U.S. patent application number 11/473981 was filed with the patent office on 2007-05-24 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 Chi-Chuang Ho.
Application Number | 20070116634 11/473981 |
Document ID | / |
Family ID | 37877764 |
Filed Date | 2007-05-24 |
United States Patent
Application |
20070116634 |
Kind Code |
A1 |
Ho; Chi-Chuang |
May 24, 2007 |
Apparatus and method for manufacturing carbon nanotubes
Abstract
An exemplary apparatus includes a reaction chamber having a gas
inlet at a lower portion thereof configured for introducing a
carbon source gas thereinto and a gas outlet at an upper portion
thereof, the reaction chamber defining a carbon source gas flow
route, a substrate holder arranged between the gas inlet and gas
outlet in the reaction chamber, and at least one substrate having a
number of through holes defined therein configured for facilitating
the flowing of the carbon source gas therethrough and a catalyst
layer formed on a surface thereof facing the gas inlet, the at
least one substrate being positioned on the carbon source gas flow
route by the substrate holder.
Inventors: |
Ho; Chi-Chuang; (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: |
37877764 |
Appl. No.: |
11/473981 |
Filed: |
June 23, 2006 |
Current U.S.
Class: |
423/447.3 ;
422/129; 422/150 |
Current CPC
Class: |
D01F 9/133 20130101;
D01F 9/127 20130101; B82Y 30/00 20130101 |
Class at
Publication: |
423/447.3 ;
422/129; 422/150 |
International
Class: |
D01F 9/12 20060101
D01F009/12; D01C 5/00 20060101 D01C005/00 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 12, 2005 |
CN |
200510037283.8 |
Claims
1. An apparatus for manufacturing carbon nanotubes, comprising: a
reaction chamber having a gas inlet at a lower portion thereof
configured for introducing a carbon source gas thereinto and a gas
outlet at an upper portion thereof, the reaction chamber defining a
carbon source gas flow route; a substrate holder arranged between
the gas inlet and gas outlet in the reaction chamber; and at least
one substrate having a plurality of through holes defined therein
configured for facilitating the flowing of the carbon source gas
therethrough and a catalyst layer formed on a surface thereof
facing the gas inlet, the at least one substrate being positioned
on the carbon source gas flow route by the substrate holder.
2. The apparatus as described in claim 1, wherein the at least one
substrate is oriented perpendicular to the carbon source gas flow
route.
3. The apparatus as described in claim 1, wherein a diameter of
each of the through holes is in a range from 0.5 microns to 1
micron.
4. The apparatus as described in claim 1, wherein the substrate
holder comprises at least one post, and the at least one substrate
defines at least one engaging hole, the at least one substrate is
secured to the substrate holder by extension of the at least one
post through the at least one engaging hole.
5. The apparatus as described in claim 1, wherein the substrate
holder defines a plurality of through holes aligned with respect to
the through holes of the at least one substrate.
6. A method for manufacturing carbon nanotubes, the method
comprising the steps of: (a) providing a substrate having a
plurality of through holes defined therein and a catalyst layer
formed on a first surface thereof; (b) orienting and positioning
the substrate in a manner such that the first surface of the
substrate faces downwardly; (c) supplying and directing a carbon
source gas to flow vertically from the first surface to an opposite
second surface of the substrate for growing carbon nanotubes
thereon by a chemical vapor deposition method.
7. The method as described in claim 6, wherein the carbon source
gas is comprised of a material selected from the group consisting
of methane, acetylene, ethylene, carbon monoxide and a mixture
thereof.
8. The method as described in claim 6, wherein the through holes of
the substrate are defined by a photolithography method.
9. The method as described in claim 8, wherein the through holes of
the substrate are defined by a drilling method.
10. The method as described in claim 6, wherein a diameter of each
of the through holes is in a range from 0.5 microns to 1
micron.
11. The method as described in claim 6, wherein the catalyst layer
is formed by a method selected from the group consisting of ion
plating, radio frequency magnetron sputtering, vacuum evaporation,
and chemical vapor deposition.
12. The method as described in claim 6, wherein the catalyst layer
is comprised a material selected from the group consisting of iron,
cobalt, nickel, and any appropriate combination alloy thereof.
13. A method for manufacturing carbon nanotubes, comprising the
steps of: (a) providing a reaction chamber having a gas inlet and a
gas outlet at a bottom and a top thereof respectively and a
substrate holder arranged therein, and the substrate holder having
at least one post; (b) providing a plurality of substrates each
having at least one engaging holes, a plurality of through holes
defined therein and a catalyst layer formed on a surface thereof;
(c) placing the substrates on the substrate holder with the
catalyst layer facing the gas inlet and the at least one post of
the substrate holder extending through the at least one engaging
holes of the substrates, the substrates being spaced apart from
each other; (d) supplying a carbon source gas into the reaction
chamber through the gas inlet for growing carbon nanotubes by a
chemical vapor deposition method.
14. The method as described in claim 13, wherein the substrate
holder defines a plurality of through holes aligned with respect to
the through holes of the at least one substrate.
15. The method as described in claim 13, wherein the carbon source
gas is comprised of a material selected from the group consisting
of methane, acetylene, ethylene, carbon monoxide and a mixture
thereof.
16. The method as described in claim 13, wherein the substrates are
spaced from each other by a plurality of washers.
17. The method as described in claim 13, wherein a diameter of each
of the through holes is in the range from 0.5 microns to 1
micron.
18. The method as described in claim 13, wherein the catalyst layer
is formed by a method selected from the group consisting of ion
plating, radio frequency magnetron sputtering, vacuum evaporation,
and chemical vapor deposition.
19. The method as described in claim 13, wherein the catalyst layer
is comprised of a material selected from the group consisting of
iron, cobalt, nickel, and any combination alloy thereof.
Description
TECHNICAL FIELD
[0001] The present invention relates to apparatuses and methods for
manufacturing carbon nanotubes, and particularly to an apparatus
and method for manufacturing carbon nanotubes by a chemical vapor
deposition method.
DISCUSSION OF RELATED ART
[0002] Carbon nanotubes are tubules of carbon generally having a
length of 5 to 100 micrometers and a diameter of 5 to 100
nanometers. Carbon nanotubes are composed of a number of co-axial
cylinders of graphite sheets and have recently received a great
deal of attention for use in different fields such as field
emitters, gas storage and separation, chemical sensors and high
strength composites. Carbon nanotubes have many promising
properties such as a high strength and low weight, high energy and
fuel storage capability, good electron emission capability and many
advantageous thermal, chemical and surface properties.
[0003] Currently there are three principal methods to manufacture
carbon nanotubes, namely arc discharge, laser ablation and chemical
vapor deposition. Among these, the chemical vapor deposition method
is perhaps most widely used.
[0004] A general apparatus for manufacturing carbon nanotubes with
a chemical vapor deposition method includes a reaction furnace and
a substrate with a catalyst layer thereon in the reaction furnace.
A process for manufacturing carbon nanotubes with above-described
apparatus includes the steps of:
[0005] (1) providing a substrate with a catalyst layer and placing
it in the reaction furnace;
[0006] (2) heating the reaction furnace to a predetermined
temperature;
[0007] (3) supplying a carbon source gas into the reaction furnace
and growing carbon nanotubes by a chemical vapor deposition
method.
[0008] Such a manufacturing process suffers from the disadvantage
that the growth direction of carbon nanotubes is affected by the
flow direction of the gas, so the alignment of carbon nanotubes is
not good.
[0009] What is needed, therefore, is an apparatus and method for
manufacturing aligned carbon nanotubes.
SUMMARY
[0010] An apparatus and method for manufacturing aligned carbon
nanotubes according to a preferred embodiment is provided.
[0011] The apparatus includes a reaction chamber having a gas inlet
at a lower portion thereof configured for introducing a carbon
source gas into the reaction chamber with a gas outlet in an upper
portion thereof, the reaction chamber defining a carbon source gas
flow route, a substrate holder arranged between the gas inlet and
gas outlet in the reaction chamber, and at least one substrate
having a number of through holes defined therein configured for
facilitating the flow of carbon source gas therethrough and a
catalyst layer formed on a surface thereof facing the gas inlet,
the at least one substrate being positioned in the carbon source
gas flow route by the substrate holder.
[0012] The method includes the steps of:
[0013] (a) providing a substrate having a number of through holes
defined therein and a catalyst layer formed on a first surface
thereof;
[0014] (b) orienting and positioning the substrate in a manner such
that the first surface of the substrate faces downwardly;
[0015] (c) supplying and directing a carbon source gas to flow
vertically from the first surface to an opposite second surface of
the substrate for growing carbon nanotubes thereon by a chemical
vapor deposition method.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The features and advantages of the present apparatus and
method for manufacturing carbon nanotubes, and the manner of
attaining them, will become more apparent and the invention will be
better understood by reference to the following description of
embodiments thereof taken in conjunction with the accompanying
drawings.
[0017] FIG. 1 is a schematic, front view of an apparatus for
manufacturing carbon nanotubes in accordance with a first preferred
embodiment of the present invention;
[0018] FIG. 2 is schematic, top view of a substrate of the
apparatus in accordance with the first preferred embodiment of the
present invention;
[0019] FIG. 3 is a schematic, front view of an apparatus for
manufacturing carbon nanotubes in accordance with a second
preferred embodiment of the present invention;
[0020] FIG. 4 is schematic, top view of a substrate holder of the
apparatus in accordance with the second preferred embodiment of the
present invention.
[0021] FIG. 5 is schematic, top view of a substrate of the
apparatus in accordance with the second preferred embodiment of the
present invention.
[0022] FIG. 6 is a schematic, front view of an apparatus for
manufacturing carbon nanotubes in accordance with a third preferred
embodiment of the present invention; and
[0023] FIG. 7 is schematic, top view of a substrate of the
apparatus in accordance with the second preferred embodiment of the
present invention.
[0024] Corresponding reference characters indicate corresponding
parts throughout the several views. The exemplifications set out
herein illustrate at least one preferred embodiment of the present
apparatus and method for manufacturing carbon nanotubes, in one
form, and such exemplifications are not to be construed as limiting
the scope of the invention in any manner.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0025] Reference will now be made to the drawings to describe in
detail the preferred embodiments of the present apparatus and
method for manufacturing carbon nanotubes.
[0026] Referring to FIG. 1, an apparatus 100 for manufacturing
carbon nanotubes according to a first preferred embodiment is
shown. The apparatus 100 includes a reaction chamber 110, a heating
device 120, and a substrate 130.
[0027] The reaction chamber 110 has a gas inlet 112, a gas outlet
114 and a substrate holder 116. The gas inlet 112 is configured at
a bottom of the reaction chamber 110 for introducing a carbon
source gas into the reaction chamber 110. The gas outlet 114 is
configured at a top of the reaction chamber 110 for outputting gas.
Preferably, the gas outlet 14 is directly opposite to the gas inlet
112, thus a reaction gas input from the gas inlet 112 can flow
directly from the bottom of the reaction chamber 110 to the top of
the reaction chamber 110. The substrate holder 116 is arranged
between the gas inlet 112 and gas outlet 114 in the reaction
chamber 110 for holding the substrate 130. As such, the reaction
gas can flow through an area for holding the substrate 130 in a
direction substantially parallel to a growth direction of carbon
nanotubes.
[0028] The heating device 120 is configured adjacent the reaction
chamber 110 for heating the reaction chamber 110. In this
embodiment, the heating device 120 is disposed around the reaction
chamber 110. The heating device 120 may be high temperature
furnace, high frequency furnace etc.
[0029] The substrate 130 is held on the substrate holder 116.
[0030] Referring to FIG. 2, the substrate 130 defines a number of
through holes 132 for facilitating the flowing of reaction gas
therethrough. The through holes 132 can be distributed irregularly
or regularly in the substrate 130. A diameter of each of the
through holes 132 may be in a range from 0.5 microns to 1 micron. A
catalyst layer 134 is formed on a surface of the substrate for
growing carbon nanotubes. The catalyst layer 134 can be composed of
a catalyst material used for growth of carbon nanotubes, such as
iron, cobalt, nickel etc.
[0031] A method for manufacturing carbon nanotubes using the
apparatus 100 according to an aspect of present invention includes
the steps in no particular order of:
[0032] (a) a substrate 130 is provided, and a number of the through
holes 132 are defined therein and a catalyst layer 134 is formed on
a first surface thereof;
[0033] (b) the substrate 130 is oriented and positioned in a manner
such that the first surface of the substrate 130 faces
downwardly;
[0034] (c) a carbon source gas is supplied and directed to flow
vertically from the first surface to an opposite second surface of
the substrate 130 for growing carbon nanotubes thereon by a
chemical vapor deposition method.
[0035] In the step (a), the through holes 132 can be made using a
photolithography method, and in the present embodiment they are
formed using a drilling method. A diameter of each of the through
holes 132 is in a range from 0.5 microns to 1 micron. The catalyst
layer 134 can be formed using a method selected from the group
consisting of ion plating, radio frequency magnetron sputtering,
vacuum evaporation, and chemical vapor deposition.
[0036] In the step (b), the first surface of the substrate 130
faces downwardly so as to make the growth direction of carbon
nanotubes consistent with gravitational pull.
[0037] In the step (c), the catalyst layer 134 is first heated to
500.about.900.degree. C. with a heating device 120 such as high
temperature furnace or high frequency furnace around the reaction
chamber 110; a mixed gas including carbon source gas such as
methane, acetylene, ethylene, carbon monoxide or a mixture thereof
and protective gas such as helium, argon, hydrogen, or ammonia are
then supplied; the carbon source gas is cracked at the catalyst
layer 134 to grow carbon nanotubes.
[0038] Referring to FIGS. 3-5, an apparatus 200 for manufacturing
carbon nanotubes according to a second embodiment is shown. Similar
to the apparatus 100 of the first embodiment, the apparatus 200
includes a reaction chamber 210 and a heating device 220 around the
reaction chamber 210, wherein the reaction chamber 210 defines a
gas inlet 212 configured at a bottom of the reaction chamber 210
and a gas outlet 214 configured at a top of the reaction chamber
210. The difference between apparatus 200 and apparatus 100 is that
the substrate holder 216 has a post 2162 extending upwardly for
supporting a number of substrates 230 thereon and a number of
through holes 2164 aligned therein with respect to the through
holes 232 of the substrates 230 in an area opposite to the at least
one substrate for facilitating reaction gas therethrough, and a
number of washers 400 surrounding the post 2162 to separate the
substrates 230 from each other. Each of the substrates 230 has an
engaging hole 236 spatially corresponding to the post 2162. As
such, the substrates 230 are secured to the substrate holder by
extension of the post 2162 through the engaging hole 236.
[0039] A method for manufacturing carbon nanotubes with the
apparatus 200 of the second preferred embodiment is described in
detail as follows:
[0040] (1) a number of substrates 230 are provided, and a engaging
holes 236 and a number of through holes 232 arc formed in each of
the substrates 230, and a catalyst layer 234 formed on a first
surface of each of the substrates 230;
[0041] (2) the substrates 230 are placed on the substrate holder
216;
[0042] (3) a carbon source gas is supplied into the reaction
chamber 210 through the gas inlet 212 from bottom to top and
growing carbon nanotubes by a chemical vapor deposition method.
[0043] In the step (2), the substrates 230 are secured to the
substrate holder 216 by the post 2162 of the substrate holder 216
extending through the engaging hole 236 in series with a
predetermined space, and the substrates 230 are spaced apart from
each other. Generally the space is greater than the growth height
of carbon nanotubes. In the present embodiment, the substrates 230
are spaced from each other by a number of washers 400. The catalyst
layer 234 of each of the substrates 230 faces the gas inlet 212 to
make the growth direction of carbon nanotubes consistent with
gravitational pull.
[0044] Referring to FIG. 6 and FIG. 7, an apparatus 300 for
manufacturing carbon nanotubes according to a third embodiment is
shown. Similar to the apparatus 100 of the first embodiment, the
apparatus 300 includes a reaction chamber 310 and a heating device
320 around the reaction chamber 310, wherein the reaction chamber
310 defines a gas inlet 312 configured at a bottom of the reaction
chamber 310 and a gas outlet 314 configured at a top of the
reaction chamber 310. However, the substrate holder 316 has a
couple of posts 3162 extending upwardly for supporting a number of
substrates 330 thereon, and a number of washers 500 surrounding
each of the posts 2162 to separate the substrates 230 from each
other. Each of the substrates 330 has a couple of engaging holes
336 for engaging a corresponding couple of posts 3162. As such, the
couple of posts 3162 can extend through the engaging holes 336 so
as to hold the substrates 330 thereon.
[0045] A method for manufacturing carbon nanotubes with the
apparatus 300 of the third preferred embodiment is described in
detail as follows:
[0046] (1) a reaction chamber 310 having a gas inlet 312 and a gas
outlet 314 at a bottom and a top thereof respectively is provided,
a substrate holder 316 arranged therein, and the substrate holder
316 having a couple of posts 3162;
[0047] (2) a number of substrates 330 are provided, and a couple of
engaging holes 336 and a number of through holes 332 are formed in
each of the substrates 330, and a catalyst layer 334 is formed on a
surface of each of the substrates 330;
[0048] (3) the substrates 330 are placed on the substrate holder
316;
[0049] (4) a carbon source gas is supplied into the reaction
chamber 310 through the gas inlet 312 from bottom to top and
growing carbon nanotubes by a chemical vapor deposition method.
[0050] In the step (3), The substrates 330 are secured to the
substrate holder 316 by the post 3162 of the substrate holder 316
extending through the engaging hole 336 in series with a
predetermined space, and the substrates 330 are spaced apart from
each other. Generally the space is greater than the growth height
of carbon nanotubes. In the present embodiment, the substrates 330
are spaced from each other by a number of washers 500. The catalyst
layer 334 of each of the substrates 330 faces the gas inlet 312 to
make the growth direction of carbon nanotubes consistent with
gravity direction of that
[0051] An advantage of the above-described apparatuses are that the
catalyst layer of the substrates face the gas inlet and are
orientated with the flow direction of the carbon source gas so as
to manufacture aligned carbon nanotubes under gravity.
[0052] Another advantage of the above-described apparatuses are
that a number of substrates having a number of through holes
therein can be spaced on the substrate holder according to a
predetermined space so as to mass-produce aligned carbon
nanotubes.
[0053] While the present invention has been described as having
preferred or exemplary embodiments, the embodiments 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 embodiments using the general principles of the
invention as claimed. Furthermore, this application is intended to
cover such departures from the present disclosure as come within
known or customary practice in the art to which the invention
pertains and which fall within the limits of the appended claims or
equivalents thereof.
* * * * *