Free Atom Nanotube Growth

Abstract

Disclosed is a free atom nanotube growth technology capable of continuously growing long, high quality nanotubes. This patent application is a Continuation In Part of the Trekking Atom Nanotube Growth patent application #14037034 filed on Sep. 25, 2013. The current invention represents a departure from chemical vapor deposition technology as the atomic feedstock does not originate in the gaseous environment surrounding the nanotubes. The technology mitigates the problems that cease carbon nanotube growth in chemical vapor deposition growth techniques: 1) The accumulation of material on the surface of the catalyst particles, suspected to be primarily amorphous carbon, 2) The effect of Ostwald ripening that reduces the size of smaller catalyst particles and enlarges larger catalyst particles, 3) The effect of some catalyst materials diffusing into the substrate used to grow carbon nanotubes and ceasing growth when the catalyst particle becomes too small.

Claims

1. An apparatus for nanotube growth comprising: an emrad source capable of emitting emrad that can liberate a feedatom to migrate; a substrate capable of transmitting emrad from the back side to the front side; a feedlayer on the front side of the substrate capable of absorbing the emrad; feedatoms in the feedlayer capable of being liberated, by absorbing emrad, to migrate; a catalyst layer on the front side of the feedlayer capable of growing nanotubes with feedatoms; and an ineratmo that is the environment adjacent to the front side of the feedlayer.

2. The apparatus for nanotube growth according to claim 1, wherein the catalyst layer is replaced with catpars.

3. The apparatus for nanotube growth according to claim 1, wherein the emrad source illuminates the substrate assembly from the front side rather than the backside.

4. The apparatus for nanotube growth according to claim 1, wherein a feedvoir replaces the feedlayer.

5. The apparatus for nanotube growth according to claim 1, wherein the emrad source, separate from the substrate, is selected from the group consisting of a laser, a light emitting diode lamp, a fluorescent lamp, or an incandescent lamp.

6. The apparatus for nanotube growth according to claim 1, wherein the emrad source, fabricated as a part of the substrate, is selected from the group consisting of a light emitting diode, or a laser; and additional energy amplification comprises an optical amplifier fabricated as a part of the substrate.

7. The apparatus for nanotube growth according to claim 1, wherein the feedatoms are selected from the group of materials that are capable of forming nanotubes consisting of: carbon; silicon; boron and nitrogen; aluminum and nitrogen; or gallium and nitrogen.

8. The apparatus for nanotube growth according to claim 1, wherein the catalyst layer comprises material selected from the group of: iron, nickel, cobalt, copper, gold, silver, platinum, palladium, manganese, chromium, tin, magnesium, aluminum, yttrium, vanadium, molybdenum, rhenium, and alloys of these metals.

9. A broadtip system for nanotube growth comprising: a broadtip substrate assembly of claim 1; a broadtip assembly to which the broadtip substrate assembly is integrated; an articulated arm to which the broadtip assembly is attached; and a motion stage to which the articulated arm is attached.

10. The broadtip system for nanotube growth according to claim 9, wherein catpars replace the catalyst layer.

11. The broadtip system for nanotube growth according to claim 9, wherein the emrad source illuminates the substrate assembly from the front side rather than the backside.

12. The broadtip system for nanotube growth according to claim 9, wherein a feedvoir replaces the feedlayer.

13. The broadtip system for nanotube growth according to claim 9, wherein the emrad source, separate from the substrate, is selected from the group consisting of a laser, a light emitting diode lamp, a fluorescent lamp, or an incandescent lamp.

14. The broadtip system for nanotube growth according to claim 9, wherein the emrad source, fabricated as a part of the substrate, is selected from the group consisting of a light emitting diode, or a laser; and additional energy amplification comprises an optical amplifier fabricated as a part of the substrate.

15. The broadtip system for nanotube growth according to claim 9, wherein the feedatoms are selected from the group of materials that are capable of forming nanotubes consisting of: carbon; silicon; boron and nitrogen; aluminum and nitrogen; or gallium and nitrogen.

16. The broadtip system for nanotube growth according to claim 9, wherein the catalyst layer comprises material selected from the group of: iron, nickel, cobalt, copper, gold, silver, platinum, palladium, manganese, chromium, tin, magnesium, aluminum, yttrium, vanadium, molybdenum, rhenium, and alloys of these metals.

17. A method for nanotube growth comprising the following steps of: 1) preparing a substrate including modifying its surface to have a desired roughness and contouring; 2) laying down a feedlayer onto the substrate; 3) completing a substrate assembly by laying down a thin film of catalyst on the surface of the feedlayer; 4) forming catpars from the thin catalyst film by annealing; 5) installing the assembly in a reaction chamber and sealing the chamber; 6) replacing the atmosphere in the reaction chamber with an ineratmo; 7) adjusting the temperature of the substrate assembly and the pressure of the ineratmo; 8) starting the emrad source to energize feedatoms to migrate to growth sites or catpars; and 9) operating the system for the time interval to achieve the NT growth results.

18. The method of nanotube growth, according to claim 17 wherein step 4 is eliminated.

19. A method for nanotube growth comprising the following steps of: 1) preparing a substrate for a broadtip substrate assembly including proper sizing and modifying its surface to have a desired roughness and contouring; 2) laying down a feedlayer onto the broadtip substrate; 3) completing the broadtip substrate assembly by laying down a thin film of catalyst on the surface of the feedlayer; 4) forming catpars from the thin catalyst film; 5) installing the broadtip substrate into a broadtip assembly; 6) attach the broadtip assembly to an articulated arm; 7) finish a broadtip system construction by attaching the articulated arm to a motion stage; 8) install a target surface upon which a pattern of nanotubes is to be deposited into a reaction chamber; 9) installing the broadtip system into the reaction chamber including connecting electrical leads and sealing the chamber; 10) replacing the atmosphere in the reaction chamber with an ineratmo; 11) adjusting the temperature of the broadtip substrate assembly and the pressure of the ineratmo and 12) initiating an automatic NT growth and motion control system to initiate growth and the motion to deposit a desired pattern on the target substrate.

20. The method of nanotube growth, according to claim 19 wherein step 4 is eliminated.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] FIG. 1 illustrates schematically the embodiment of the present invention in which the NTs grow directly out of the catalyst layer.

[0023] FIG. 2 illustrates schematically the embodiment of the best mode present invention in which the NTs grow directly out of catpars.

[0024] FIG. 3 illustrates schematically the embodiment of the present invention in which the NTs grow directly out of catpars and the feedlayer has been replaced with a feedvoir replenished by a retun.

[0025] FIG. 4 illustrates schematically the basic experimental setup for most of the experiments that have been carried out at the present time.

[0026] FIG. 5 illustrates schematically the broadtip assembly embodiment of the present invention.

[0027] FIG. 6 illustrates schematically a close view of a portion of the broadtip substrate assembly embodiment of the present invention.

[0028] FIG. 7 illustrates schematically the broadtip assembly mounted to the articulated arm and motion stage in operation according to the present invention.

[0029] FIG. 8 illustrates schematically an industrial application embodiment of the present invention wherein a laser delivers energy to substrate assemblies that continuously grow CNTs.

[0030] FIG. 9 illustrates schematically the tratip from the TREKANG patent application.

DETAILED DESCRIPTION OF THE INVENTION

1. Definitions

[0031] BNNT—When used herein shall refer to a boron nitride nanotube.

[0032] Broadtip system—When used herein shall refer to a NT growth system comprising a broadtip assembly mounted to an articulated arm which is itself mounted to a motion stage. This system grows NTs from the broadtip substrate assembly and deposits them onto an adjacent “target surface”. The motion of the broadtip assembly across the adjacent target surface enables patterned three dimensional deposition of NTs. Broadtips are analogous to tratips but are larger with many catalyst particles. Because of their size emrad is used to deliver the energy to the feedlayer instead of plasmons. See FIGS. 5, 6 and 7.

[0033] Broadtip assembly—When used herein shall refer to a subsystem comprising a broadtip substrate assembly mated to an emrad source and packaged to be mounted to an articulated arm for use in a broadtip system. See FIGS. 5 and 7.

[0034] Broadtip substrate assembly—When used herein shall refer to a substrate assembly subsystem configured to be integrated into a broadtip assembly and used in a broadtip system. See FIGS. 5 and 6.

[0035] Catpar—When used herein shall refer to a volume of catalyst material, wherein the size, shape and elemental constituents are appropriate for growing a nanotube: a catalyst particle. The catalyst may contain one or more elemental constituents.

[0036] CNT—When used herein shall refer to a carbon nanotube.

[0037] Emrad—When used herein shall refer to electromagnetic radiation, however generated and of appropriate wavelength, to stimulate CNT growth within the technique being described.

[0038] Feedatom—When used herein shall refer to an atom or molecule that is a chemical constituent of a nanotube: the atomic feedstock of a nanotube.

[0039] Feedlayer—When used herein shall refer to a layer of nanotube feedstock atoms (feedatoms) that may comprise other constituents such as catalyst material.

[0040] Feedvoir—When used herein shall refer to a reservoir of nanotube feedstock atoms (feedatoms) that may contain other constituents such as catalyst material.

[0041] Growth site—When used herein shall refer to a position on a catalyst layer where a nanotube grows out of the surface. In the case of nanotube growth at a growth site, the catalyst layer has not been annealed so catpars have not formed.

[0042] Highq—When used herein shall refer to nearly defect free: high quality. A highq NT is a nanotube that is nearly pristine, perfect and defect free. As such its tensile strength and electrical properties are maximal.

[0043] Ineratmo—When used herein shall refer to the inert, gaseous atmosphere in a CNT growth chamber: an inert atmosphere. If the sides of the substrate are isolated then it refers to the atmosphere on the nanotube growth side (front side) of the substrate. This “inert” atmosphere generally is made up of inert gasses. However, if partial pressures of other gasses, including ones introduced to react with NTs, catpars and/or free carbon, are introduced into the atmosphere during the growth process, the term interatmo still applies.

[0044] Liberate—When used herein shall refer to the process or process by which a feedatom absorbs emrad and breaks its chemical bonds to other atoms in the feedlayer or feedvoir thereby becoming free to migrate.

[0045] Migrate—When used herein shall refer to the process or processes by which a feedatom travels from a feedlayer or feedvoir to a growth site or catpar after being energized. Migrate is a more general form of trek that encompasses trekking to a growth site as well as a catpar.

[0046] NT—When used herein shall refer to a nanotube.

[0047] Plasmon—When used herein shall refer to a quantum of plasma oscillation. This includes all types of plasmons and polaritons such as exciton-polaritons and surface plasmon polaritons. In the context of the current invention, under the right conditions, electromagnetic energy can be transformed at a surface into plasmons capable of propagating the energy through a medium.

[0048] Retun—When used herein shall refer to a replenishment tunnel or other structure in a substrate or wavide that facilitates the replenishment of feedatoms, catalyst material, and/or other materials for nanotube growth. FIG. 3 illustrates a notional retun.

[0049] Substrate assembly—When used herein shall refer to a subsystem comprising a substrate, a feedlayer deposited onto the front side of the substrate and one of two catalyst configurations, either a catalyst layer or catpars, arranged on the front side of the feedlayer.

[0050] Tratip—When used herein shall refer to a traveling micro or nanoscale platform or tip. A nanotube is grown from a catpar attached to the end of the tratip, a moveable platform. The platform or tip is a part of a cantilever or other support structure that facilitates the movement of the nanoscale nanotube growing system. Thus the nanotube may be grown vertically, horizontally or at an angle to enable structured nanotube growths to be fabricated. A tratip is analogous to the sensing tip of an atomic force microscope which is attached to a cantilever. FIG. 9 illustrates a tratip. Alternatively, the tratip could be stationary and the target surface or volume, upon which the nanotube growth is being deposited, could be mobile.

[0051] Trek—When used herein shall refer to the process or processes by which a feedatom travels from a feedlayer or feedvoir to a catpar after being energized. Trekking is the verb form of trek.

[0052] Wavide—When used herein shall refer to a waveguide through a substrate that transports energy in the form of emrad or plasmons.

[0053] 2. Best Mode of the Invention

[0054] FIG. 2 illustrates the best mode contemplated by the inventor of Free Atom Nanotube Growth according to the present invention. The embodiment in FIG. 2 has an array of catpars arranged on the front side of the carbon feedlayer. The feedlayer has been located on the front side of quartz substrate. Emrad in the form of laser radiation is incident from the front side of the substrate assembly. The laser photons liberate some carbon feedatoms from the feedlayer and some of these free atoms migrate to the catpars. At the catpar some of the carbon atoms are incorporated into the growing CNT.

[0055] 3. The Workings of the Invention

[0056] In a reaction chamber, the system shown in FIG. 1 grows CNTs. Emrad, in the form of laser radiation, incident on the bottom of the substrate propagates through the substrate that is transparent to the emrad. The emrad propagates to the feedlayer. All or most of the emrad energy is absorbed in the feedlayer. This energy liberates some of the carbon feedatoms in the feedlayer to migrate (shown by the arrow) through the very thin iron catalyst layer to the growth site growing a CNT. Ideally, the feedatoms are transported to the growth site with an optimal energy for becoming a part of the CNT growing from the catpar. The atmosphere in the chemical reactor where CNT growth is occurring is an ineratmo.

[0057] The targeting of the feedatoms with the energy required to drive the NT growth process makes possible much lower temperature growth than CVD. The low temperature of the substrate during CNT growth made possible by the present invention decreases or eliminates unwanted, extraneous chemical reactions such as amorphous carbon buildup on the surface of the catpars, thereby increasing the time growth may continue.

[0058] The interatmo environment also decreases or eliminates amorphous carbon build up on the catpars. Additionally, the ineratmo decreases or eliminates damage to growing CNTs from unwanted chemical reaction on their surfaces because the hot carbon gas environment of CVD has been eliminated.

[0059] Ostwald ripening, a thermodynamic process that results in small catpars generally losing catalyst atoms to larger catpars. As Ostwald ripening occurs, more catpars stop growing CNTs because the either become too large or too small to sustain CNT growth. The low temperature synthesis possible with the present invention decreases the rate of Ostwald ripening.

[0060] FIG. 3 illustrates the feedvoir embodiment of the current invention which comprises a feedvoir sitting between the catpar and substrate instead of a feedlayer. The larger the feedvoir, the more feedatoms are available for NT growth. Sizing these feedvoirs or the amount of feedatoms contained in feedvoirs enables the tailoring of the growth of NTs, including tailoring the length of the NTs resulting from a given growth run.

[0061] One of the feedvoirs in FIG. 3 illustrates a retun through the substrate for replenishing the feedatoms, catalyst material and/or other materials for NT growth. This represents a variation of the feedvoir embodiment wherein retuns facilitate the replenishment of feedatoms, catalyst material and/or other materials for NT growth from another reservoir. This reservoir would most probably be off the substrate on which the NTs are growing. In this way, continuous NT growth may be accomplished, especially in the case of industrial-scale growth in a manufacturing environment.

[0062] Both feedlayers and feedvoirs are not limited to containing only feedatoms. Catalyst or other materials that are found to be beneficial for the growth of NTs can be added to the feedatoms in the feedlayers or feedvoirs. These materials could be layered or otherwise arranged with feedatoms in the feedlayers or feedvoirs to be liberated at different stages of the growth process.

[0063] FIG. 9 illustrates the tratip embodiment of the TREKANG patent application comprising a catpar residing on a tratip. In this case the tratip can grow the NT while on the move, enabling growth of an NT in three dimensions. Such capability enables NTs to be deposited on an adjacent target surface in patterns. The next embodiment of the present invention is analogous to the tratip.

[0064] Another embodiment of the current invention is the broadtip system shown in FIGS. 5, 6 and 7. The broadtip system comprises the broadtip assembly; broadtip substrate assembly; the articulating arm; and the motion stage that together facilitate the three dimensional motion. In direct analogy of the tratip of the TREKANG application, the broadtip system is a large tratip. The scale of the broadtip substrate assembly is tens to thousands of growth sites or catpars instead of one catpar in the case of a tratip. The broadtip substrate assembly is so large plasmons are not required to couple energy to its feedlayer or feedvoir. Like the tratip, the broadtip assembly is mounted onto an articulated arm and motion stage that facilitates three dimensional motion across an adjacent target surface upon which the broadtip system deposits nanotubes that are growing from the broadtip substrate assembly. The emrad energizing nanotube growth from a broadtip substrate assembly may propagate from the back side of the broadtip substrate assembly, may be incorporated into the broadtip substrate assembly, or propagate from the front side through a transparent adjacent target surface onto the broadtip substrate assembly. Indeed, the three dimensional growth pattern may be controlled by manipulating the emrad intensity, emrad pattern on the broadtip substrate assembly and by turning the emrad source on and off

[0065] 4. How to Make the Invention

Substrate Assembly Considerations

[0066] The substrate assembly is made by coating on the front side a thick feedlayer (˜150 nm) of feedatoms and a thin layer (˜3 nm) of catalyst. Other coating technologies can be used as well. General substrate requirements include 1) the ability to be used in the coating technology processes, 2) the ability to be coated by the various types of feedatoms and catalysts, 3) being relatively impervious to the dissolution of the feedatom and catalyst into the substrate, and 4) the ability to withstand any temperature experienced during a possible annealing step and during the growth of NTs. If the emrad will be incident onto the substrate from the back side then the substrate must be transparent to the emrad.

[0067] Although the substrate used for the experiments was flat and smooth, the substrate may be contoured to concentrate the catalyst and position the catpar. Even in the case of no annealing to form catpars, a roughened or contoured substrate would create more growth sites in the form of irregularities in the otherwise smooth catalyst layer. The substrate assembly properties can be used to tune the amount of energy delivered to the feedlayer or feedvoir. These properties include the substrate contour, thickness and material properties such as transparency.

[0068] Other nanotubes such as silicon (SI), boron nitride (BN), aluminum nitride (AIN) and gallium nitride (GN) can be grown by the current invention. The feedlayer composition would need to be modified to provide the proper feedatoms. The emrad wavelength range would be required to energize the feedatoms to migrate. Two emrad sources of differing wavelength ranges can be used to energize two species of feedatoms.

[0069] It is expected that this nanotube growth technology will work with all metal catalysts such as of iron, nickel, cobalt, copper, gold, silver, platinum, palladium, manganese, chromium, tin, magnesium, aluminum, yttrium, vanadium, molybdenum, rhenium, and alloys of these metals.

Emrad Coniderations

[0070] The emrad may be generated by laser, LED, fluorescent lamp or incandescent lamp. Generally, emrad sources would be external to the substrate. However, in the case of an LED or nanolaser these sources could be fabricated as a part of the substrate. Also, an optical amplifier may be fabricated separately or as part of the substrate to amplify an emrad source.

[0071] Requirements for the emrad source include possessing a wavelength or wavelength range absorbed by the feedlayer, and, once absorbed, imparting enough energy to the absorbing feedatoms to free them to migrate. These free atoms would then form NTs at the growth site or catpar. The wavelength of this emrad should be as short as possible and still fit other criteria such as the required laser power, cost and safety of carrying out the experiment. A laser of 405 nm wavelength and a 365 nm LED lamp were chosen for the experiments.

[0072] A feature of the present invention is that NT growth may be paused or ceased by stopping the emrad. This could allow the fine tuning of NT length or a way to accurately begin and end different stages of NT growth in a multi-stage growth scenario.

Ineratmo Considerations

[0073] The ineratmo mitigates extraneous reactions from atmospheric gasses. Because in the present invention the feedatoms for NT growth do not come from the atmospheric gasses; the constituent gasses, pressure and temperature of the atmosphere can be adjusted to optimize NT growth. The ineratmo gasses may be circulated, filtered, exchanged, monitored and/or changed to facilitate control of the ineratmo constituents, temperature and pressure, thereby maintaining an optimal atmosphere in the reaction chamber. Finally, the ineratmo can be altered during growth process as required to continue growth, change NT characteristics, and functionalize NTs.

Miscellaneous Considerations

[0074] Real time diagnostic measurements may be employed to measure and control the growth and functionalization of NTs. These diagnostics include the NT growth rate and structure; catalyst temperatures, pressures and compositions; feedatom transport; and ineratmo compositions, temperatures and pressures.

[0075] Free Atom Nanotube Growth technology may be adapted to grow assemblages of atoms thereby forming molecules, structures, shapes and machines in an accurate and controlled manner. These assemblages formation processes may or may not require a catalyst to facilitate the formation of the assemblage.

[0076] 5. Experimental Examples

[0077] Proof-of-principle experiments based upon the principles claimed in the Trekking Atom Nanotube Growth (TREKANG) patent application have been performed and are continuing. The results of the experiments are the basis of this patent application, the Free Atom Nanotube Growth (FANG) application.

[0078] A set of basic, proof-of-principle experiment were devised and executed. The major simplification over the TREKANG concept is that there are no wavides. Wavides were conceived to deliver the energy that stimulates growth to the feedlayer in the vicinity of the catpar. The current experiments prove that wavides are not necessary. Further experiments to determine the parameter space over which nanotubes can be grown are continuing.

[0079] FIG. 1 is a schematic illustration of the experimental configuration for most experiments. A two-inch diameter, 6 mm thick quartz disc was used as the substrate. A 140 nm layer of carbon was sputtered onto the front surface of the substrate to form a feedlayer with carbon feedatoms. The sputtered carbon forms an amorphous carbon layer. On the front side of the of the carbon feedlayer a 2-3 nm layer of iron was sputtered. The iron is a catalyst for carbon nanotube growth. The iron layer completes the substrate assembly that consists of the substrate and its carbon and iron layers. The emrad that enters from the bottom of the picture and traverses the quartz substrate is mostly absorbed in the carbon layer. In most experiments the emrad source was a 405 nm, near-uv laser. Other experiments used a 365 nm UV LED lamp. The atmosphere in the chemical reactor chamber, the ineratmo, was composed of argon gas. FIG. 1 also illustrates an unexpected property: carbon nanotubes grew without catpar formation. To the limit of resolution, scanning electron microscope images show the carbon nanotubes growing out of the surface of the iron layer.

[0080] FIG. 2 is a schematic illustration of another experimental configuration which is the best mode of the present invention as conceived by the inventor. One difference in FIG. 2 from FIG. 1 is that the catalyst layer has been annealed to form catpars. The second difference is that the emrad, laser radiation in most experiments, is incident from the front side of the substrate assembly. Carbon nanotubes have been grown from catpars in some of the experiments. Most experiments have been carried out with the radiation incident from the front side of the substrate assembly because the insertion and extraction of the assembly is simpler when the front side is toward the emrad source. However experiments have shown NT growth from emrad illuminating either side of the quartz substrate.

[0081] FIG. 4 illustrates schematically the basic experimental configuration. The substrate can be mounted on the substrate mount with either the front side or back side facing the laser or lamp. Not shown in FIG. 4 are the heaters and thermocouples that are attached to the substrate mount.

[0082] The optimum temperature, pressure, radiation irradiance, radiation wavelength, carbon layer thickness and iron layer thickness have not been determined. Carbon nanotubes were grown with the substrate at ambient temperature and 200 C; argon gas pressures ranging from 50 to 200 Torr; irradiances of a few to tens of milliWatts per square centimeter; and wavelengths of 405 and 365 nm radiation. Experiments are continuing to map out the NT growth parameter space.

[0083] 6. How to Use the Invention

[0084] In the research laboratory, the Free Atom Nanotube Growth technology will enable researchers to grow large amounts of long, highq NTs thereby stimulating research into the properties of the NTs and the macroscopic assemblages formed using these materials. In the case of CNTs these properties include very high tensile strength, high thermal conductivity, for some chiralities low conductivity and the ability to sustain very high electrical current densities, and for other chiralities semiconductor properties. In the case of BNNTs, interesting properties include high tensile strength, high thermal conductivity, low electrical conductivity and neutron absorption based upon the presence of boron. Indeed, the long, highq NTs may reveal properties and applications that are not possible with the currently available NTs. Moreover, the long, highq nanotubes can be used to construct: 1) enhanced strength structures; 2) enhanced conductivity conductors, wires, microscale and nanoscale integrated circuits, microscale and nanoscale transistors, diodes, gates, switches, resistors, capacitors, single sensors and arrays; 3) receivers, rectennas or electromagnetic radiation emitting structures; 4) surface geometries to promote or prevent biological growth; 5) surfaces with special optical, reflective, interference or diffractive properties; 6) surfaces to promote or prevent chemical reactions; 7) structures with certain material properties including strength, hardness, flexibility, density, porosity, etc.; and 8) surfaces that emit particles such as electrons under electrical stimulation (field emission).

[0085] The method for FANG nanotube growth would comprise the steps of: 1) preparing a substrate including modifying its surface to have a desired roughness and contouring; 2) laying down a feedlayer onto the substrate; 3) completing a substrate assembly by laying down a thin film of catalyst on the surface of the feedlayer; 4) forming catpars from the thin catalyst film by annealing; 5) installing the assembly in a reaction chamber and sealing the chamber; 6) replacing the atmosphere in the reaction chamber with an ineratmo; 7) adjusting the temperature of the substrate assembly and the pressure of the ineratmo; 8) starting the emrad source to energize feedatoms to migrate to growth sites or catpars; and 9) operating the system for the time interval to achieve the desired NT growth results.

[0086] In terms of a FANG broadtip system nanotube growth would comprise the steps of: 1) preparing a substrate for a broadtip substrate assembly including proper sizing and modifying its surface to have a desired roughness and contouring; 2) laying down a feedlayer onto the broadtip substrate; 3) completing the broadtip substrate assembly by laying down a thin film of catalyst on the surface of the feedlayer; 4) forming catpars from the thin catalyst film; 5) installing the broadtip substrate into a broadtip assembly; 6) attach the broadtip assembly to an articulated arm; 7) finish a broadtip system construction by attaching the articulated arm to a motion stage; 8) install a target surface upon which a pattern of nanotubes is to be deposited into a reaction chamber; 9) installing the broadtip system into the reaction chamber including connecting electrical leads and sealing the chamber; 10) replacing the atmosphere in the reaction chamber with an ineratmo; 11) adjusting the temperature of the broadtip substrate assembly and the pressure of the ineratmo and 12) initiating an automatic NT growth and motion control system to initiate growth and the motion to deposit a desired pattern on the target surface.

[0087] If the researcher doesn't want to use catpars to grow NTs then step 4 can be eliminated in both of the preceding procedures.

[0088] The inventor envisions transforming the present invention into an industrial process in which a vast amounts of long, highq NTs are created. FIG. 8 illustrates schematically this vision. FIG. 8 shows the side view inside a reaction chamber. Five assemblies each consisting of a substrate with catpars arranged on it sitting above a laser. In between is a lens that transports the photons from the laser to the backside of the substrate. Above the front surface of the five substrates is a “draw bar harvester”. When the NT growth has progressed for a time, the bar moves down, attaches to the growing NT surface and then rises in cadence with the growth. When the NTs are ready to be harvested, an industrial laser cuts the NTs off, above the substrate assembly level. The bar then transports the harvested NTs out of the reaction chamber to a processing location. Another bar moves in and acquires the tops of the growing NTs and the process continues.

[0089] FIG. 7 is an overhead view of another embodiment of an industrial process for the Free Atom Nanotube Growth Technology, in this case a broadtip system. The broadtip assembly, to which the articulated arm attaches, which in turn is attached to a motion stage moves the broadtip assembly in three dimensions. Additionally, to efficiently deposit vertical NTs, the broadtip assembly also rotates in two axes. Two raised platforms and a sloped surface on the drawing facilitate the vertical NT and NT bridge structure features. The varied forms of the patterns of NTs deposited on the surface illustrate the potential capabilities of this system as envisioned by the inventor.

[0090] Achieving industrial-scale manufacturing of long, highq NTs means that these materials will become increasingly plentiful and inexpensive. In the case of CNTs, with their remarkable tensile strength and electrical properties, new ways of building existing commodities will be developed and new products will be invented using the superior material properties. CNT high strength material, possibly exceeding in tensile strength all existing materials by an order of magnitude or more, will revolutionize life on Earth. Additionally, with patterned growth technology, CNT electrical components created at the nanometer scale lengths will enable smaller, lower power integrated circuits and will transform human society. The most extreme example of the benefits may be that high strength CNTs will enable the Space Elevator, thereby opening the resources of space to mankind in the form of enhanced Earth observation, space-based solar power, asteroid mining, planetary defense and colonization of the moons and planets of our solar system!

[0091] It will be appreciated by those skilled in the art that the present invention is not restricted to the particular preferred embodiments described with reference to the drawings, and that variations may be made therein without departing from the scope of the present invention as defined in the appended claims and equivalents thereof.