U.S. patent application number 11/402468 was filed with the patent office on 2007-04-26 for apparatus and method for manufacturing carbon nanotubes.
This patent application is currently assigned to HON HAI Precision Industry CO., LTD.. Invention is credited to Bor-Yuan Hsiao.
Application Number | 20070092430 11/402468 |
Document ID | / |
Family ID | 37985580 |
Filed Date | 2007-04-26 |
United States Patent
Application |
20070092430 |
Kind Code |
A1 |
Hsiao; Bor-Yuan |
April 26, 2007 |
Apparatus and method for manufacturing carbon nanotubes
Abstract
An apparatus for manufacturing carbon nanotubes is provided. The
apparatus includes a reaction chamber having a first inlet
configured for introducing a carbon-containing gas thereinto and a
first outlet; a heater for elevating an interior temperature of the
reaction chamber, wherein the reaction chamber is configured for
accommodating a substrate and the first inlet defines a route for
channeling the introduced carbon-containing gas toward the
substrate, the route being substantially perpendicular to a main
plane of the substrate.
Inventors: |
Hsiao; Bor-Yuan; (Tu-Cheng,
TW) |
Correspondence
Address: |
PCE INDUSTRY, INC.;ATT. CHENG-JU CHIANG JEFFREY T. KNAPP
458 E. LAMBERT ROAD
FULLERTON
CA
92835
US
|
Assignee: |
HON HAI Precision Industry CO.,
LTD.
Tu-Cheng City
TW
|
Family ID: |
37985580 |
Appl. No.: |
11/402468 |
Filed: |
April 12, 2006 |
Current U.S.
Class: |
423/447.3 |
Current CPC
Class: |
B01J 2219/00139
20130101; B82Y 40/00 20130101; B01J 2219/00135 20130101; D01F 9/133
20130101; B01J 2219/182 20130101; B82Y 30/00 20130101; B01J 4/002
20130101; C01B 32/162 20170801; C01B 2202/08 20130101; B01J
2219/1942 20130101; B01J 19/26 20130101; B01J 2219/1941 20130101;
D01F 9/127 20130101; B01J 2219/00132 20130101 |
Class at
Publication: |
423/447.3 |
International
Class: |
D01F 9/12 20060101
D01F009/12 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 21, 2005 |
CN |
200510100587.4 |
Claims
1. An apparatus for manufacturing carbon nanotubes, the apparatus
comprising: a reaction chamber having a first inlet configured for
introducing a carbon-containing gas thereinto, and a first outlet;
and a heater for elevating an interior temperature of the reaction
chamber, wherein the reaction chamber is configured for
accommodating a substrate and the first inlet defines a route for
channeling the introduced carbon-containing gas toward the
substrate, the route being substantially perpendicular to a main
plane of the substrate.
2. The apparatus for manufacturing carbon nanotubes according to
claim 1, wherein the reaction chamber has a shape selected from a
group consisting of substantially semi-conical and hemispheric.
3. The apparatus for manufacturing carbon nanotubes according to
claim 1, wherein the first inlet is configured at a top of the
reaction chamber and spatially corresponding to the substrate, and
the first outlet is configured adjacent to a bottom of the reaction
chamber.
4. The apparatus for manufacturing carbon nanotubes according to
claim 1, further comprising a gas guiding member for guiding the
gas to flow perpendicularly toward the substrate.
5. The apparatus for manufacturing carbon nanotubes according to
claim 4, wherein the gas guiding member comprises a inverted-funnel
portion having a narrow opening coupled to the first inlet and an
opposite wide opening spatially corresponding to the substrate.
6. The apparatus for manufacturing carbon nanotubes according to
claim 4, wherein the gas guiding member comprises a hemispherical
portion having a narrow opening coupled to the first inlet and an
opposite wide opening spatially corresponding to the substrate.
7. The apparatus for manufacturing carbon nanotubes according to
claim 1, further comprising a quartz tube, wherein the reaction
chamber is received in the quartz tube, the quartz tube has a
second inlet in communication with the first inlet and a second
outlet in communication with the first outlet.
8. The apparatus for manufacturing carbon nanotubes according to
claim 7, further comprising a gas guiding pipe, wherein the second
inlet is in communication with the first inlet via the gas guiding
pipe.
9. The apparatus for manufacturing carbon nanotubes according to
claim 7, wherein the quartz tube is received in the heater.
10. A method for manufacturing carbon nanotubes, the method
comprising the steps of: placing a substrate with a catalyst layer
formed thereon in to a reaction chamber; introducing a carrier gas
into the reaction chamber; heating the reaction chamber to a
predetermined temperature; introducing a carbon-containing gas into
the reaction chamber and directing the carbon-containing gas to
flow toward to the substrate along a direction that is
substantially perpendicular to a main plane of the substrate.
11. The method for manufacturing carbon nanotubes according to
claim 10, wherein the carrier gas is selected from the group
consisting of hydrogen gas, nitrogen gas, ammonia gas, and the like
inert gases.
12. The method for manufacturing carbon nanotubes according to
claim 10, wherein the predetermined temperature is in the range
from 500.degree. C. to 900.degree. C.
13. The method for manufacturing carbon nanotubes according to
claim 10, wherein the carbon-containing gas is selected from a
group consisting of methane, ethane, ethylene, acetylene and a
combination thereof.
Description
BACKGROUND
[0001] 1. Technical Field
[0002] The present invention relates to carbon nanotubes, and more
particularly to an apparatus and method for manufacturing carbon
nanotubes by chemical vapor deposition (CVD).
[0003] 2. Discussion of Related Art
[0004] Generally, it has been known that carbon nanotubes can be
manufactured by methods including resistance heating, plasma
discharge such as arc discharge with a carbon rod as a raw
material, laser ablation, and chemical vapor deposition using
acetylene gas.
[0005] Chemical vapor deposition is a method of generating carbon
nanotubes by a chemical decomposition reaction of the
carbon-containing gas, using acetylene gas, methane gas, or the
like containing carbon as a raw material. The chemical vapor
deposition depends on a chemical reaction occurring in the
carbon-source gas as part of a thermal decomposition process,
thereby enabling the manufacture of high-purity carbon nanotubes.
As shown in FIG. 3, a typical CVD apparatus 10 includes a
horizontally disposed quartz tube 30 configured to accommodate a
substrate 20, upon which nanotubes can be grown. The quartz tube 30
has an inlet 32 and a corresponding outlet 34. The substrate 20 has
a catalyst layer 22 formed on a top surface thereof. During
nanotube growth, a flow of carbon-containing gas is horizontally
provided to move along and inside the quartz tube 30, thereby
bringing carbon elements contained in the gas to the substrate
20.
[0006] However, carbon nanotubes formed by the above-mentioned
apparatus have shortcomings. During the manufacturing process, the
direction of the gas flow is substantially parallel with the
surface of the catalyst layer, while the nanotubes grow upwardly
perpendicular to the catalyst layer 22. As such, although rather
slow, the horizontal movement of the flow disturbs the growing
process of the nanotubes and alters the vertical alignment of the
carbon nanotubes.
[0007] Therefore, what is needed in the art is to provide an
apparatus for manufacturing vertically aligned carbon
nanotubes.
SUMMARY
[0008] In one aspect of the present invention, an apparatus for
manufacturing carbon nanotubes is provided. The apparatus includes:
a reaction chamber having a first inlet configured for introducing
a carbon-containing gas thereinto, a first outlet, a heater for
elevating an interior temperature of the reaction chamber, wherein
the reaction chamber is configured for accommodating a substrate
and the first inlet defines a route for channeling the introduced
carbon-containing gas toward the substrate, the route being
substantially perpendicular to a main plane of the substrate.
[0009] In another aspect of the present invention, a method for
manufacturing carbon nanotubes is provided. The method includes the
steps of: placing a substrate with a catalyst layer formed thereon
in to a reaction chamber; introducing a carrier gas into the
reaction chamber; heating the reaction chamber to a predetermined
temperature; introducing a carbon-containing gas into the reaction
chamber and directing the carbon-containing gas to flow toward to
the substrate along a direction that is substantially perpendicular
to a main plane of the substrate.
[0010] Detailed features of the present carbon nanotubes
manufacturing apparatus will become more apparent from the
following detailed description and claims, and the accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Many aspects of the present apparatus and method can be
better understood with reference to the following drawings. The
components in the drawings are not necessarily drawn to scale, the
emphasis instead being placed upon clearly illustrating the
principles of the present apparatus and method. Moreover, in the
drawings, like reference numerals designate corresponding parts
throughout the several views, wherein:
[0012] FIG. 1A is a schematic cross-sectional view of an apparatus
for manufacturing carbon nanotubes according to a first exemplary
embodiment.
[0013] FIG. 1B is a schematic cross-sectional view of a
substantially cube-shaped reaction chamber of the apparatus
illustrated in FIG. 1A.
[0014] FIG. 1C is a schematic cross-sectional view of a semi-cone
reaction chamber of an apparatus for manufacturing carbon nanotubes
according to a second embodiment.
[0015] FIG. 1D is a schematic cross-sectional view of a
hemispherical reaction chamber of an apparatus for manufacturing
carbon nanotubes according to a third embodiment.
[0016] FIG. 2A is a schematic cross-sectional view of an apparatus
for manufacturing carbon nanotubes according to a fourth exemplary
embodiment.
[0017] FIG. 2B is a schematic cross-sectional view of a reaction
chamber with a inverted-funnel shaped gas guiding member of the
apparatus illustrated in FIG. 2A.
[0018] FIG. 2C is a schematic cross-sectional view of a reaction
chamber with a hemispherical gas guiding member of an apparatus for
manufacturing carbon nanotubes according to a fifth embodiment.
[0019] FIG. 3 is a schematic cross-sectional view of a typical
apparatus for manufacturing carbon nanotubes.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0020] Reference will now be made to the drawings to describe the
preferred embodiments of the present apparatus for manufacturing
carbon nanotubes, in detail.
[0021] Referring now particularly to FIG. 1A, where an apparatus 40
for manufacturing carbon nanotubes according to a first embodiment
of the present invention is shown. The apparatus 40 mainly includes
a reaction chamber 60 and a heater 70. A substrate 50 is disposed
in the reaction chamber 60. The heater 70 is configured for heating
the interior of the reaction chamber 60.
[0022] The substrate 50 has a catalyst layer 52 formed on a top
surface thereof. The substrate 50 is made of a material selected
from a group consisting of quartz, silicon, and magnesium oxide.
The material of the catalyst layer 52 is selected from a group
consisting of cobalt, nickel, iron, and any appropriate alloy of
them.
[0023] In the first embodiment, the reaction chamber 60 is a cubic
chamber as shown in FIG. 1B. Alternately, the reaction chamber 60
could have other shapes, i.e., substantially semi-conical in a
second embodiment or hemispheric in a third embodiment, as shown in
FIG. 1C and FIG. 1D respectively. Referring to FIG. 1B, the
reaction chamber 60 has a first inlet 62 and a first outlet 64. The
first inlet 62 is configured in a top of the reaction chamber 60
spatially corresponding to the substrate 50. The first outlet 64 is
configured to be adjacent to a bottom of the reaction chamber 60.
Alternately, the first outlet 64 could also be formed at the bottom
of the reaction chamber 60.
[0024] Additionally, the reaction chamber 60 is received in a
quartz tube 80 that has a second inlet 82 at one end portion and a
second outlet 84 at another end portion. The second inlet 82 is in
communication with the first inlet 62 and the second outlet 84 is
in communication with the first outlet 64. In the illustrated
exemplary embodiment, the second inlet 82 is in communication with
the first inlet 62 via a gas guiding pipe 86.
[0025] The heater 70 can be any type of heating device that is
adapted for heating the reaction chamber 60, for example a high
temperature furnace or a high frequency induction heating furnace
can be used.
[0026] In another aspect of the present invention, a method for
manufacturing carbon nanotubes comprises the steps in no particular
order of: [0027] (1) placing a substrate 50 that with has a
catalyst layer 52 formed thereon in to a reaction chamber 60;
[0028] (2) introducing a carrier gas into the reaction chamber 60;
[0029] (3) heating the reaction chamber 60 to a predetermined
temperature; [0030] (4) introducing a carbon-containing gas into
the reaction chamber 60 and directing the carbon-containing gas to
flow toward to the substrate 50 along a direction that is
substantially perpendicular to a main plane of the substrate
50.
[0031] In step (1), the substrate 50 with a catalyst layer 52
formed thereon is fed into the reaction chamber 60.
[0032] In step (2), a carrier gas is introduced into the reaction
chamber 60. In the illustrated exemplary embodiment, the carrier
gas is supplied to the second inlet 82, then the carrier gas is
transported successively passing through the gas guiding pipe 86,
the first inlet 62. Thereafter, the carrier gas is discharged into
the reaction chamber 60. The carrier gas is selected from the group
consisting of hydrogen gas, nitrogen gas, ammonia gas, and
similarly inert gases.
[0033] In step (3), the reaction chamber 60 is heated to a
predetermined temperature by the heater 70. Specifically, the
predetermined temperature is in the range from 500.degree. C. to
900.degree. C.
[0034] In step (4), the carbon-containing gas is introduced through
the second inlet 82 for a certain time so as to grow carbon
nanotubes on the substrate 50. The carbon-containing gas is
selected from a group consisting of methane, ethane, ethylene,
acetylene and similar carbon containing gases.
[0035] During the above-described process of manufacturing carbon
nanotubes, the moving direction of the flow of carbon-containing
gas is generally perpendicular to the surface of the catalyst
layer, and is thus greatly advantageous for the vertical growth of
carbon nanotubes. So the apparatus provided in the exemplary
embodiment can be used to manufacture carbon nanotubes with high
vertically oriented alignment.
[0036] An apparatus 400 according to the fourth embodiment, as
shown in FIG. 2A, is described as follows. The apparatus 400 mainly
includes a reaction chamber 600 and a heater 700. A substrate 500
is received and disposed in the reaction chamber 600. The heater
700 is configured for heating the interior of the reaction chamber
600.
[0037] Similar to the substrate 50 shown in FIG. 1A, the substrate
500 shown in FIG. 2A has a catalyst layer 520 formed on a top
surface thereof. The substrate 500 is made of a material selected
from a group consisting of quartz, silicon, and magnesium oxide.
The material of the catalyst layer 520 is selected from a group
consisting of cobalt, nickel, iron, and any appropriate alloy of
them.
[0038] The reaction chamber 600 is a substantially cube-shaped
chamber as shown in FIG. 2B. The reaction chamber 600 has a first
inlet 620, a first outlet 640 and a gas guiding member 660. The
first inlet 620 is configured at a top of the reaction chamber 600
and spatially corresponding to the substrate 500. The first outlet
640 is configured adjacent to a bottom of the reaction chamber 600.
Alternately, the first outlet 640 can also be formed at the bottom
of the reaction chamber 600. The gas guiding member 660 is a shell
portion that has a shape of inverted-funnel as shown in FIG. 2B.
The gas guiding member 660 comprises a narrow opening coupled to
the first inlet 620 and an opposite wide opening spatially
corresponding to the substrate 500. Alternately, the gas guiding
member 660 could also be a shell portion having other shapes, for
example, hemispherical in a fifth embodiment as shown in FIG.
2C.
[0039] Additionally, the reaction chamber 600 is received in a
quartz tube 800 that has a second inlet 820 at one end portion and
a second outlet 840 at another end portion. The second inlet 820 is
in communication with the first inlet 620 and the second outlet 840
is in communication with the first outlet 640. In the illustrated
exemplary embodiment, the second inlet 820 is in communication with
the first inlet 620 via a gas guiding pipe 860.
[0040] The heater 700 can be any type of heating device that is
adapted for heating the reaction chamber 600, for example, a high
temperature furnace or a high frequency induction heating
furnace.
[0041] While this invention has been described as having a
preferred design, the present invention can be further modified
within the spirit and scope of this disclosure. This application is
therefore intended to cover any variations, uses, or adaptations of
the invention using its general principles. Further, this
application is intended to cover such departures from the present
disclosure as come within known or customary practice in the art to
which this invention pertains and which fall within the limits of
the appended claims.
* * * * *