1362684 100年.11月07日按正替$頁 六、發明說明： 【發明所屬之技術領域】 [0001] 本發明涉及一種場發射電子源的製備方法，尤其涉及一 種基於奈米碳管的場發射電子源的製備方法。 【先前技術】 [0002] 場發射電子源在低溫或者室溫下工作，與電真空器件中 的熱發射電子源相比具有能耗低、回應速度快以及低放 電等優點，因此用場發射電子源替代電真空器件中的熱 發射電子源成為了人們研究的一個埶點。 [0003] 奈米碳管（Carbon Nanotube，CNT)係—種新型碳材料 ，由曰本研究人員1丨〗丨111&在1991年發現，請參見"^^1_ ical Microtubules of Graphitic Carbon", S.1362684 100年.11月07日正正$$6, invention description: [Technical field of invention] [0001] The present invention relates to a method for preparing a field emission electron source, and more particularly to a field based on a carbon nanotube A method of preparing an electron emission source. [Prior Art] [0002] A field emission electron source operates at a low temperature or a room temperature, and has the advantages of low power consumption, fast response speed, and low discharge compared with a heat-emitting electron source in an electric vacuum device, so that field emission electrons are used. The source of heat-emitting electrons in the replacement of electric vacuum devices has become a flaw in research. [0003] Carbon Nanotube (CNT) is a new type of carbon material, which was discovered by the researcher 1丨丨111& in 1991, see "^^1_ ical Microtubules of Graphitic Carbon", S.
Iijima’ Nature, vol.354，p56 ( 1 991 )。奈米碳管 具有極優異的導電性能、良好的化學穩定性和大的長徑 比，且其具有幾乎接近理論極限的尖端表面積（尖端表面 積愈小，其局部電場愈集中），因而奈米碳管在場發射真 φ 空電子源領域具有潛在的應用前景《目前的研究表明， 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），可傳輸極大的電流密度，並且電流極穩定， 使用壽命長’因而非常適合作為一種極佳的點電子源， 應用在掃描電子顯微鏡（Scanning Electron Microscope) 、 透射電子顯微鏡 （Transmission ElectronIijima’ Nature, vol.354, p56 (1 991 ). The carbon nanotubes have excellent electrical conductivity, good chemical stability and large aspect ratio, and have a tip surface area close to the theoretical limit (the smaller the tip surface area, the more concentrated the local electric field), thus the nanocarbon Tube field emission has a potential application prospect in the field of true φ empty electron source. Current research shows that the carbon nanotube system is one of the best field emission materials known, and its tip size is only a few nanometers to several tens of nanometers. Meter, with extremely low field emission voltage (less than 100 volts), can transmit extremely large current density, and has extremely stable current and long service life. It is therefore very suitable as an excellent point electron source for scanning electron microscope (Scanning). Electron Microscope), Transmission Electron Microscope (Transmission Electron)
Microscope)等設備的電子發射部件中β [0004] 096142408 先則的奈米碳管場發射電子源一般至少包括一導電基體The electron emission component of a device such as Microscope) [0004] 096142408 The prior carbon nanotube field emission electron source generally includes at least one conductive substrate
表單編號咖1 % 3 1/^ 25 I 1003412031-0 知Μ心 卜11月 -、發射端的奈米碳管，該奈米碳管形該導電; 體上目則，奈米碳管形成於導電基體上的方法主要包 括機械方姊純生長法。其巾，機财絲通過原子 力顯微鏡或電子賴鏡操縱單根奈米碳管，將奈米碳管 用導電軸定到導電基體上，此種方法程式簡單，但由 於單根τ'米碳管尺寸太小，導致操作不容易且效率低。 另外，通過該方法得到的奈米碳管場發射電子源的場發 射電流小。 [0005] 為克服上述機械法組裝的奈米碳管場發射電子源的場發 射電流小及操作複雜的缺點。先前技術提供了一種採用 β 原位生長的方法，該方法係先在導電基體上鍍上金屬催 化劑，然後通過化學氣相沈積、電弧放電或鐳射蒸發法 等方法在導電基體上直接生長出多根奈米碳管作為場發 射電子源，此種方法雖然操作簡單，奈米碳管與導電基 體的電接觸良好。然而，奈米碳管與導電基體的結合能 力較弱’在使用時奈米碳管易脫落或被電場力拔出，從 而導致場發射電子源損壞。而且，由於該方法無法控制 | 奈米碳管的生長方向’所以仍存在效率低且可控性差的 問題，另外’這種場發射電子源結構中多根奈米碳管之 間存在電場屏蔽效應’工作時往往只有少部分奈米碳管 發射電子’亦無法有效提高場發射電子源的電流密度。 [0006] 有鑒於此，提供一種具有較大的場發射電流的場發射電 子源的製備方法實為必要。 【發明内容】 一種場發射電子源，包括一導電基體和一奈米碳管長線 096142408 表單编號Α0101 第4頁/共25頁 1003412031-0 [0007] 1362684 100年.11.月07日核正_頁 。該奈米碳管長線具有一第一端以及與第一端相對的第 二端，該奈米碳管長線的第一端與該導電基體電連接， 該奈米碳管長線的第二端從導電基體向外延伸，該奈米 碳管長線的第二端包括多個突出的場發射尖端。 [0008] 一種場發射電子源的製備方法，其具體包括以下步驟： 提供一奈米碳管陣列形成於一基底；採用一拉伸工具從 奈米碳管陣列中拉取奈米碳管獲得一奈米碳管薄膜或者 一奈米碳管絲；通過使用有機溶劑或者施加機械外力處 • 理該奈米碳管薄膜或者奈米碳管絲得到一奈米碳管長線 ;將該奈米碳管長線通電流加熱熔斷，在熔斷處形成多 個場發射尖端；以及將該熔斷後的奈米碳管長線設置於 導電基體上即得到場發射電子源。 [0009] • 與先前技術相比較，該場發射電子源及其製備方法具有 以下優點：其一，採用了奈米碳管長線作為場發射電子 源，該奈米碳管長線包括多個突出的場發射尖端，所製 備的場發射電子源具有較大的場發射電流；其二，該奈 米碳管長線中包括多個場發射尖端，可以有效降低該場 發射電子源的電場屏蔽效應；其三，奈米碳管長線為宏 觀器件，操作簡單，因此，該場發射電子源的製備方法 簡單，可以提高該場發射電子源的製備效率。 [0010] 【實施方式】 以下將結合附圖詳細說明本技術方案場發射電子源及其 製備方法。 [0011] 請參閱圖1，本技術方案實施例提供一種場發射電子源10 096142408 ，其包括一導電基體14和一奈米碳管長線12。該奈米碳 表單編號A0101 第5頁/共25頁 1003412031-0 1362684 100年11月07日核正替换頁 管長線12具有一第一端122以及與第一端122相對的第二 端124，該奈米破管長線12的第一端122與該導電基體14 電連接，該奈米碳管長線12的第二端124從導電基體14向 外延伸作為電子發射端。 [0012]進一步地，所述的奈米碳管長線12係由多個平行的首尾 相連的奈米碳管束組成的束狀結構或由多個首尾相連的 奈米碳管束組成的絞線結構，該相鄰的奈米碳管束之間 通過凡德瓦爾力緊密結合，該奈米碳管束中包括多個首 尾相連且定向排列的奈米碳管。該奈米碳管長線12的長 度為0.1毫米至10毫米，直徑為1微米至1〇〇微米。所述 的奈米碳官長線12的第·一端124為類圓錐形，且其直徑沿 遠離導電基體14的方向逐漸減小《請參閱圖2，該奈米碳 官長線12的第一端124包括多個突出的場發射尖端β 6玄％發射尖端300包括多個基本平行的奈米碳管，該多個 奈米碳管之間通過凡德瓦爾力緊密結合。所述的場發射 尖端300為類圓錐形。該場發射尖端3〇〇的頂端突出有一 根奈米碳管302。該奈米碳管3〇2長度範圍為1〇〜1〇〇微米 ’奈米奴管302的尖端直徑小於5奈米。該奈米碳管長線 12中的奈米碳管為單壁、雙壁或多壁奈米碳管。該奈米 碳管長線12中的場發射尖端300的頂端的奈米碳管與其他 遠離該場發射尖端300的頂端的奈米碳管緊密結合，使得 該場發射尖端300的頂端的奈米碳管在場發射過程中產生 的熱量可以很有效地被傳導出去，並且可以承受較強的 電場力。 [0013] 096142408 請參閱圖3，從奈米碳管長線12的電子發射端的掃描電鏡 表單編號Α0101 第6頁/共25頁 1003412031-0 1362684 100’年.11月07日接正雜頁 照片可以看出該電子發射端包括多個突出的場發射尖端 。清參閱圖4，從奈米碳管長線12的電子發射端的透射電 鏡照片上，可以看出奈米碳管長線12中的場發射尖端的 頂端突出有一根奈米碳管。該奈米碳管具有更少的壁數 和更細的直控，其壁數少於5層一般為2層或者3層，其直 瓜通*小於5奈米。而直接生長的超順排奈米碳管陣列的 奈米碳管的層數多於5層’直徑為15奈米左右。 [0014] 該導電基體14由導電材料製成，如鎳、銅、鎢、金、鉬 • 、翻等。該導電基體14可依實際需要設計成其他形狀， 如錐形 '細小的柱形或者圓臺形。該導電基體14也可為 形成在一絕緣基底上的導電薄膜。 [0015] 可以理解，該奈米碳管長線12的第一端122可以通過一導 電膠與該導電基體14電連接。該電連接的方式也可以通 • 過分子間力或者其他方式實現.該奈米碳管長線12與導 電基體14之間的位置關係不限，只需確保該奈米碳管長 線12的第一端122與該導電基體14電連接即可。如奈米碳 管長線12與導電基體14的夾角為銳角，奈米碳管長線I〗 與導電基體14的夾角為直角或者奈米碳管長線12與導電 基體14的轴向相互平行。 [0016] 本實施例中，由於採用了奈米碳管長線作為場發射電子 源，該奈米碳管長線包括多個突出的場發射尖端，所製 備的場發射電子源具有較大的場發射電流；而且，該奈 米碳管長線中包括多個場發射尖端，可以有效降低該場 發射電子源的電場屏蔽效應。 096142408 表單編號删1 第7頁/共25頁 1〇麵腦_〇 1362684 100年.11.月07日梭正替換頁 [0017] 請參閲圖5，本技術方案實施例提供一種製備上述場發射 電子源10的方法，具體包括以下步驟： [0018] 步驟一：提供一奈米碳管陣列形成於一基底，優選地， 該陣列為超順排奈米碳管陣列。 .Form number coffee 1% 3 1/^ 25 I 1003412031-0 Knowing the heart of November - the carbon nanotube at the launch end, the carbon nanotube shape is electrically conductive; on the body, the carbon nanotube is formed on the conductive The method on the substrate mainly includes a mechanical square pure growth method. The towel, the machine wire manipulates a single carbon nanotube through an atomic force microscope or an electronic microscope, and the carbon nanotube is fixed to the conductive substrate by a conductive shaft. This method is simple, but due to the size of a single τ' meter carbon tube Too small, resulting in an operation that is not easy and inefficient. Further, the field emission electron current of the carbon nanotube field emission electron source obtained by this method is small. [0005] To overcome the shortcomings of the small field emission current and complicated operation of the carbon nanotube field emission electron source assembled by the above mechanical method. The prior art provides a method of in-situ growth of β by first plating a metal catalyst on a conductive substrate, and then directly growing a plurality of layers on the conductive substrate by chemical vapor deposition, arc discharge, or laser evaporation. The carbon nanotube is used as a field emission electron source. Although the method is simple, the electrical contact between the carbon nanotube and the conductive substrate is good. However, the binding ability of the carbon nanotubes to the conductive substrate is weak. In use, the carbon nanotubes are easily detached or pulled out by the electric field force, thereby causing damage to the field emission electron source. Moreover, since the method cannot control the growth direction of the carbon nanotubes, there is still a problem of low efficiency and poor controllability, and there is an electric field shielding effect between the plurality of carbon nanotubes in the field emission electron source structure. 'Working with only a small number of carbon nanotubes emitting electrons' can not effectively increase the current density of the field emission electron source. In view of this, it is necessary to provide a method of preparing a field emission electron source having a large field emission current. SUMMARY OF THE INVENTION A field emission electron source includes a conductive substrate and a carbon nanotube long line 096142408 Form No. 1010101 Page 4/Total 25 Page 1003412031-0 [0007] 1362684 100 years.11. _page. The carbon nanotube long wire has a first end and a second end opposite to the first end, the first end of the long carbon nanotube line is electrically connected to the conductive substrate, and the second end of the long carbon nanotube line is The electrically conductive substrate extends outwardly, and the second end of the long section of the carbon nanotube comprises a plurality of protruding field emission tips. [0008] A method for preparing a field emission electron source, comprising the steps of: providing a carbon nanotube array formed on a substrate; and using a stretching tool to extract a carbon nanotube from the carbon nanotube array to obtain a a carbon nanotube film or a nano carbon tube wire; a long carbon nanotube line is obtained by using an organic solvent or applying a mechanical external force to obtain the nano carbon tube film or the nano carbon tube wire; The line current is heated and blown, and a plurality of field emission tips are formed at the fuse; and the blown carbon nanotube long line is disposed on the conductive substrate to obtain a field emission electron source. [0009] Compared with the prior art, the field emission electron source and the preparation method thereof have the following advantages: First, a carbon nanotube long line is used as a field emission electron source, and the nano carbon tube long line includes a plurality of protruding At the field emission tip, the prepared field emission electron source has a large field emission current; secondly, the nano carbon tube long line includes a plurality of field emission tips, which can effectively reduce the electric field shielding effect of the field emission electron source; Third, the long line of the carbon nanotube is a macroscopic device, and the operation is simple. Therefore, the preparation method of the field emission electron source is simple, and the preparation efficiency of the field emission electron source can be improved. [Embodiment] Hereinafter, a field emission electron source of the present technical solution and a preparation method thereof will be described in detail with reference to the accompanying drawings. Referring to FIG. 1 , an embodiment of the present technical solution provides a field emission electron source 10 096142408 including a conductive substrate 14 and a carbon nanotube long line 12 . The nanocarbon form number A0101, page 5 / total 25 pages 1003412031-0 1362684, November 07, 100, the nuclear replacement page tube long line 12 has a first end 122 and a second end 124 opposite the first end 122, The first end 122 of the long tube 12 is electrically connected to the conductive substrate 14. The second end 124 of the long carbon tube 12 extends outwardly from the conductive substrate 14 as an electron-emitting end. [0012] Further, the carbon nanotube long line 12 is a bundle structure composed of a plurality of parallel end-to-end connected carbon nanotube bundles or a strand structure composed of a plurality of end-to-end connected carbon nanotube bundles. The adjacent carbon nanotube bundles are tightly coupled by van der Waals force, and the carbon nanotube bundle includes a plurality of carbon nanotubes connected end to end and oriented. The carbon nanotube long wire 12 has a length of 0.1 mm to 10 mm and a diameter of 1 μm to 1 μm. The first end 124 of the nano-carbon longitudinal line 12 is conical-shaped, and its diameter gradually decreases away from the conductive substrate 14. Referring to FIG. 2, the first end 124 of the nano-carbon long line 12 is 124. A plurality of protruding field emission tips, including a plurality of substantially parallel carbon nanotubes, are closely coupled between the plurality of carbon nanotubes by van der Waals forces. The field emission tip 300 is conical like a cone. A carbon nanotube 302 protrudes from the top end of the field emission tip. The carbon nanotube 3〇2 has a length ranging from 1 〇 to 1 〇〇 micrometer. The tip diameter of the nanotube 302 is less than 5 nm. The carbon nanotubes in the long carbon nanotube 12 are single-walled, double-walled or multi-walled carbon nanotubes. The carbon nanotubes at the top end of the field emission tip 300 in the long carbon nanotube line 12 are tightly coupled to other carbon nanotubes remote from the top end of the field emission tip 300 such that the nanocarbon at the top end of the field emission tip 300 The heat generated by the tube during field emission can be conducted very efficiently and can withstand strong electric field forces. [0013] 096142408 Please refer to FIG. 3, the scanning electron microscope form number from the electron emission end of the long carbon tube 12 of the carbon nanotubes Α 0101 Page 6 / 25 pages 1003412031-0 1362684 100' year. November 07 It is seen that the electron emitting end includes a plurality of protruding field emission tips. Referring to Fig. 4, it can be seen from the transmission electron micrograph of the electron-emitting end of the long carbon nanotube 12 of the carbon nanotube that a carbon nanotube is protruded from the tip end of the field emission tip in the long carbon nanotube 12 of the carbon nanotube. The carbon nanotubes have a smaller number of walls and a finer direct control, and the number of walls is less than 5 layers, generally 2 or 3 layers, and the diameter of the melon is less than 5 nm. The directly grown super-sequential carbon nanotube array has a number of layers of carbon nanotubes of more than 5 layers and a diameter of about 15 nm. [0014] The conductive substrate 14 is made of a conductive material such as nickel, copper, tungsten, gold, molybdenum, turn, and the like. The conductive substrate 14 can be designed into other shapes according to actual needs, such as a tapered 'small cylindrical shape or a truncated cone shape. The conductive substrate 14 can also be a conductive film formed on an insulating substrate. [0015] It can be understood that the first end 122 of the carbon nanotube long wire 12 can be electrically connected to the conductive substrate 14 through a conductive paste. The electrical connection can also be realized by intermolecular force or other means. The positional relationship between the long carbon nanotube 12 and the conductive substrate 14 is not limited, and only the first long carbon 12 of the carbon nanotube is ensured. The terminal 122 is electrically connected to the conductive substrate 14. For example, the angle between the long line 12 of the carbon nanotube and the conductive substrate 14 is an acute angle, the angle between the long line I of the carbon nanotube and the conductive substrate 14 is a right angle, or the long line 12 of the carbon nanotube is parallel to the axial direction of the conductive substrate 14. [0016] In this embodiment, since a long carbon nanotube line is used as a field emission electron source, the nano carbon tube long line includes a plurality of protruding field emission tips, and the prepared field emission electron source has a large field emission. The current; moreover, the carbon nanotube long line includes a plurality of field emission tips, which can effectively reduce the electric field shielding effect of the field emission electron source. 096142408 Form number deletion 1 Page 7 / Total 25 pages 1 〇 脑 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ The method for emitting the electron source 10 specifically includes the following steps: [0018] Step 1: providing a carbon nanotube array formed on a substrate, preferably, the array is a super-sequential carbon nanotube array. .
[0019] 本實施例中，奈米碳管陣列的製備方法採用化學氣相沈 積法，其具體步驟包括：（a)提供一平整基底，該基底 可選用P型或N型矽基底，或選用形成有氧化層的矽基底 ，本實施例優選為採用4英寸的矽基底；（b)在基底表 面均勻形成一催化劑層，該催化劑層材料可選用鐵（Fe · )、钻（Co)、錄（Ni)或其任意組合的合金之一；（c )將上述形成有催化劑層的基底在700°C~900°C的空氣中 退火約30分鐘~90分鐘；（d)將處理過的基底置於反應 爐中，在保護氣體環境下加熱到500°C〜740°C，然後通入 碳源氣體反應約5分鐘-30分鐘，生長得到奈米碳管陣列 ，其高度大於100微米。該奈米碳管陣列為多個彼此平行 且垂直於基底生長的奈米碳管形成的純奈米碳管陣列。 該奈米碳管陣列與上述基底面積基本相同。通過上述控 ® 制生長條件，該超順排奈米碳管陣列中基本不含有雜質 ，如無定型碳或殘留的催化劑金屬顆粒等。 [0020] 本實施例中碳源氣可選用乙炔、乙烯、甲烷等化學性質 較活潑的碳氫化合物，本實施例優選的碳源氣為乙炔； 保護氣體為氮氣或惰性氣體，本實施例優選的保護氣體 為氬氣。 [0021] 可以理解，本實施例提供的奈米碳管陣列不限於上述製 096142408 表單编號Α0101 第8頁/共25頁 1003412031-0 13-62684 100年11月07日梭正替換頁 備方法。本實施例提供的奈米碳管陣列為單壁奈米碳管 陣列、雙壁奈米碳管陣列及多壁奈米碳管陣列中的一種 [0022] 步驟二：採用一拉伸工具從奈米碳管陣列中拉取奈米碳 管獲得一奈米碳管薄膜或一奈米碳管絲。 [0023] 該奈米碳管薄膜或者奈米碳管絲的製備具體包括以下步 驟：（a)從上述奈米碳管陣列中選定一定寬度的多個奈 米碳管片斷，本實施例優選為採用具有一定寬度的膠帶 接觸奈米碳管陣列以選定一定寬度的多個奈米碳管束； (b )以一定速度沿基本垂直於奈米碳管陣列生長方向拉 伸多個該奈米碳管束，以形成一連續的奈米碳管薄膜或 者奈米碳管絲。 [0024] 在上述拉伸過程中，該多個奈米碳管束在拉力作用下沿 拉伸方向逐漸脫離基底的同時，由於凡德瓦爾力作用， 該選定的多個奈米碳管束分別與其他奈米碳管束首尾相 連地連續地被拉出，從而形成一奈米碳管薄膜或者一奈 米碳管絲。該奈米碳管薄膜或者奈米碳管絲包括多個首 尾相連且定向排列的奈米碳管束。該奈米碳管薄膜或者 奈米碳管絲中奈米碳管的排列方向基本平行於奈米碳管 薄膜或者奈米碳管絲的拉伸方向。 [0025] 步驟三，通過使用有機溶劑或者施加機械外力處理該奈 米碳管薄膜或者奈米碳管絲得到一奈米碳管長線12。 [0026] 所述步驟二中製備的奈米碳管薄膜或者奈米碳管絲可使 '用有機溶劑處理得到一奈米碳管長線12。其具體處理過 096142408 表單編號 A0101 第 9 頁/共 25 頁 1003412031-0 1362684 _:_一 100年.11.月07日梭正替換頁 程包括：通過試管將有機溶劑滴落在奈米碳管薄膜或者 奈米碳管絲表面浸潤整個奈米碳管薄膜或者奈米碳管絲 。可以理解，也可以將上述奈米碳管薄膜或奈米碳管絲 整個浸入盛有有機溶劑的容器中浸潤。該有機溶劑為揮 發性有機溶劑，如乙醇、甲醇、丙酮、二氣乙烷或氣仿 ，本實施例中優選採用乙醇。該奈米碳管薄膜或者奈米 碳管絲經有機溶劑浸潤處理後，在揮發性有機溶劑的表 面張力的作用下，奈米碳管薄膜或者奈米碳管絲中的平 行的奈米碳管片斷會部分聚集成奈米碳管束，因此，該 奈米碳管薄膜或者奈米碳管絲表面體積比小，無黏性， € 且具有良好的機械強度及韌性，應用有機溶劑處理後的 奈米碳管薄膜或者奈米碳管絲能方便地應用於宏觀領域 〇 [0027] 所述步驟二中製備的奈米碳管薄膜或者奈米碳管絲也可 通過施加機械外力處理得到一奈米碳管長線12。提供一 個尾部可以黏住奈米碳管陣列的紡紗軸。將該紡紗軸的 尾部與奈米碳管陣列結合後，奈米碳管開始纏繞在軸的 4 周圍。將該紡紗軸以旋轉的方式旋出並向遠離奈米碳管 陣列的方向運動。這時奈米碳管陣列相對於該紡紗軸移 動時，纖維開始紡成，其他的奈米碳管可以纏繞在纖維 的周圍，增加纖維的長度。可以理解，上述紡紗軸的旋 轉方式不限，可以正轉，也可以反轉，或者正轉和反轉 相結合。 [0028] 可以理解，也可以採用一拉伸工具從步驟一的奈米碳管 陣列中直接拉取奈米碳管獲得一奈米碳管長線12。 096142408 表單編號A0101 第10頁/共25頁 1003412031-0 [0029] [0030] [0031] [0032] [0033] [0034] 1100^.11^ 07 B步驟四：將該奈米碳管長線12通電流加熱熔斷，在熔斷 處形成多個場發射尖端。 "亥步騾可以在真空環境下或惰性氣體保護的環境下進行 ’其具體包括以下步驟：首先，請參見圖6及圖7 ,將該奈米碳管長線12懸空設置 於一真空室50内或充滿惰性氣體的反應室。 該真空室50包括—可視視窗（圖令未標出）以及一陽極 接線柱52與—陰極接躲54，且其真空度低於lxl0-i帕 ’優選為2X10'5帕。該奈米碳管長線12兩端分別與陽極 接線柱52和陰極接線柱54電性連接。本實施例中，該陽 極接線柱52與陰極接線柱54為直徑Q. 5毫来的銅絲導線， 該奈米碳管長線12的直徑25微米，長度2厘米。所述的充滿隋性氣體的反應室結構與真空室5G相同，惰 性氣體可則錢氣錢氣等。其-人，在該奈米碳管長線12兩端施加-電壓，通入電流 加熱熔斷。 义陽極接線柱52與陰極接線柱54之間施加-4G伏特的直 叫電壓。本技術領域人貝應當明白，陽極接線柱52與陰 極接線柱54之間施加的電壓與所選的奈米碳管長線12的 =和長度有關。在直流條件下通過焦耳熱加熱奈米碳 S長線12。加熱溫度優選為2000K至2400K，加熱時間小 ;1 ]時。在真空直流加熱過程中’通過奈米碳管長線12 ★、電机會逐漸上升，但报快電流就開始下降直到奈米碳 096142408 *長線12被熔斷。在熔斷前，奈米碳管長線12上會出現 1003412031-0 表單編號細 .11 Ι/Λ 25 , 丄362684 1100年11月07日按正 一個党點56，奈米碳管長線12從該亮點56處熔斷。 _]由於奈米碳管長線12中各點的電阻不同，使得各點的分 電壓也不同。在奈米碳管長線12中電阻較大的一點，會 得到較大的分電壓，從而具有較大的加熱功率，產生較 多的焦耳熱’使該點的溫度迅速升高。在_的過程中 ，該點的電P時絲越大，導致該點的分電壓也越來越 大，同時，溫度也越來越大直到該點斷裂，形成兩個電 子發射端。在熔斷的瞬間，陰極與陽極之間會產生一個 非常小的間隙’同時在炫斷點位置附近，由於碳的蒸發 ’真空度較差，這些因素會使熔斷的瞬間在熔斷點附近 產生氣體電離。電離後的離子轟擊炫斷的奈米碳管長線 12的端部，並在該端部形成多個場發射尖端3〇(^ [0037] .本實施例採用的真空溶斷法，避免了奈米碳管長線12溶 斷口的污染’而且’加熱過程中奈米碳管長線12的機械 強度會有一定提高’使之具備優良的場發射性能。 [0038] 步驟五：將熔斷後的奈米碳管長線12設置於—導電基體 14上即得到一場發射電子源10。 # [0039] 將熔斷後的奈来碳管長線12通過—導電膠黏附於一導電 基體14之上，即可得到一場發射電子源1〇。 [0040] 可以理解，也可將多個具有電子發射端的奈米碳管長線 12設置於一導電基體14之上，得到具有客伽 ’夕個電子發射端 的場發射電子源。 [0041] 096142408 本實施例中，由於奈米碳管長線12為宏觀 容易的被黏附於導電基體14上，操作簡單表單编號A0101 第12頁/共25頁 器件，可以很 ’因此，該場 1003412031-0 1362684 1100年11.月07日修正 發射電子源的製備方法簡單，可以提高該場發㈣子源 的製備效率。 _]請參閱圖8 ’為奈米碳管長線12的場發射尖端3〇〇的拉曼 光譜圖。用拉曼光譜分析表明經過熱處理的奈米碳管長 線12的場發射尖端300的缺陷峰有明顯的降低，而尖端的 缺陷峰更低。也就說’奈来碳管長線12的場發射尖端3〇〇 的奈米破管在炫斷的過程中品f得到了極大的提高。這 一方面係由於奈米碳管經過熱處理後缺陷減少，另一方 面係因為富含缺陷的石墨層容易在高溫下崩潰，剩下一 些品質較高的石墨層。 圆轉閱圖9，為上述場發射電子_場發射性能測試結果 圖。該奈米碳管長線12經過定點熔斷處理後形成兩個電 子發射端。該場發射電子源的場發射性能測試係用一個 鎢針尖作為陽極進行測量的，其中該鎢針尖分別與該兩 個電子發射端相對。該鎢針尖與該奈米碳管長線12的尖 端之間的距離為100微米。真空熔斷形成的兩個電子發射 端均可以提供150微安以上的場發射電流。由於該奈米碳 管長線12的電子發射端的直徑大約為5微米，因此該場發 射電流的密度大於700安/平方厘米。 [0044] 综上所述，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。 【圖式簡單說明】 1003412031-0 096142408 表單編號Α0101 第13頁/共25頁 1362684 [0045] [0046] 100年11月07日按正替換頁 圖1係本技術方案實施例的場發射電子源的結構示意圖。 圖2係圖1中奈米碳管長線的電子發射端Π的放大示意圖 [0047] 圖3係本技術方案實施例獲得的奈米碳管長線的電子發射 端的掃描電鏡照片。 [0048] 圖4係本技術方案實施例獲得的奈米碳管長線的場發射尖 端頂端的透射電鏡照片。 [0049] 圖5係本技術方案實施例的場發射電子源的製備方法的流 程示意圖。 [0050] 圖6係本技術方案實施例奈米碳管長線通電流加熱熔斷的 示意圖。 [0051] 圖7係本技術方案實施例奈米碳管長線通電流加熱熔斷的 照片。 [0052] 圖8係本技術方案實施例獲得的奈米碳管長線的場發射尖 端的拉曼光譜圖。 [0053] 圖9係技術方案實施例的場發射電子源的電流-電壓曲線 示意圖。 【主要元件符號說明】 [0054] 場發射電子源：10 [0055] 奈米碳管長線：12 [0056] 導電基體：14 [0057] 奈米碳管長線第一端：122 096142408 表單编號A0101 第14頁/共25頁 1003412031-0 1362684 100年11月07日梭正替私頁 [0058] 奈米碳管長線第二端：124 [0059] 場發射尖端：300 [0060] 奈米碳管：302 [0061] 真空室：50 [0062] 陽極接線柱：52 [0063] 陰極接線柱：54 [0064] 亮點：56[0019] In this embodiment, the method for preparing the carbon nanotube array adopts a chemical vapor deposition method, and the specific steps thereof include: (a) providing a flat substrate, the substrate may be selected from a P-type or N-type germanium substrate, or selected The crucible substrate is formed with an oxide layer. In this embodiment, a 4 inch crucible substrate is preferably used; (b) a catalyst layer is uniformly formed on the surface of the substrate, and the catalyst layer material may be selected from iron (Fe · ), drill (Co), and recorded. (Ni) one of the alloys of any combination thereof; (c) annealing the substrate on which the catalyst layer is formed in air at 700 ° C to 900 ° C for about 30 minutes to 90 minutes; (d) treating the substrate It is placed in a reaction furnace, heated to 500 ° C to 740 ° C in a protective gas atmosphere, and then reacted with a carbon source gas for about 5 minutes to 30 minutes to grow to obtain a carbon nanotube array having a height greater than 100 μm. The carbon nanotube array is a plurality of pure carbon nanotube arrays formed of carbon nanotubes that are parallel to each other and grown perpendicular to the substrate. The carbon nanotube array is substantially the same area as the above substrate. The super-sequential carbon nanotube array is substantially free of impurities such as amorphous carbon or residual catalyst metal particles by the above-mentioned control growth conditions. [0020] In this embodiment, the carbon source gas may be selected from acetylene, ethylene, methane and other chemically active hydrocarbons. The preferred carbon source gas in this embodiment is acetylene; the shielding gas is nitrogen or an inert gas, which is preferred in this embodiment. The shielding gas is argon. [0021] It can be understood that the carbon nanotube array provided by the embodiment is not limited to the above-mentioned system 096142408 Form No. 1010101 Page 8 / Total 25 Page 1003412031-0 13-62684 November 07, 2007 Shuttle replacement method . The carbon nanotube array provided in this embodiment is one of a single-walled carbon nanotube array, a double-walled carbon nanotube array, and a multi-walled carbon nanotube array. [0022] Step 2: using a stretching tool from the nai A carbon nanotube film or a nano carbon tube wire is obtained by pulling a carbon nanotube in a carbon nanotube array. [0023] The preparation of the carbon nanotube film or the carbon nanotube wire specifically includes the following steps: (a) selecting a plurality of carbon nanotube segments of a certain width from the carbon nanotube array, the embodiment is preferably Contacting the carbon nanotube array with a tape having a certain width to select a plurality of carbon nanotube bundles of a certain width; (b) stretching a plurality of the carbon nanotube bundles at a constant speed along a growth direction substantially perpendicular to the growth of the carbon nanotube array To form a continuous carbon nanotube film or nano carbon nanotube wire. [0024] In the above stretching process, the plurality of carbon nanotube bundles are gradually separated from the substrate in the stretching direction under the action of the tensile force, and the selected plurality of carbon nanotube bundles are respectively combined with the other due to the van der Waals force The carbon nanotube bundles are continuously pulled out end to end to form a carbon nanotube film or a nano carbon tube filament. The carbon nanotube film or carbon nanotube wire comprises a plurality of carbon nanotube bundles connected end to end and oriented. The arrangement of the carbon nanotubes in the carbon nanotube film or the carbon nanotube wire is substantially parallel to the stretching direction of the carbon nanotube film or the carbon nanotube wire. [0025] Step three, obtaining a nano carbon tube long line 12 by treating the carbon nanotube film or the carbon nanotube wire with an organic solvent or applying a mechanical external force. [0026] The carbon nanotube film or the carbon nanotube wire prepared in the second step can be treated with an organic solvent to obtain a long carbon nanotube 12 of a carbon nanotube. It has been processed 096142408 Form No. A0101 Page 9 of 25 1003412031-0 1362684 _:_100 years.11. The monthly replacement page includes: the organic solvent is dropped on the carbon nanotube through the test tube The surface of the film or carbon nanotube wire is infiltrated with the entire carbon nanotube film or the carbon nanotube wire. It is to be understood that the above-mentioned carbon nanotube film or carbon nanotube wire may be entirely immersed in a container containing an organic solvent. The organic solvent is a volatile organic solvent such as ethanol, methanol, acetone, di-ethane or gas, and ethanol is preferably used in this embodiment. After the carbon nanotube film or the carbon nanotube wire is infiltrated by an organic solvent, the carbon nanotube film or the parallel carbon nanotube in the carbon nanotube wire is under the action of the surface tension of the volatile organic solvent. The segment will be partially integrated into the carbon nanotube bundle. Therefore, the surface of the carbon nanotube film or the carbon nanotube has a small volume ratio, no viscosity, and has good mechanical strength and toughness. The carbon nanotube film or the nano carbon tube wire can be conveniently applied to the macroscopic field. [0027] The carbon nanotube film or the nano carbon tube wire prepared in the second step can also be treated by applying a mechanical external force to obtain a nanometer. Carbon tube long line 12. A spinning shaft is provided that can be attached to the array of carbon nanotubes. After the tail of the spinning shaft is combined with the carbon nanotube array, the carbon nanotubes begin to wrap around the shaft 4. The spinning shaft is spun out in a rotating manner and moved in a direction away from the array of carbon nanotubes. At this time, when the carbon nanotube array is moved relative to the spinning axis, the fibers are spun, and other carbon nanotubes can be wound around the fibers to increase the length of the fibers. It can be understood that the spinning mode of the above spinning shaft is not limited, and it can be rotated forward or reversed, or combined with forward rotation and reverse rotation. [0028] It can be understood that a nanometer carbon tube long line 12 can also be obtained by directly pulling a carbon nanotube from the carbon nanotube array of the first step using a stretching tool. 096142408 Form No. A0101 Page 10 / Total 25 Page 1003412031-0 [0029] [0033] [0033] [0034] 1100^.11^ 07 B Step 4: The carbon nanotube long line 12 The current is heated and blown to form a plurality of field emission tips at the fuse. "Haibu 骡 can be carried out under vacuum environment or inert gas protection environment'. The specific steps include the following steps: First, please refer to FIG. 6 and FIG. 7 , the nano carbon tube long line 12 is suspended in a vacuum chamber 50 Inside or a reaction chamber filled with an inert gas. The vacuum chamber 50 includes a visible window (not shown) and an anode terminal 52 and a cathode junction 54, and has a vacuum of less than lxl0-iPa', preferably 2 x 10'5 Pa. The two ends of the carbon nanotube long wire 12 are electrically connected to the anode terminal 52 and the cathode terminal 54 respectively. In this embodiment, the anode terminal 52 and the cathode terminal 54 are copper wire wires having a diameter of Q. 5 millimeters. The carbon nanotube long wires 12 have a diameter of 25 micrometers and a length of 2 centimeters. The structure of the reaction chamber filled with the inert gas is the same as that of the vacuum chamber 5G, and the inert gas can be used for money and the like. It is a person who applies a voltage to both ends of the long carbon nanotube 12 of the carbon nanotube, and is blown by a current. A sense voltage of -4 GV is applied between the anode terminal 52 and the cathode terminal 54. It will be apparent to those skilled in the art that the voltage applied between the anode terminal 52 and the cathode terminal 54 is related to the length and length of the selected carbon nanotube long line 12. The nanocarbon S long line 12 is heated by Joule heat under direct current conditions. The heating temperature is preferably from 2000 K to 2400 K, and the heating time is small; During the vacuum DC heating process, the motor will gradually rise through the long line of the carbon nanotubes 12 ★, but the fast current will start to drop until the nano carbon 096142408 * long line 12 is blown. Before the fuse, the carbon nanotube long line 12 will appear 1003412031-0 Form number detail. 11 Ι / Λ 25, 丄 362684 November 7, 1100 by a party point 56, the carbon nanotube long line 12 from the highlight 56 is blown. _] Because the resistance of each point in the long line 12 of the carbon nanotubes is different, the voltages at different points are also different. At the point where the resistance in the long line 12 of the carbon nanotube is larger, a larger partial voltage is obtained, so that a larger heating power is generated, and more Joule heat is generated to cause the temperature of the point to rise rapidly. In the process of _, the larger the electric P at this point, the larger the partial voltage of the point is, and the temperature is also getting larger and larger until the point breaks, forming two electron emitting ends. At the moment of melting, a very small gap is created between the cathode and the anode. At the same time, near the position of the break point, due to the evaporation of carbon, the degree of vacuum is poor, and these factors cause gas ionization at the instant of melting near the melting point. The ionized ion bombards the end of the long carbon 12 long line 12, and forms a plurality of field emission tips 3 at the end (^ [0037]. The vacuum dissolution method adopted in this embodiment avoids the nai The pollution of the long carbon wire 12 of the carbon nanotubes is 'and the mechanical strength of the long carbon nanotubes 12 of the carbon nanotubes will be increased during the heating process' to make it have excellent field emission performance. [0038] Step 5: After the blown rice The carbon tube long line 12 is disposed on the conductive substrate 14 to obtain a field of emission electron source 10. # [0039] After the blown Nylon carbon tube long line 12 is adhered to a conductive substrate 14 through a conductive adhesive, a field can be obtained. The emission electron source 1〇 [0040] It can be understood that a plurality of carbon nanotube long wires 12 having electron emission ends can also be disposed on a conductive substrate 14 to obtain a field emission electron source having a guest gamma electron emission end. [0041] 096142408 In this embodiment, since the long carbon nanotube 12 of the carbon nanotube is easily adhered to the conductive substrate 14 in a macroscopic manner, the operation is simple, the form number A0101, page 12 / total of 25 pages, can be very Field 1003412031-0 1362684 11 00 years 11. On the 07th of the month, the preparation method of the modified electron source is simple, and the preparation efficiency of the field (four) sub-source can be improved. _] Please refer to Figure 8 for the field emission tip of the long carbon tube 12 of the carbon nanotubes. Raman spectroscopy. Raman spectroscopy shows that the defect peak of the field emission tip 300 of the heat treated carbon nanotube long line 12 is significantly reduced, while the tip has a lower defect peak. The field-emitting tip of the 12-inch nano-tube has been greatly improved in the process of stunning. This aspect is due to the reduction of defects in the carbon nanotubes after heat treatment and the lack of defects on the other hand. The graphite layer is easy to collapse at high temperature, leaving some high quality graphite layer. Turning to Figure 9, is the result of the above field emission electron_field emission performance test. The carbon nanotube long line 12 is subjected to fixed-point fuse processing. Forming two electron emitting ends. The field emission performance test of the field emission electron source is measured by using a tungsten tip as an anode, wherein the tungsten tip is respectively opposite to the two electron emitting ends. The tungsten tip and the nano carbon The distance between the tips of the long wires 12 is 100 micrometers. Both electron-emitting ends formed by vacuum melting can provide a field emission current of 150 microamperes or more. Since the electron-emitting end of the long carbon nanotubes 12 has a diameter of about 5 micrometers. Therefore, the density of the field emission current is greater than 700 A/cm 2 . [0044] In summary, the present invention has indeed met the requirements of the invention patent, and the patent application is filed according to law. However, the above is only the present invention. The preferred embodiments are not intended to limit the scope of the patent application. The equivalent modifications and variations of those skilled in the art are intended to be included within the scope of the following claims. [Simple Description of the Drawings] 1003412031-0 096142408 Form No. Α0101 Page 13/Total 25 Page 1362684 [0046] [0046] According to the replacement page of November 7, 100, the field emission electron source of the embodiment of the present technical solution is shown. Schematic diagram of the structure. 2 is an enlarged schematic view showing an electron-emitting end Π of a long carbon nanotube line in FIG. 1. [0047] FIG. 3 is a scanning electron micrograph of an electron-emitting end of a long carbon nanotube line obtained in an embodiment of the present technical solution. 4 is a transmission electron micrograph of the top end of the field emission tip of the long carbon nanotube tube obtained in the embodiment of the present technical solution. 5 is a schematic flow chart of a method for preparing a field emission electron source according to an embodiment of the present technical solution. 6 is a schematic view showing a long-pass current heating fuse of a carbon nanotube according to an embodiment of the present technical solution. [0051] FIG. 7 is a photograph of a long-term current-heating fuse of a carbon nanotube in the embodiment of the present technical solution. 8 is a Raman spectrum diagram of a field emission tip of a long carbon nanotube tube obtained by an embodiment of the present technical solution. [0052] FIG. [0053] FIG. 9 is a schematic diagram of a current-voltage curve of a field emission electron source of an embodiment of the technical solution. [Main component symbol description] [0054] Field emission electron source: 10 [0055] Nano carbon tube long line: 12 [0056] Conductive substrate: 14 [0057] Nano carbon tube long line first end: 122 096142408 Form No. A0101 Page 14 of 25 page 1003412031-0 1362684 November 07, 100, the shuttle is the private page [0058] The second end of the carbon nanotube long line: 124 [0059] Field emission tip: 300 [0060] Nano carbon tube : 302 [0061] Vacuum chamber: 50 [0062] Anode terminal: 52 [0063] Cathode terminal: 54 [0064] Highlights: 56
096142408 表單編號A0101 第15頁/共25頁 1003412031-0096142408 Form No. A0101 Page 15 of 25 1003412031-0