TWI320026B - Field emission componet and method for making same - Google Patents

Field emission componet and method for making same Download PDF

Info

Publication number
TWI320026B
TWI320026B TW95123835A TW95123835A TWI320026B TW I320026 B TWI320026 B TW I320026B TW 95123835 A TW95123835 A TW 95123835A TW 95123835 A TW95123835 A TW 95123835A TW I320026 B TWI320026 B TW I320026B
Authority
TW
Taiwan
Prior art keywords
field emission
carbon nanotube
wire
emission element
carbon
Prior art date
Application number
TW95123835A
Other languages
Chinese (zh)
Other versions
TW200800798A (en
Inventor
Liang Liu
Kai-Li Jiang
Shou-Shan Fan
Ceasar Chen
Hsi Fu Lee
Ga-Lane Chen
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed filed Critical
Priority to TW95123835A priority Critical patent/TWI320026B/en
Publication of TW200800798A publication Critical patent/TW200800798A/en
Application granted granted Critical
Publication of TWI320026B publication Critical patent/TWI320026B/en

Links

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a field emission element and a method of fabricating the same, and more particularly to a nanocarbon tube field emission element and a method of fabricating the same. [Prior Art] Carbon Nanotube (CNT) is a new type of carbon material discovered by Japanese researchers Πjima in 1991. See also

"Helical Microtubules of Graphitic Carbon", S. Iijima,

Nature, vol. 354, p56 (1991). The carbon nanotubes have excellent electrical conductivity, good chemical stability and large aspect ratio, and they have a tip surface area close to the theoretical limit (the smaller the tip surface area, the local electric = the more concentrated) The carbon nanotubes have potential application prospects in the field of field emission. Current research indicates that one of the best field emission materials known for the carbon nanotube system, (iv) tip-to-scale tapping, Chennai to tens of nanometers, has a very low field emission voltage (less than the volts). It transmits extremely large current density, and its current is extremely stable and has a long service life. Therefore, it is very suitable as an excellent field emission element for use in electron emission components of field emission equipment. A conventional carbon nanotube field emission element generally includes at least a conductive cathode 2 and a carbon nanotube as a emitting end, and the nanocarbon (4) is formed on the conductive electrode. At present, the preparation methods of the Nei tube field Wei components are mainly the method of flexor and growth. Its towel, mechanical methods include screen printing to = compound. The screen printing method is generally printed on the conductive cathode by means of screen printing of the nano carbon mixture. The 132,0026 methods usually require a uniform dispersion of carbon nanotube slurry, which requires drying, rubbing, dust removal, sintering, etc. after printing, and the process is complicated, and the printing method is not suitable for making large current or high precision field emission. element. Viscose method The carbon nanotubes have been manipulated by atomic force microscopy, and the carbon nanotubes are fixed to the conductive cathode with a conductive paste. This method is simple, but complicated and inefficient. Preparation (4) The current carrying capacity of the emitter is generally low. In addition, during the operation of the viscose method, the chemical adhesive layer will penetrate into the tiny nano-anti-g gap, and the surface tension easily changes the carbon nanotube emitter. shape. In addition, since the chemical glue generally cannot withstand the sealing or exhausting temperature required for the electronic vacuum component (generally 3 〇 (rc 〜 5 〇 (rc)), the practical application of the method is limited. In situ growth method The carbon nanotubes are directly grown on the conductive cathode by chemical vapor deposition, arc discharge or radium-burning method. The method is simple to operate, and the carbon nanotubes are Conductive cathode_electric_good, the carbon nanotubes and the conductive cathode have weaker binding ability, so that the carbon nanotubes are detached or pulled out by the electric field force, thereby causing damage to the field emission element. Moreover, it is difficult to control due to financial methods. The number and direction of the growth of the carbon nanotubes, so there are still problems of low efficiency and poor controllability. 3 'In-situ growth method for the selection of the cracked base material, it is necessary to use the crushing and oxygen that does not affect the chemical vapor conditions. Oxygen cutting, high charm metal, etc., or coating the surface of the substrate - a layer of isolation layer. Moreover, the substrate material also needs to be able to shoot high temperature carbon nanotubes, so the cost is high, which is not suitable for practical applications. It is necessary to provide a field emission element which is easy to be fixed to a conductive cathode, and has an electrical connection 8 1320026 which is good in current carrying capacity, simple in production and operation, and easy to be practically applied, and a preparation method thereof. The embodiment describes a field emission element and a preparation method thereof, which have the characteristics of being easily fixed to a conductive cathode, having good electrical connection, being easy to produce and operate, and being easy to be practically applied. A field emission element including at least one carbon nanotube field The emission wire and the at least one support wire 'the carbon nanotube field emission wire and the support wire are intertwined to form a stranded structure. The carbon nanotube field emission wire is a nano carbon line or a linear nano carbon Tube polymer composite material The carbon nanotube field emission wire has a diameter of 2 to 200 microns. The carbon nanotube polymer composite material comprises a polymer material and a carbon nanotube uniformly dispersed in the polymer material. The carbon nanotubes have a diameter of 5 to 40 nm. The mass percentage of the carbon nanotubes in the carbon nanotube polymer composite is 1 to 1%. The support material is copper, silver, gold, nickel or molybdenum. The polymer material is polyethylene terephthalate, polycarbonate, acrylonitrile-butadiene propylene-styrene copolymer or polycarbonate. a method for preparing a field emission element, comprising the steps of: providing at least one carbon nanotube field emission wire and at least one support wire; using a spinning process The carbon nanotube field emission wire and the support body 9 13200.26 wire are intertwined to form a stranded structure; the stranded wire formed by winding the carbon nanotube field emission wire and the support wire are cut according to a predetermined length, The field emission element is formed. The cutting method includes mechanical shearing or laser cutting. Compared with the prior art, the field emission element comprising the support wire and the nano rabbit official field emission wire has the advantages that: first, using nanometer The carbon tube field emission wire is used as an emitter to emit electrons. The excellent electron emission performance of the carbon nanotube itself is used. Secondly, the support wire and the carbon nanotube field emission wire are formed. The stranded wire structure has a macroscopic size, and the support wire is used for fixing and protecting the carbon nanotube field emission wire, so that the field emission component has good mechanical properties, is easy to be fixed on the cathode electrode, is easy to operate, can be mass-produced and is conveniently applied. The device is emitted in various vacuum fields. [Embodiment] Hereinafter, the present invention will be further described in detail with reference to the accompanying drawings. Referring to FIG. 1 and FIG. 2, a first embodiment of the present invention provides a field emission element 10'. The field emission element 10 includes a nano-tube field emission wire 12 and is spirally wound around the nano-disc field. At least one support wire 14 of the wire 12. The carbon nanotube field emission wire 12 is for emitting electrons, and the support wire 14 provides mechanical support and protection to the carbon nanotube field emission wire 12. The field emission device 10 of the present embodiment preferably uses a multi-strand strand structure formed by a carbon nanotube field emission wire 12 and a plurality of support wires 14, which are located at the center of the field emission element 1 The plurality of branches 10 13200.26 of the target wire 14 are wound around the periphery of the carbon nanotube field emission wire 12. The support wire 14 can be selected from copper, silver, gold, nickel, or other metallic materials. The shape of the support wire 14 is linear, and its diameter can be selected according to actual needs, and this embodiment is preferably several tens of micrometers to several millimeters. The carbon nanotube field emission wire 12 is a nano carbon line drawn from a super-sequential carbon nanotube array, which contains a large number of carbon nanotubes. According to actual needs, the nano carbon tube field emission wire 12 can also be a combination of a plurality of nano carbon lines drawn from the super-sequential carbon nanotube array, and the diameter range of the nano carbon tube field emission wire 12 is preferably 2 to 200 microns. In addition, the carbon nanotube field emission wire 12 in this embodiment can also be replaced by a linear carbon nanotube polymer composite. The linear carbon nanotube polymer composite comprises a polymeric material and a carbon nanotube uniformly dispersed in the polymeric material. The polymer material of this embodiment may be selected from the group consisting of Polyethylene Terephtha late (PET), polycarbonate (PC), acrylonitrile-butadiene-diene-vinyl copolymerization. Polymer materials such as Acrylonitrile-Butadiene Styrene Terpolymer (ABS), polycarbonate/acrylic acid, and styrene-diphenylene oxide (PC/ABS). Among them, the mass percentage of the carbon nanotubes in the composite material is preferably 1% in the present embodiment. When the field emission device 10 of the present embodiment is applied, the single or multiple field emission elements 10 may be disposed on the cathode electrode through their support body lines to form a single field emission electron source or a planar array arrangement. The field emits an electron source and electrically connects the carbon nanotube field emission wire 12 to the cathode electrode, directly applies a voltage through the cathode electrode - the carbon nanotube field emission wire 12, or applies a voltage to the nanowire through the support wire 14 The carbon tube field emission wire 12 emits electrons using the excellent electron field emission properties of the carbon nanotube material itself. Referring to FIG. 3, a method for fabricating a field emission device 10 according to a first embodiment of the present invention includes the following steps: • First, a linear carbon nanotube field emission wire 12 is provided, and the linear carbon nanotube field emission wire 12 is selectable. It is a nano carbon line or a linear nano tube polymer composite. The method for preparing the nanocarbon pipeline of the present embodiment comprises the steps of: providing an array of carbon nanotubes, clamping a bundle of carbon nanotubes with a pair of tweezers, and applying external force to draw. Due to the effect of van der Waals force, the ends of the carbon nanotube bundles are connected end to end, forming a carbon nanotube line along the drawing direction. * The above-mentioned carbon nanotube array capable of drawing a nano carbon line needs to meet the following three conditions: the surface of the substrate is smooth and smooth; the growth rate is high; and the partial pressure of the reaction precursor is low. In addition, the diameter of the nanocarbon line can be controlled by the tip size of the drawing tool, and the smaller the tip size, the smaller the diameter of the obtained carbon carbon line. The length of the carbon nanotube wire is determined by the area of the carbon nanotube array. Typically, a square carbon nanotube array of 1 square centimeter (cm2) can draw a nanocarbon line with a length of 10 meters (m). The force of pulling the nano carbon line is 12 1320026. The diameter of the mosquito from the diameter of the rear line of the nanometer is larger. The larger the diameter, the larger the diameter of the nano carbon official line is preferably 2 to micron. The method for preparing the linear carbon nanotube polymer composite comprises the following steps: providing a uniformly dispersed prepolymer solution or a prepolymer monomer solution; adding the carbon nanotube to the solution And dispersing the same sentence; the prepolymer solution is polymerized to form a polymer, and extruded into an extrusion device to form a linear carbon nanotube polymer composite. The preparation method of the carbon nanotubes can adopt the chemical vapor deposition method, the arc discharge method, the laser burnt method, etc. in the prior art. In this embodiment, the chemical vapor deposition method is used, and the diameter of the carbon nanotubes used is in the range of 5~ 4 〇 nano. The polymer material of this embodiment may be selected from the group consisting of polyethylene terephthalate (PET), polycarbonate (PC), acrylonitrile-butadiene propylene-styrene copolymer ( Acrylonitrile-Butadiene Styr'ene Terpolymer (ABS), polycarbonate/acrylonitrile-butadiene-styrene copolymer (PC/ABS) and other polymer materials. The carbon nanotube polymer composite material obtained in this embodiment is a composite fiber having a diameter of 2 to 200 micrometers, wherein the mass percentage of the carbon nanotubes in the composite material is preferably 2 in this embodiment. °/〇. Next, a plurality of linear support wires 14 having substantially the same length and diameter are provided. The material of the support wire 14 can be selected from copper, silver, gold, magnet, 13 1320026 molybdenum or other metal materials. The support body wire 14 is linear in shape, and its diameter and length can be selected according to actual needs. The diameter of the branch wire 14 of the present embodiment is preferably several tens of micrometers to several millimeters. Finally, a plurality of linear support wires 14 are wound around the carbon nanotube field emission wires 12 to form the field emission elements 10. The linear support wire 14 provides mechanical support and protection to the carbon nanotube field emission wire 12. In this embodiment, the carbon nanotube field emission wire 12 and the plurality of support wires 14 can be twisted together by a spinning process to form a plurality of strands. "The length of the required field emission component can be directly formed according to actual needs, or For the convenience of production, long lines can be made first, and then cut into short lengths of field emission elements by mechanical shearing or laser cutting. Referring to Figure 4, a second embodiment of the present invention provides a field emission element 20' which includes at least one carbon nanotube field emission wire 22 and a plurality of support wires 24. The structure of the field emission element 20 of the second embodiment is substantially the same as that of the field emission element 1 of the first embodiment of the present invention. The difference is that the field emission element 20 of the second embodiment uses one or more carbon nanotubes. The field emission wire 22 replaces the peripheral support wire 14 in the field emission element 10 of the first embodiment, and a stranded wire structure formed by a support wire 24 at the center of the field emission element 20. In the second embodiment of the present invention, the structure and material of the carbon nanotube field emission wire 22 and the branch body wire 24 are the same as those of the first embodiment, and the preparation method of the field emission element 20 is also the field emission of the first embodiment. Element 14 1320026 Item 10 is substantially identical 'only one or more carbon nanotube field emission wires 22 are used to replace the surrounding support wires 24 to form a multi-strand structure. The invention comprises a field emission element of a support wire and a carbon nanotube field emission wire, which has the advantages that: firstly, the use of a carbon nanotube field emission wire as an emitter emits electrons, and the excellent electron emission performance of the carbon nanotube itself can be utilized. Secondly, the multi-strand strand structure formed by the support wire and the carbon nanotube field emission wire has a macroscopic size, and the nano-carbon tube field emission wire is fixed and protected by the branch body wire, so that the field emission component has good mechanical structure. Performance, easy to operate, mass-produced and easily applied to a variety of vacuum field emission devices. In summary, the present invention has indeed met the requirements of the invention patent, and has filed a patent application according to law. However, the above is only a preferred embodiment of the present invention, and it is not possible to limit the scope of the patent application in this case. Any modification or change made by a person who is eager to learn the skill of the present invention in accordance with the spirit of the present invention shall be within the scope of the following patent application. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a perspective view showing a field emission element of a first embodiment of the present invention. Figure 2 is a schematic cross-sectional view along line Π~Ι I of Figure 1. Fig. 3 is a flow chart showing the method of preparing the field emission element of the first embodiment of the present invention. Fig. 4 is a plan view showing a field emission element of a second embodiment of the present invention. 1320026 [Description of main component symbols] Field emission element 10 Nano carbon tube field emission wire 12 Support wire 14 Field emission element 20 Nano carbon tube field emission wire 22 Support wire 24

16

Claims (1)

13200.26 . X. Patent Application Scope 1. A field emission element is improved in that the field emission element package includes at least one carbon nanotube field emission wire and at least one support wire material, and the carbon nanotube field emission The wire and the support wire are intertwined to form a multi-strand structure. 2. The field emission element of claim 1, wherein the carbon nanotube field emission wire is a nano carbon line or a linear carbon nanotube polymer composite. 3. The field emission element of claim 2, wherein the carbon nanotube field emission wire has a diameter of 2 to 200 microns. 4. The field emission element of claim 2, wherein the carbon nanotube polymer composite comprises a polymer material and a carbon nanotube uniformly dispersed in the polymer material. 5. The field emission element of claim 4, wherein the carbon nanotube has a diameter of 5 to 40 nm. 6. The field emission element according to claim 4, wherein the carbon nanotube polymer composite material has a mass percentage of the carbon nanotubes of 1% to 10%. 7. The field emission element of claim 1, wherein the support material is copper, silver, gold, nickel or molybdenum. 8. The field emission element according to claim 4, wherein the polymer material is polyethylene terephthalate, polycarbonate, acrylonitrile butadiene propylene-styrene copolymer Or polycarbonate / propylene guess a small dilute and a stupid B-baked copolymer. 17 13200-26 * 9. A method for preparing a field emission element, comprising the steps of: providing at least one carbon nanotube field emission wire and at least one support wire; and transmitting the carbon nanotube field by a spinning process The wire and the support wire are intertwined to form a stranded structure; the strands of the carbon nanotube field emission wire and the support wire are intertwined according to a predetermined length to form a field emission element. The method of producing a field emission element according to claim 9, wherein the cutting method comprises mechanical shearing or laser cutting.
18
TW95123835A 2006-06-30 2006-06-30 Field emission componet and method for making same TWI320026B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
TW95123835A TWI320026B (en) 2006-06-30 2006-06-30 Field emission componet and method for making same

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
TW95123835A TWI320026B (en) 2006-06-30 2006-06-30 Field emission componet and method for making same

Publications (2)

Publication Number Publication Date
TW200800798A TW200800798A (en) 2008-01-01
TWI320026B true TWI320026B (en) 2010-02-01

Family

ID=44764929

Family Applications (1)

Application Number Title Priority Date Filing Date
TW95123835A TWI320026B (en) 2006-06-30 2006-06-30 Field emission componet and method for making same

Country Status (1)

Country Link
TW (1) TWI320026B (en)

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TWI383425B (en) * 2008-01-04 2013-01-21 Hon Hai Prec Ind Co Ltd Hot emission electron source and method of making the same
CN101499337B (en) 2008-02-01 2013-01-09 清华大学 Cable production method
CN101499389B (en) 2008-02-01 2011-03-23 鸿富锦精密工业(深圳)有限公司 Electronic emitter
CN101497437B (en) 2008-02-01 2012-11-21 清华大学 Method for preparing carbon nano-tube compound film
TWI380949B (en) * 2008-03-07 2013-01-01 Hon Hai Prec Ind Co Ltd Carbon nanotube yarn strucutre
CN101527327B (en) 2008-03-07 2012-09-19 清华大学 Solar cell
CN101552295A (en) 2008-04-03 2009-10-07 清华大学;鸿富锦精密工业(深圳)有限公司 Solar cell
CN101556839B (en) 2008-04-09 2011-08-24 清华大学 Cable
CN101562204B (en) 2008-04-18 2011-03-23 鸿富锦精密工业(深圳)有限公司 Solar energy battery
CN103730303B (en) * 2012-10-10 2016-09-07 清华大学 Field emission electron source array and the field emission device

Also Published As

Publication number Publication date
TW200800798A (en) 2008-01-01

Similar Documents

Publication Publication Date Title
Pan et al. Field emission properties of carbon tubule nanocoils
JP5539663B2 (en) coaxial cable
Ball Roll up for the revolution
CA2471603C (en) Iron/carbon composite, carbonaceous material comprising the iron/carbon composite, and process for producing the same
Collins et al. Nanotubes for electronics
US6057637A (en) Field emission electron source
Ajayan et al. Applications of carbon nanotubes
CN1988108B (en) Field emitting cathode and lighting device
Zhang et al. Field emission of electrons from single LaB6 nanowires
US6709566B2 (en) Method for shaping a nanotube and a nanotube shaped thereby
JP3740295B2 (en) Carbon nanotube device, the manufacturing method and the electron-emitting device
ES2386584T3 (en) Flat thermal source
US9095049B2 (en) Method for making an electromagnetic shielding layer
JP2010115778A (en) Manufacturing method of nanowire structure
US20100104808A1 (en) Carbon nanotube composite and method for fabricating the same
EP2586744A1 (en) Nanostructure and precursor formation on conducting substrate
KR20090041765A (en) Carbon nanotubes and method of growing the same, hybrid structure and method of growing the same and light emitting device
Singh et al. Synthesis and characterization of carbon nanofibers produced by the floating catalyst method
JP2009184907A (en) Carbon nanotube composite material
JP2009184910A (en) Linear carbon nanotube structure
US20040020681A1 (en) Power cable
JP4207398B2 (en) Method for manufacturing wiring of carbon nanotube structure, wiring of carbon nanotube structure, and carbon nanotube device using the same
US7586249B2 (en) Field emission device and method for making the same
US6465132B1 (en) Article comprising small diameter nanowires and method for making the same
CN101471211B (en) Thermal emission electronic component