200800798 九、發明說明： 【發明所屬之技術領域】 . 树明係涉及-種場發射元件及其製備方法，尤其涉 及一種奈米碳管場發射元件及其製備方法。 【先前技術】 奈米碳管（Carbon —tube，CNT)係-種新型石炭材 料’由日本研究人員Η細在1991年發現，請參見 φ "Helical Microtubules of Graphitic Carbon", S. Iijima,200800798 IX. Description of the invention: [Technical field to which the invention pertains] The tree structure relates to a field emission element and a preparation method thereof, and more particularly to a nano carbon tube field emission element and a preparation method thereof. [Prior Art] A carbon nanotube (Carbon-tube, CNT) system - a new type of carbonaceous material was discovered by a Japanese researcher in 1991, see φ "Helical Microtubules of Graphitic Carbon", S. Iijima,
Nature，vol· 354, P56 (1991)。奈米碳管具有極優異的導’ 電性能、良好的化學穩定性和較大的長徑比，且其具有幾 乎接近理論極關纽表面積（尖端表面積愈小，其局部電 場愈集中）’故奈米碳管在場發射領域具有潛在的應用前 ϋ前的研究表明，奈米碳管係已知的最好的場發射材 料之一，它的尖端尺寸只有幾奈米至幾十奈米，具有極低 的場發射電壓（小於100伏），可傳輪極大的電流密度，並 • 且電流極穩定，使用壽命長，因此非常適合作爲-種極佳 的場發射元件’應麟場發侧示料設備的電子發射部 件中。 傳統的奈米碳管場發射元件一般至少包括一導電陰極 電極和作爲發射端的奈米碳管，該奈米碳管形成於該^電 陰極電極上。目前，奈米碳管場發射元件的製備方法主要 包括機械方法和原位生長法。其中，機械方法包括絲網印 刷法和膠粘法。絲網印刷法一般通過將奈米碳管粉末混合 到漿料裏，再通過絲網印刷的方式印刷到導電陰極上。此 200800798 去通$舄要配置分散均勻的奈来碳管漿料，在印刷後 為要火、乾摩擦、除粉塵、燒結等步驟，工藝複雜，且印 刷法不適於製作大電流或高精度的場發射元件。枯膠法係 通過原子力顯微鏡操縱已經合成的奈米碳管，將奈米碳管 用導電膠固定到導電陰極上，雜方絲式簡單，但操作 繁雜且效率低。製備出的發射體電流承載能力一般較低， 另，在粘膠法的操作過程中，化學膠層會滲透到微小的奈 米碳管間隙巾，其表面張力容易改變奈米碳管發射體的形 狀。另，由於化學膠一般情況下無法承受電子真空部件所 需的封接或排氣溫度（一般爲30{rc〜50(rc)，故，該方法 的實際應用受到限制。 原位生長法係先於導電陰極上鍍上金屬催化劑，然後 通過化學氣相沈積、電弧放電或鐳射燒蝕法等方法在導電 陰極上直接生長出奈米碳管，此種方法操作簡單，奈米碳 官與導電陰極的電接觸良好。惟，奈米碳管與導電陰極的 結合能力較弱，於使用時奈米碳管易脫落或被電場力拔 出，從而導致場發射元件損壞。且，由於該方法不易控制 奈米碳管的生長數量和方向，故仍存在效率低且可控性差 的問題。另，原位生長法對陰極基底材料有所選擇，需要 採用不影響化學氣相條件的；5夕、氧化铭、氧化石夕、高溶點 金屬等，或者基底表面塗敷一層隔離層。且，基底材料還 需要能夠耐受奈米碳管生長的高溫範圍，因此該方法成本 較高，不利於實際應用。 有雲於此，供一種容易固定於導電陰極、電性連接 8 200800798 良好、電流承载能力南且生産和操作簡易、易於實際應用 的場發射元件及其製備方法實為必要。 【發明内容】 以下，將以若干實施例說明一種場發射元件及其 製備方法，其具有容易固定於導電陰極、電性連接良 好、易於生產和操作、易於實際應用的特點。 一種場發射元件’其包括至少-奈米碳管場發射 線材及至少-支㈣線材，該奈米碳管場發射線 該支撐麟#相魏卿❹酸線結構。 和 該奈米碳管場發射線材為奈米碳管線 碳管聚合物複合材料。 炚奈米 該奈来袄官場發射線材的直徑爲2〜200微米。 該奈米乂官聚合物複合材料包括聚合物材 勻分散於料合物㈣巾的奈米碳管。 °均 該奈米琰管直徑爲5〜40奈米。 八1=1 f聚合物複合㈣中奈米碳管的 分比含篁爲1〜1Q%。 意百 該支撐發特料為銅、銀、金、錄或姻。 該水口物柯料為聚對笨二甲酸乙二醇醋、聚0 酯、丙烯腈〜丁-松 爽峻 ㈣腈，烯共聚物或聚、 提供至少；射二:二製備方法，其包括以下步騍: 姑.闲坊綠、 發射線材與至少一支撐體線 、、x藝將該奈米碳管場發射線材與該支撐體 9 200800798 線材相互纏繞形成多股絞線結構；按照預定長声切判 該奈米碳管場發射線材與該支撐體線材相互纏銬^ 成的多股絞線，形成場發射元件。 該切割方法包括機械剪切或鐳射切割。 相較于先前技術，所述的包含支撐體線材和奈米 碳管場發射線材的場發射元件，其優點在於：首先， 使用奈米碳管場發射線材作爲發射體發射電子可利 用奈米碳管本身優良的電子發射性能；其次，支撐體 線材與奈米碳管場發射線材形成的多股絞線結構具 有宏觀尺寸，利用支撐體線材對奈米碳管場發射線材 固疋和保護作用’使場發射元件具有良好的機械性 月色’易於固定於陰極電極’容易操作，能夠大量生産 並且方便地應用於各種真空場發射器件。 【實施方式】 下面將結合附圖對本發明作進一步的詳細說明。 請參閱圖1和圖2 ’本發明第一實施例提供一種場 發射元件10，該場發射元件10包括一奈米碳管場發 射線材12及以螺旋狀纏繞於該奈米碳管場發射線材 12的至少一支撐體線材14。該奈米碳管場發射線材 12用於發射電子’該支樓體線材14對該奈米碳管场 發射線材12提供機械支撐和保護作用。本實施例場 發射元件10優選採用一根奈米碳管場發射線材12與 多根支撐體線材14形成的多股絞線結構，該奈米破 管場發射線材12位於場發射元件10中心，該多根支 200800798 撐體線材14纏繞於該奈米破管場發射線材12的週 邊。 e 該支撐體線材14可選用銅、銀、金、鎳、鉬或其 ^ 他金屬材料。該支撐體線材14形狀爲線狀，其直徑 可根據實際需要而選定，本實施例優選爲幾十微米至 幾毫米。 該奈米碳管場發射線材12係由超順排奈米碳管陣 列拉出的奈米碳管線，其包含有大量奈米碳管。根據 ⑩ 實際需要’該奈米碳管場發射線材12也可以由超順 排奈米碳管陣列拉出的多根奈米碳管線的組合，該奈 米碳管場發射線材12的直徑範圍優選爲2〜200微米。 另’本實施例中奈米碳管場發射線材12也可用線 狀奈米碳管聚合物複合材料替代。該線狀奈米碳管聚 合物複合材料包括聚合物材料和均勻分散於該聚合 物材料中的奈米碳管。本實施例聚合物材料可選自聚 對苯二曱酸乙二醇酯（Polyethylene Terephthalate， 鲁 PET)、聚碳酸酯（Polycarbonate，PC)、丙烯腈一丁 二烯 丙烯一苯乙烯 共聚物 (Acrylonitrile-Butadiene Styrene Terpolymer, ABS)、聚碳酸酯/丙烯腈一丁二烯一笨乙烯共聚物 (PC/ABS)等高分子材料。其中，奈米碳管在該複合材 料中的質量百分含量爲1%〜10%，本實施例優選爲2%。 本實施例場發射元件在應用時，可視實際需要 將單個或多個場發射元件通過其支撐體線材14固 11 200800798 定於陰極電極上以形成單個場發射電子源或平面陣 列排列的場發射電子源，並使得奈米碳管場發射線材 ' 12與陰極電極電性相連，通過陰極電極直接施加電壓 w 于奈米碳管場發射線材12，或通過支撐體線材14施 加電壓于奈米碳管場發射線材12,利用奈米碳管材料 本身優異的電子場發射性能發射電子。 請參閱圖3，本發明第一實施例場發射元件的 製備方法包括以下步驟： _ 首先，提供-線狀奈米碳管場發射線材12，該線 狀奈米碳管場發射線材12可選擇爲一奈米碳管線或 一線狀奈米碳管聚合物複合材料。 本實施例製備該奈米碳管線的方法包括以下^ 驟：提供一奈米碳管陣列，用一鑷子夾住一束奈米石炭 管，施加外力抽拉。由於凡德瓦力的作用，奈沭破賞 束端部首尾連接在一起，沿抽拉方向形成一奈米破賞 • 線。 上述能抽拉奈米碳管線的奈米碳管陣列，需滿足 以下三個條件：基底表面平整光滑；生長速率高’反 應前體分壓低。 另，奈米碳管線的直徑可由抽拉工具的尖端尺十 控制，尖端尺寸越小，獲得的奈米碳管線的直拉越 小。奈米碳管絲線的長度由奈米;6炭管陣列的面積/、 定，通常1平方釐米（cm2)的奈米碳管陣列彳抽拉出長 度爲10米（m)的奈米碳管線。抽拉奈米碳管線的力的 12 200800798 大小由奈米碳管線的直徑決定，直徑越大，所需的力 越大。本實施例奈米礙管線的直徑範圍優選爲2〜2 0 0 ^ 微米。 ^ 本實施例製備該線狀奈米碳管聚合物複合材料的 方法包括以下步驟：提供一種分散均勻的預聚物溶液 或預聚物單體溶液；將奈米碳管加入該溶液並均勻分 散；將該預聚物溶液聚合形成聚合物，並通過擠出設 備擠壓成型形成線狀奈米碳管聚合物複合材料。 • 奈米碳管的製備方法可採用現有技術中的化學氣 相沈積法、電弧放電法、鐳射燒蝕法等，本實施例採 用化學氣相沈積法，所用的奈米碳管直徑範圍爲5〜40 奈米。 本實施例聚合物材料可選自聚對苯二曱酸乙二醇 酯（Polyethylene Terephthalate，PET)、聚碳酸酯 (Polycarbonate, PC)、丙浠腈一丁二烯丙烯一苯乙 烯共聚物（Acrylonitrile-Butadiene Styfene ® Terpolymer，ABS)、聚碳酸醋/丙烯腈一丁二烯一苯 乙烯共聚物（PC/ABS)等高分子材料。本實施例得到的 奈米碳管聚合物複合材料爲直徑可選擇爲2〜200微米 的複合材料纖雄，其中奈米碳管在該複合材料中的質 量百分含量爲1%〜10%，本實施例優選爲2%。 其次’提供多個長度與直徑基本相同的線狀支撐 體線材14。 該支撐體線材14的材料可選用銅、銀、金、鎳、 13 200800798 鉬或其他金屬材料。該支撐體線材14形狀爲線狀， 其直徑和長度可根據實際需要而選定，本實施例支撐 體線材14的直徑優選爲幾十微米到幾毫米。 最後，將多個線狀支撐體線材14缠繞於該奈米碳 管場發射線材12,形成場發射元件10。該線狀支標 體線材14對該奈米碳管場發射線材12提供機械支撐 和保護作用。 本實施例可通過紡線工藝將奈米碳管場發射線材 12與多根支撐體線材14絞在一起編成多股絞線。< 根據實際需要直揍製成所需場發射元件的長度，威 者，爲製作方便也可先製成長線，再通過機械剪切威 鐳射切割的方法切短成所需長度的場發射元件。 請參閱圖4,本發明第二實施例提供一種場發射元 件20，該場發射元件20包括至少一奈米破管場發射 線材22及多個支撐體線材24。該第二實施例場發射 元件20的結構與本發明第一實施例場發射元件10基 本相同，其區別在於：第二實施例場發射元件20爲 採用一根或多根奈米碳管場發射線材22替代第，實 施例場發射元件10中位於週邊的支撐體線材丨4，及 位於場發射元件20的中心的一根支撐體線材24形成 的多股絞線結構。 本發明第二實施例中奈米碳管場發射線材22及支 撐體線材24的結構和材料均與第一實施例相同，真 場發射元件20的製備方法也與第一實施例場發射元 14 200800798 件10基本相同’只需以一根或多根奈米碳管場發射 線材22替代遇邊的支撐體線材24相互纏繞形成多股 . 絞線結構。 本發明包含支撐體線材和奈米碳管場發射線材的 場發射元件’其優點在於··首先’使用奈米碳管場發 射線材作爲發射體發射電子可利用奈米碳管本身優 良的電子發射性能；其次，支撐體線材與奈米碳管場 發射線材形成的多股絞線結構具有宏觀尺寸，利用支 Φ 撐體線材對奈米碳管場發射線材固定和保護，使場發 射元件具有良好的機械性能，容易操作，能夠大量生 産並且方便地應用於各種真空場發射器件。 綜上所述，本發明確已符合發明專利之要件，遂 依法提出專利申請。惟，以上所述者僅為本發明之較 佳實施例，自不能以此限制本案之申請專利範圍。舉 凡熟悉本案技藝之人士援依本發明之精神所作之等 效修飾或變化，皆應涵蓋於以下申請專利範圍内。 I 【圖式簡單說明】 圖1係本發明第一實施例的場發射元件的立體示 意圖。 圖2係圖1沿ΙΙ-Π線的剖面示意圖。 圖3係本發明第一實施例的場發射元件的製備方 法的流程示意圖。 圖4係本發明第二實施例的場發射元件的俯視示 意圖。 15 200800798 w 【主要元件符號說明】 場發射元件 10 奈米碳管場發射線材 12 支撐體線材 14 場發射元件 20 奈米碳管場發射線材 22 支撐體線材 24Nature, vol. 354, P56 (1991). The carbon nanotubes have excellent electrical conductivity, good chemical stability and large aspect ratio, and they have a surface area close to the theoretical limit (the smaller the tip surface area, the more concentrated the local electric field). Nanocarbon tubes have potential applications in the field of field emission. Previous studies have shown that one of the best field emission materials known for the carbon nanotube system, its tip size is only a few nanometers to tens of nanometers. It has a very low field emission voltage (less than 100 volts), can transmit a very large current density, and has extremely stable current and long service life, so it is very suitable as an excellent field emission component. In the electron-emitting part of the display device. A conventional carbon nanotube field emission element generally includes at least a conductive cathode electrode and a carbon nanotube as a emitting end, and the carbon nanotube is formed on the cathode electrode. At present, the preparation methods of the carbon nanotube field emission elements mainly include mechanical methods and in situ growth methods. Among them, mechanical methods include screen printing and gluing. Screen printing is generally carried out by mixing a carbon nanotube powder into a slurry and printing it onto a conductive cathode by screen printing. This 200800798 to pass through the 舄 to configure a uniform dispersion of the carbon nanotube slurry, after printing for fire, dry friction, dust removal, sintering and other steps, the process is complex, and the printing method is not suitable for making high current or high precision Field emission component. The dead gel method is to manipulate the carbon nanotubes that have been synthesized by atomic force microscopy, and fix the carbon nanotubes to the conductive cathode with a conductive paste. The hexagonal wire is simple, but the operation is complicated and the efficiency is low. The prepared emitter has a low current carrying capacity. In addition, during the operation of the viscose method, the chemical layer penetrates into the tiny carbon nanotube gap towel, and the surface tension easily changes the carbon nanotube emitter. shape. In addition, since the chemical glue generally cannot withstand the sealing or exhaust temperature required for the electronic vacuum component (generally 30{rc~50(rc), the practical application of the method is limited. The metal catalyst is plated on the conductive cathode, and then the carbon nanotube is directly grown on the conductive cathode by chemical vapor deposition, arc discharge or laser ablation. The method is simple to operate, and the carbon carbon and the conductive cathode are conveniently operated. The electrical contact is good. However, the binding ability of the carbon nanotubes to the conductive cathode is weak, and the carbon nanotubes are easily detached or pulled out by the electric field force during use, thereby causing damage to the field emission element. Moreover, since the method is difficult to control The number and direction of growth of the carbon nanotubes, so there are still problems of low efficiency and poor controllability. In addition, the in-situ growth method has a choice of cathode substrate materials, which need to be used without affecting the chemical vapor phase conditions; Ming, oxidized stone, high-melting point metal, etc., or the surface of the substrate is coated with a layer of isolation. Moreover, the substrate material also needs to be able to withstand the high temperature range of carbon nanotube growth, so the method The cost is high, which is not conducive to practical application. There is a cloud here, for a field emission component which is easy to be fixed on the conductive cathode and electrical connection 8 200800798 Good, current carrying capacity is south, production and operation is simple, and is easy to be practically applied and preparation method thereof [Explanation] Hereinafter, a field emission element and a preparation method thereof will be described in several embodiments, 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. The field emission element 'comprising at least - a carbon nanotube field emission wire and at least a branch (four) wire, the nano carbon tube field emission line supporting the Lin #相魏卿 ❹ acid line structure and the carbon nanotube field emission The wire is a carbon nanotube polymer composite material of nano carbon line. The diameter of the nanowire carbon fiber tube of the nanometer is 2 to 200 micrometers. The nanometer polymer composite material comprises a polymer material uniformly dispersed in the composition. (4) The carbon nanotubes of the towel. ° The diameter of the nanotube is 5~40 nm. The ratio of the 1:1 of the polymer composite (4) is 1-4%. The support material is copper, silver, gold, recorded or married. The nozzle material is poly-p-ethylene glycol vinegar, poly-O-ester, acrylonitrile-butyl-sodium sulphate (tetra) nitrile, olefin copolymer Or concentrating, providing at least; shooting two: two preparation methods, comprising the following steps: australis green, emission wire and at least one support line, x art, the carbon nanotube field emission wire and the support 9 200800798 The wires are intertwined to form a multi-stranded strand structure; the strands of the carbon nanotube field emission wire and the support body wire are entangled with each other according to a predetermined long sound to form a field emission element. Including mechanical shearing or laser cutting. Compared with the prior art, the field emission element comprising the support wire and the carbon nanotube field emission wire has the advantages that: first, the carbon nanotube field emission wire is used as the emission. The bulk electron emission can utilize the excellent electron emission performance of the carbon nanotube itself; secondly, the multi-strand strand structure formed by the support wire and the nano carbon tube field emission wire has a macroscopic size, and the support wire is used for the carbon nanotube field. emission Protective effect of solid material and Cloth 'cause the field emission device having good mechanical properties moonlight' easily fixed to a cathode electrode 'easy, and mass production can be easily applied to various vacuum field emission devices. [Embodiment] Hereinafter, the present invention will be further described in detail with reference to the accompanying drawings. Please refer to FIG. 1 and FIG. 2 'The first embodiment of the present invention provides a field emission element 10 including a carbon nanotube field emission wire 12 and spirally wound around the carbon nanotube field emission wire. At least one support wire 14 of 12. The carbon nanotube field emission wire 12 is used to emit electrons. The branch body 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 10. The plurality of support 200800798 support wires 14 are wound around the periphery of the nano tube-breaking wire 12. e The support wire 14 may be made of copper, silver, gold, nickel, molybdenum or its other metal 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 the 10 actual needs, the carbon nanotube 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 It is 2 to 200 microns. In the present embodiment, the carbon nanotube field emission wire 12 can also be replaced with 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 terephthalate (Polyethylene Terephthalate), polycarbonate (Polycarbonate, PC), acrylonitrile-butadiene propylene-styrene copolymer (Acrylonitrile). -Butadiene Styrene Terpolymer, ABS), polycarbonate / acrylonitrile butadiene - stupid ethylene copolymer (PC / ABS) and other polymer materials. Among them, the mass percentage of the carbon nanotubes in the composite material is from 1% to 10%, and in this embodiment, it is preferably 2%. In the application of the field emission device of the present embodiment, a single field device or a plurality of field emission devices may be disposed on the cathode electrode through the support body wire 14 to form a single field emission electron source or a planar array of field emission electrons. The source, and the carbon nanotube field emission wire '12 is electrically connected to the cathode electrode, the voltage is directly applied to the carbon nanotube field emission wire 12 through the cathode electrode, or the voltage is applied to the carbon nanotube through the support wire 14 The 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 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 carbon nanotube 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 nanotube tubes with a pair of tweezers, and applying external force pulling. Due to the role of Van der Waals force, Nai's breaks the end of the bundle and the ends are connected together to form a nanometer reward line along the drawing direction. The above-mentioned carbon nanotube array capable of drawing a nano carbon line needs to satisfy 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 of the drawing tool, and the smaller the tip size, the smaller the straight pull of the obtained carbon carbon line. The length of the nano carbon tube wire is extracted from a nano carbon line having a length of 10 m (m) by a nano carbon tube array of an area of 6 carbon tube arrays, usually 1 cm 2 (cm 2 ). The force of pulling the carbon nanotubes 12 200800798 Size is determined by the diameter of the carbon nanotubes. The larger the diameter, the greater the force required. The diameter of the nano barrier line in this embodiment is preferably in the range of 2 to 2 0 0 μm. ^ The method for preparing the linear carbon nanotube polymer composite of the present embodiment comprises the steps of: providing a uniformly dispersed prepolymer solution or a prepolymer monomer solution; adding a carbon nanotube to the solution and uniformly dispersing The prepolymer solution is polymerized to form a polymer, and extruded by an extrusion apparatus to form a linear carbon nanotube polymer composite. • The preparation method of the carbon nanotubes can be carried out by chemical vapor deposition, arc discharge, laser ablation, 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 ~40 nm. The polymer material of this embodiment may be selected from the group consisting of polyethylene terephthalate (PET), polycarbonate (Polycarbonate, PC), acrylonitrile-butadiene propylene-styrene copolymer (Acrylonitrile). -Butadiene Styfene ® 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 material fiber having a diameter of 2 to 200 micrometers, wherein the mass percentage of the carbon nanotubes in the composite material is 1% to 10%. This embodiment is preferably 2%. 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, nickel, 13 200800798 molybdenum or other metal materials. The shape of the support wire 14 is linear, and its diameter and length can be selected according to actual needs. The diameter of the support 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 branch 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 are twisted together by a spinning process to form a plurality of strands. < According to the actual needs, the length of the required field emission component can be made directly. For the convenience of production, the long line can be made first, and then cut by the mechanical shear laser cutting method into the field emission component of the required length. . Referring to FIG. 4, a second embodiment of the present invention provides a field emission element 20 that includes at least one 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 10 of the first embodiment of the present invention, except that the field emission element 20 of the second embodiment is emitted by one or more carbon nanotube fields. The wire 22 replaces the support strand wire 4 located at the periphery of the field emission element 10 in the embodiment, and the 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 support wire 24 are the same as those of the first embodiment, and the preparation method of the true field emission element 20 is also the same as that of the field emission element 14 of the first embodiment. 200800798 Pieces 10 are substantially identical 'only need to replace one or more carbon nanotube field emission wires 22 with the adjacent support wires 24 to form a plurality of strands. Stranded wire structure. The present invention comprises a field emission element of a support wire and a carbon nanotube field emission wire. The advantage is that the first use of a carbon nanotube field emission wire as an emitter to emit electrons can utilize the excellent electron emission of the carbon nanotube itself. Secondly, the multi-stranded 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 support Φ support wire, so that the field emission component has good performance. The mechanical properties, easy to operate, can be mass produced and conveniently applied to various 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. Equivalent modifications or variations made by those skilled in the art to the spirit of the invention are intended to be included within the scope of the following claims. 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 of Figure 1 along the ΙΙ-Π line. 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. 15 200800798 w [Explanation 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
1616