.
Asmall amount of carbon nanotube material,
usually produced by laser ablation or arc
discharge, is first disseminate into an organic
solvent to form a suspension, and then spun
onto a Si/SiO2 layer with predefined metal

9. electrodes. Besides, atomic force microscopy
(AFM) is used to locate the nanotubes first
and e-beam lithography is then carried out to
define electrical contacts to the carbon
nanotubes. In contrast, the controlled CVD
method can directly grow individual carbon
nanotubes at desired position on Si/ SiO2
layer [22-25], as described in Section 2, and
therefore is superior in producing nanotube
devices and integrated systems.
This method is simple and easy to use
however, it has no control over the nanotube
location and alignment and the yield for good
devices is usually low.
AFM is usually employed to secure each
device consists of a single nanotube bridging
the metal electrodes.
The electronic measurements are usually
performed in the temperature range from 300
K downto 1.5 K and the heavily doped silicon
layer is used to supply the gate bias. The
length of the nanotubes between the
electrodes is controlled by the e-beam
lithography step and can change from 0.5 μm
to 5 μm. The first category corresponds to
nanotube devices with low resistance and
weak or no gate dependence, generally
regarded as the signature of metallic carbon
nanotubes.The second category corresponds
to devices with relatively low resistance;
however, change in the gate bias can bring
such devices from a conductive state to an
almost insulating state, and then back to a
conductive state.The third category
corresponds to devices with high resistance
and strong gate dependence, corresponding to
semiconducting nanotubes.Most of the carbon
nanotube devices fall into three categories
according to their resistance and gate
dependence.Such devices will be described in
detail in Section 3.3 and are attributed to
small-gap semiconducting (or semimetallic)
carbon nanotubes.
Figure 5. Bandgaps calculated for carbon
nanotubes of various diameters.The tubes fall
into three families: semiconducting nanotubes
with
primary gaps which scale as 1/R (top panel,
top curve), semimetallicnanotubes with zero
primary gap but nonzero curvature-induced
gapswhich scale as 1/R2 (top panel, lower
curve, and shown in the expanded
scale in the lower panel), and armchair tubes
with zero primary gapand zero curvature-
induced gap
Figure 6. Temperature-dependent resistance
of a metallic SWNT. Inset:
I-V and dI/dV−V curves recorded at 4 K.

10. 4.3.1 PURPOSE OF THE APPLICATION
Due to their high conductivity, high aspect
ratio, and natural tendency to form ropes,
MWCNTs are ideal in providing inherently
long conductive pathways even at ultra-low
loadings. The lower loading of additive can
offer several advantages such as better
processability polymer. This is why the use of
carbon nanotubes are well used for
conductive and antistatic applications in
sectors such as electronics and the automotive
industry. Concrete examples in the
automotive industry are fuel lines
(connectors, pump parts, o-rings, and fuel
systems components. Carbon fiber structural
composites and a thermoset have been
improved via development by the
introduction of carbon nanotubes. Further
more, CNT also plays important role in the
electronic industry, conveyor belts,
manufacturing tools and equipments, wafer
carriers, clean room equipments. Every sports
equipments on the market can be developed
by using CNT. Professional athletes are more
preferred to buy high-end models which
includes the characteristic such as more
durable and lighter weighted. For examples,
the famous national Finnish ice hockey team
is equipped with CNT reinforced sticks while
Federer the tennis champion is playing with
CNT reinforced rackets. These upcoming
structural composite materials based on CNT
reinforced thermoplastics or thermosets
combine strong mechanical properties and
low density and will direct a path to new
developments. These will particularly
replacing metals in various mechanical
applications where a weight reduction could
save energy, like in automotive industry.
Carbon Nanotubes may also play a role in the
modification of existing textile materials
using electrostatic self-assembly and atomic
layer deposition techniques to create novel
and customizable surfaces on conventional
textile materials with emphasis on natural
fibres. For example, the improvement of
mechanical properties in epoxy-glassfiber or
epoxy–carbon fiber composites already
known from the sport industry can also be
used in the construction of light weighted
composites for wind power generators and in
the aircraft industry.

11. ADVANTAGES & DISADVANTAGES
Advantages
It is improves the conductive,
mechanical and flame barrier
properties of plastics and
composites.
It is resistant to temperature changes,
meaning they function almost just as
well in extreme cold as they do in
extreme heat.
Extremely small and lightweight.
Resources required to produce are
plentiful and many of them can be
made with only a small amount of
material.
Disadvantages
The components are extremely
small, so are difficult to work
with.
The process to produce the
carbon nanotubes is quite
expensive.
In the research, most of the
scientists still do not understand
exactly how they work.

12. APPLICATIONS
Sensors and Probes
In this research, chemical sensor
applications of non-metallic nanotubes are
interesting because of nanotube electronic
transport and also thermos power which is
voltages between junctions caused by inter-
junction temperature differences that are
very sensitive to substances that affect the
amount of injected charge.
The mechanical robustness of the
nanotubes and the low buckling forces
dramatically increase probe life and
minimize the sample of damage during
repeated hard crashes into substrates. The
cylindrical shape and small tube diameter
enable imaging in narrow, deep crevices and
improve resolution in comparison to
conventional nanoprobes, especially for high
sample feature heights. Nanoscopic tweezers
have been made that are driven by the
electrostatic interaction between two
nanotubes on a probe tip.
Electrochemical Devices
Electronical devices is the high
electrochemically accessible surface area of
porous nanotube arrays, which combined
with their high electronic conductivity and it
is useful mechanical properties, these
materials are attractive as electrodes for
devices that use electrochemical double-
layer charge injection. For examples,
“supercapacitors” which have giant
capacitances in comparison with those of
ordinary dielectric-based capacitors, and
electromechanical actuators that may
eventually be used in robots. Like the others
capacitors, carbon nanotube supercapacitors
and electromechanical actuators actually
comprise two electrodes separated by an
electronically insulating material, which is
ionically conducting in electrochemical
devices.
The capacitance for an
electrochemically device depends on the
separation between the charge on the
electrode and the countercharge in the
electrolyte. When the separation is about a
nanometer for nanotubes in electrodes, as
compared with the micrometer or larger
separations in ordinary dielectric capacitors,
very large capacitances result from the high
nanotube surface area accessible to the
electrolyte.
The use of nanotubes as electrodes in
lithium batteries is a possibility because of
the high reversible component of storage
capacity at high discharge rates. The
maximum reported reversible capacity is
1000mA-hour/g for graphite and 708 mA-
hour/g for ball-milled graphite. However,
the large irreversible component to capacity
(coexisting with the large reversible storage
capacity), an absence of a voltage plateau
during discharge, and the large hysteresis in
voltage between charge and discharge
currently limit energy storage density and
energy efficiency, as compared with those of
other competing materials.
Hydrogen Storage
Carbon nanotube have the potentially
useful for hydrogen storage. For example,
for fuel cells that power electric vehicles.
However, experimental reports of high
storage capacities reported that it is
impossible to access the applications
potential.

13. RESULTS & DISCUSSIONS
5.0 Discussion
Carbon nanotubes are an extraordinary bit of
innovation, and new uses for them are being
found each day. Be that as it may they do
have their downsides.The disadvantages of
carbon nanotubes are :
i.Regardless of all the exploration,
researchers still don't see precisely how
they function
ii.Extremely little, so are hard to work with
iii.Currently, the procedure is moderately
costly to create the nanotubes
iv.Would be costly to execute this new
innovation in and supplant the more
established innovation in every one of the
spots that we could
v.At the rate our innovation has been getting
to be plainly out of date, it might be a bet to
wager on this innovation
Carbon nanotubes (CNTS) have unique
properties as they are quasi-one-dimension
materials and are ideal materials for
application in electronic devices. The main
reason for choosing carbon nanotubes as the
role material in electronic devices is that the
carbon atoms in carbon nanotubes are
strongly and firmly connected. Each atom
has three bonds to the other atoms, and all
these bonds are covalent bond

14. CONCLUSION
So in conclusion, carbon nanotubes
bring lots of benefits to mankind. Its
discovery was a miracle and also
revolutionize today’s electronic parts. As we
know, carbon nanotubes have unique
characteristics. These characteristics make it
so special, even other material cannot
compete with it. Carbon nanotubes are used
in many ways like sensors and probes,
electrochemical device and hydrogen
storage. Carbon nanotubes can be classified
into two part; single-walled nanotubes and
multi-walled nanotubes. Moreover, the
properties that shape up the CNTs are its
electronic properties, which is it consist of
metallic and semiconductor, its strength and
elasticity, where the CNTs is durable and
consist of high strength, its thermal
conductivity and expansion and lastly its
high aspect ratio. But despites its greatness,
everything have its pros and cons. For
carbon nanotubes, it has more pros than cons
such as small and lightweight. But to
produce these nanotubes, it need higher cost.
Thus, making a part using CNTs is very
expensive and costly. After synthesizing the
true meaning of carbon nanotubes and its
function, we can conclude that CNTs is one
of the greatest discovery and also bring lots
of improvement in electronic parts.

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