200823949 九、發明說明： 【發明所屬之技術領域】 • 本發明係涉及一種場發射電子源之製造方法，尤其涉 辱一種奈米碳管場發射電子源之製造方法。 【先前技術】200823949 IX. DESCRIPTION OF THE INVENTION: TECHNICAL FIELD OF THE INVENTION The present invention relates to a method of fabricating a field emission electron source, and more particularly to a method of fabricating a carbon nanotube field emission electron source. [Prior Art]
按，奈米碳管材料具有可傳輸極大電流密度、電流極 穩定、使用壽命長等特性，因而其被廣泛應用於顯微鏡、χ 射線管、微波管、CRT電子槍、太陽能轉化裝置、平板印 刷裝置、平面顯示裝置等設備中用以場發射電子源的發射 端。 傳統的由奈米碳管作爲發射端的場發射電子源一般至 少包括-導電基體及形成於導電基體頂部上作爲發射端的 維奈米碳官。奈米碳管形成於導電基體上之方法主要包 括機械方法及原位线法。其巾，機械方法係藉由原子力 顯微鏡操縱合成的奈米碳f，將合成後的奈米碳管用導電 膠固定於導電基體上，該種方法雖程式簡單，惟不易操作 ^車乂低3，藉由該方法得到的場發射電子源中的奈 未石反官係采用導電膠粘覆於導φ 太WHO &基體上，於使用過程中， 接觸狀態較差，不易充分發揮奈 木碳官的場發射性能。 干丁 由斗Γί线法_先於導電基虹鍍金屬催化劑，後夢 由化學氣相沈積、電孤放電 /後错 ，上生長-_管==法= /、電基體的電接觸良好。惟’藉由該方法得到的場發射 8 200823949 喊米碳管解電基體的結合能力㈣，於使用 =，'中〜+碳管料脫落，從㈣致場魏電子源損壞。 .如用原位生長法製造場發射電子源的生産成本亦較高。 有馨於此，確有必要提供一種成本較低、效古且 ^於操作的場發射電子社製造方法，藉由該方法^的 ==電子源中的奈米碳管與導電基合緊密且電性連 【發明内容】 之制ΙΓ藉由實施舰—步詳細說明—種場發射電子源 之錢方法’該製造方法成本較低、胁操歧且有 ^念同時’由該方法製造之場發射電子源中的奈米碳管 與V電基體結合緊密且電性連接良好。 種场發射電子源之製造方法，該製造方法係主 括以下步驟： =至少-陰極導電體，製備―”的奈輕 及導電漿料； ^ =極導電體上塗敷導電漿料，將導電_加 一導電漿料層； Λ 於導電漿料層上塗敷奈米碳管裝料，將奈米碳管嘴料 加熱，從祕導·料層上形成—奈料管漿料層；以及 將形成有導電⑽層及奈米碳管漿料相導雪體於 〜·C條件下諸烘乾無敵秘導紐表面形成 導電層及奈米碳管電子發射層，進而得到場發射電子源。 與先前技術相比較，本發明場發射電子源之製造方法 9 200823949 中藉由雙層漿料形成導電層及奈米碳管電子發射層，可實 =低成本之大面積製造，具有較高的效率，易於操作；同 時，由該方法製造之場發射電子源令導電層與奈米碳管電 f發射層結合牢固且電性連接良好。 【實施方式】 下面將結合附圖對本發明場發射電子源之製造方法作 進一步之詳細說明。 請參閱圖卜本發明場發射電子源之製造方法大致包 括以下幾個步驟： 步驟提供至少-陰極導電體、製備一定量的奈 米碳管漿料及導電漿料。 其中，陰極導電體可由金屬導電材料、摻雜質的半導 體材料、碳化物、導電氧化物或者·物製成。該導電體 的形狀可根據場發射電子源實際應用的產品而決定，如： 虽場發射電子源應用於平面顯示裝置時，陰極導電體可爲 平板狀結構；當場發射電子源應胳場發賴明燈管時， 陰極導電體可爲餘結構或絲狀結構；#場發射電子源應 用於場發射照龍泡時，陰極導電體可爲球狀結構。〜 奈米碳管漿料中主要包含有機载體以及分散於有機戴 體内的奈轉管’該奈祕的雜綠A致包 下步驟： 製備有機載體；該有機載體爲由作爲溶儀松油醇、 作爲增塑_少量鄰苯n 丁 |旨和作爲穩定劑的少量 乙基纖維素形成的混合劑；有機載體之製備過程爲：首先 200823949 於油浴加熱及授拌的條件下將乙基纖維素溶解到松油醇 中；加入鄰苯二甲酸二丁酯於同樣油浴加熱的條件下持續 攪拌一定時間即可得到有機載體。其中，優選地，松油醇、 乙基纖維素及鄰苯二曱酸二丁酯於混合劑中的質量百分比 分別約爲90%、5%以及5% ;加熱溫度爲80〜11(TC，最優地 加熱溫度爲100°c ;持續攪拌時間爲10〜25小時，最優地 持續攪拌時間爲24小時。 將粉末狀奈米碳管於二氯乙烷溶液中用破碎機分散後 ® 再進行超聲分散形成奈米碳管溶液；其中，奈米碳管可預 先通過化學氣相沈積法、電弧放電法或鐳射蒸發法等傳統 技術製備，奈米碳管的長度優選爲1〜100微米，直徑優選 爲1〜100納米。奈米碳管與二氯乙烷的比例優選爲：每兩 克奈米碳管需要約500毫升的二氯乙烷。破碎機分散的時 間優選爲5〜30分鐘’最優時間爲20分鐘；超聲分散的時 間優選爲10〜40分鐘，最優時間爲30分鐘。 • 過濾奈米碳管溶液；其中，奈米碳管溶液可選用篩網 過渡’最優地，選用400目的篩網過濾奈米碳管溶液從而 可得到具有優選直徑及長度的奈米碳管的溶液。 將奈米碳管溶液加入有機載體中同時亦利用超聲充分 分散；其中’溶液中的奈米碳管與有機載體的質量比優選 爲15 : 1 ;超聲分散的時間優選爲3〇分鐘。 最後’於水浴條件下加熱混有奈米碳管溶液的有機載 辦 一 ’二氣乙烷在加熱下完全蒸發；其中，加熱溫度優選爲 90°C。 11 200823949 另，導電漿料中含有一定量的玻璃微粒及導電金屬微 粒，其中，玻璃微粒選用溶點爲35〇〜_ ^直搜優選爲卟⑽納米。導電金屬微粒由導電材破料璃製 二如銀或乳化銦錫，其可預先採用球磨機進行球磨 徑優選爲〇. HG微米。導電漿料的形成係 及玻璃微粒於有機载體中進行充分混合而形成。According to the characteristics, the carbon nanotube material has the characteristics of high current density, extremely stable current and long service life, so it is widely used in microscopes, X-ray tubes, microwave tubes, CRT electron guns, solar energy conversion devices, lithographic printing devices, A transmitting end for field emission electron source in a device such as a flat display device. A conventional field emission electron source having a carbon nanotube as a emitting end generally includes at least a conductive substrate and a Vennike carbon official formed on the top of the conductive substrate as a emitting end. The method of forming a carbon nanotube on a conductive substrate mainly includes a mechanical method and an in-situ line method. In the towel, the mechanical method is to fix the synthesized carbon nanotubes by atomic force microscopy, and the synthesized carbon nanotubes are fixed on the conductive substrate with a conductive adhesive. The method is simple, but it is not easy to operate. The Neiwushi ruling system in the field emission electron source obtained by the method is coated with conductive adhesive on the φ too WHO & base body, and the contact state is poor during use, and it is difficult to fully exert the field of the Nike carbon officer. Launch performance. Dry Ding by the Γ Γ 线 line method _ prior to the conductive base rainbow metallization catalyst, after the dream by chemical vapor deposition, electric orphan discharge / after the error, the upper growth -_ tube = = method = /, the electrical contact of the electrical substrate is good. However, the field emission obtained by this method 8 200823949 shouted the carbon nanotubes to decompose the matrix's ability to bond (four), in use =, 'medium ~ + carbon tube material shedding, from the (four) to the field Wei electron source damage. The production cost of manufacturing a field emission electron source by in-situ growth is also high. In this case, it is indeed necessary to provide a low-cost, efficient and well-operated field emission electronic society manufacturing method, by which the carbon nanotubes in the electron source are tightly coupled with the conductive group. Electrical connection [The content of the invention] by the implementation of the ship-step detailed description - the method of the field emission electron source money 'this manufacturing method is low cost, ambiguous and has the same experience at the same time 'made by this method The carbon nanotubes in the electron-emitting source are tightly coupled and electrically connected to the V-electrode. A method for manufacturing a field emission electron source, the manufacturing method comprising the following steps: = at least - a cathode conductor, preparing a "light" and a conductive paste; ^ = coating a conductive paste on the pole conductor to conduct electricity _ Adding a conductive paste layer; 涂敷 coating a carbon nanotube charge on the conductive paste layer, heating the carbon nanotube material, forming a layer of the slurry layer from the secret layer; and forming The conductive (10) layer and the carbon nanotube slurry phase guide snow body are formed under the condition of ~·C to form a conductive layer and a carbon nanotube electron emission layer on the surface of the invisible secret guide, thereby obtaining a field emission electron source. Compared with the technology, the field emission electron source manufacturing method 9 200823949 of the present invention forms a conductive layer and a carbon nanotube electron emission layer by a two-layer slurry, which can be manufactured at a low cost and large area, and has high efficiency. At the same time, the field emission electron source manufactured by the method enables the conductive layer to be firmly bonded and electrically connected to the carbon nanotube electric f-emitting layer. [Embodiment] The field emission electron source of the present invention will be described below with reference to the accompanying drawings. Manufacturing method The method for manufacturing the field emission electron source of the present invention generally comprises the following steps: Step of providing at least a cathode conductor, preparing a certain amount of carbon nanotube slurry and a conductive paste. The cathode electrical conductor may be made of a metal conductive material, a doped semiconductor material, a carbide, a conductive oxide or a material. The shape of the electrical conductor may be determined according to the actual application of the field emission electron source, such as: When the electron source is applied to the flat display device, the cathode conductor may be a flat structure; when the field emission electron source should be applied to the lamp tube, the cathode conductor may be a residual structure or a filament structure; #field emission electron source is applied to the field When the illuminating bubble is emitted, the cathode conductor may have a spherical structure. ~ The carbon nanotube slurry mainly contains an organic carrier and a naphthalene tube dispersed in the organic wearing body. Step: preparing an organic carrier; the organic carrier is a mixture of a small amount of ethyl cellulose as a solvent, terpineol, as a plasticizer, a small amount of phthalic acid, and a stabilizer The preparation process of the organic carrier is as follows: firstly, the ethyl cellulose is dissolved in terpineol under the condition of heating and mixing in an oil bath; and the addition of dibutyl phthalate in the same oil bath is continued. The organic carrier can be obtained by stirring for a certain period of time. Among them, preferably, the mass percentages of terpineol, ethyl cellulose and dibutyl phthalate in the mixture are about 90%, 5% and 5%, respectively; The heating temperature is 80 to 11 (TC, the optimum heating temperature is 100 ° C; the continuous stirring time is 10 to 25 hours, and the optimum stirring time is 24 hours. The powdery carbon nanotubes are dichloroethane. The solution is dispersed in a crusher and then ultrasonically dispersed to form a carbon nanotube solution; wherein the carbon nanotubes can be prepared by conventional techniques such as chemical vapor deposition, arc discharge or laser evaporation, and the carbon nanotubes are prepared in advance. The length is preferably from 1 to 100 μm and the diameter is preferably from 1 to 100 nm. The ratio of carbon nanotubes to dichloroethane is preferably about 500 ml of dichloroethane per two grams of carbon nanotubes. The time during which the crusher is dispersed is preferably 5 to 30 minutes' optimal time is 20 minutes; the time for ultrasonic dispersion is preferably 10 to 40 minutes, and the optimum time is 30 minutes. • Filtering the carbon nanotube solution; wherein the carbon nanotube solution can be screened with a mesh transition. 'Optimally, a 400 mesh sieve is used to filter the carbon nanotube solution to obtain a carbon nanotube having a preferred diameter and length. Solution. The carbon nanotube solution is added to the organic vehicle while being sufficiently dispersed by ultrasound; wherein the mass ratio of the carbon nanotubes to the organic vehicle in the solution is preferably 15:1; the time of ultrasonic dispersion is preferably 3 minutes. Finally, the organic carrier-dioxane mixed with the carbon nanotube solution is heated under water bath conditions to completely evaporate under heating; wherein the heating temperature is preferably 90 °C. 11 200823949 In addition, the conductive paste contains a certain amount of glass particles and conductive metal particles, wherein the glass particles have a melting point of 35 〇 _ _ ^ directly searched preferably 卟 (10) nanometers. The conductive metal particles are made of a conductive material such as silver or emulsified indium tin, which may be ball milled in advance using a ball mill, preferably 〇. HG micron. The formation of the conductive paste and the formation of the glass fine particles in an organic vehicle are sufficiently mixed.
^要爲由作爲溶綱松油醇、作爲增關的少量鄰苯二甲 酸-丁 i旨及作爲敎_少量乙基纖維素形成的混合劑。 ，合過程優選爲60IC下混合3〜5小時。爲了更好的分 散導電金屬微粒及朗絲’可進—步使祕功率的超聲 波對含有導電金屬微粒及賴絲的有機輔進行超聲波 震蕩’後再對其進行離心處理。 步驟（二），於陰極導電體上塗敷導電聚料 料加熱形成-導·觸。 ^電水 其中，塗敷導電漿料的過程應於潔淨的環境内進行， 優選地，環境内的灰塵度小於1〇〇〇mg/m3。塗敷完成後，優 選用熱風將形成於陰極導電體上的導電漿料吹幹以形成導 電漿料層。該導電漿料層的厚度優選爲幾微米至幾十微米。 步驟（二）’於導電漿料層上塗敷奈米碳管漿料，將奈 米碳管漿料加熱從而於導電漿料層上形成一奈米碳管漿料 層0 塗敷奈米碳管漿料的過程亦應於潔淨的環境内進行， 優選地，環境内的灰塵度小於1000mg/m3。塗敷完成後，優 選用熱風將形成於導電漿料層上的奈米碳管聚料吹幹以形 12 200823949 成奈米碳管漿料層。 步驟（四）’將形成有導電漿料層及奈米碳管漿料層的 .導電體於餅下進行烘乾與域從而於導電體 .的表面上形成導電層及奈米碳管電子發射層，進而得到場 發射電子源。 每 其中，烘乾與焙燒於真空環境下進行或者於烘乾與焙 燒過程中通入惰性氣體或氮氣加以保護從而防止烘乾與= # 燒時發生氧化反應。烘乾之目的係在於使導電漿料層^ 米碳管漿料層中的有機載體從導電體上揮發。焙燒之目= 係在於使導電漿料層中的玻璃微粒熔融從而將導電金屬微 粒及奈米碳管粘結固定於導電體上從而形成導電層及奈米 碳管電子發射層，其中的奈米碳管通過導電金屬微粒二導 電體電性連接。另’溶融的玻璃可_整體的熱膨脹係數 防止所形成的導電層產生裂紋或發生斷裂。烘乾與焙燒之 過程可進-步包括：先於真空環境或通入情性氣體或氮氣 • 加以保護的環境下加熱至一定溫度保溫-段時間，優選加 熱至約32(TC Μ呆溫約20分鐘；後升溫至一定溫度再^ -段時間，優選升溫至約43(TC，保溫約3〇分鐘；最$ 至室溫。 爲進一步增強電子發射層的場發射特性，經過烘乾和 培燒過程後，可對電子發射層的表面進行摩擦或者採^膠 帶枯結的方法將電子發射層表面稀鬆的奈米碳管去除，剩 下的奈米碳管與導電金屬微粒及玻璃層結合牢固且與襯底 表面大致垂直（如圖2所示），該種稀疏且基本直立的奈= 13 200823949 碳管有效降低了奈米碳管之間的場屏蔽作用，從而使本實 施例的場發射電子源具備良好的場發射性能。 •在貝驗中對本實&例獲得的場發射電子源的場發射 /生貝進订了 Λ際測試。具體步驟為：於直徑約爲3⑼微米、 長度約爲10厘米的鎳絲表面形成奈米碳管電子發射層以 形成場發射電子源，將該場發射電子源置於内壁塗有透明 導電層及縣層且餘約爲25毫米、長度約爲1G厘米的 瞻纟璃g之轴心位置’測1得到的電壓—電流曲線圖如圖3 彳示從圖3中可以看出，於4⑽伏的電壓條件下，該場 發=電子源的電流爲190毫安培，對應的電流密度爲· 宅安培/平方厘米，因而本實施例得到的場發射電子源的場 發射性能較好。 综上所述，本發明確已符合發明專利之要件，遂依法 提出專利中請。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中請專利範圍。舉凡熟悉本案技藝 • j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】 圖1係本發明實施例場發射電子源之製造方法的流程 示意圖。 圖2係由本發明實施例場發射電子源之製造方法製得 的場發射電子源的掃描電鏡（Scanning 廿⑽It is intended to be a mixture of phthalic acid as a sulfonate, a small amount of phthalic acid as a weighting agent, and a small amount of ethyl cellulose. The mixing process is preferably mixed for 3 to 5 hours at 60 IC. In order to better disperse the conductive metal particles and the Langer's, the ultrasonic wave of the secret power can be ultrasonically oscillated to the organic auxiliary containing the conductive metal particles and the lysate, and then centrifuged. In step (2), a conductive poly-material is coated on the cathode electrical conductor to form a conductive-conductive contact. ^Electric water wherein the process of applying the conductive paste should be carried out in a clean environment, preferably, the degree of dust in the environment is less than 1 〇〇〇 mg/m3. After the coating is completed, the conductive paste formed on the cathode conductor is preferably blown dry by hot air to form a conductive paste layer. The thickness of the conductive paste layer is preferably from several micrometers to several tens of micrometers. Step (2) applying a carbon nanotube slurry on the conductive slurry layer, heating the nano carbon tube slurry to form a carbon nanotube slurry layer on the conductive paste layer 0 coating the carbon nanotube The process of the slurry should also be carried out in a clean environment. Preferably, the degree of dust in the environment is less than 1000 mg/m3. After the coating is completed, the carbon nanotubes formed on the conductive paste layer are preferably blown dry by hot air to form a layer of 200823949 carbon nanotube slurry. Step (4) 'The conductive body formed with the conductive paste layer and the carbon nanotube slurry layer is dried under the cake and the domain is formed to form a conductive layer on the surface of the conductor and the electron emission of the carbon nanotube The layer, in turn, obtains a field emission electron source. Each of the drying and baking is carried out in a vacuum environment or an inert gas or nitrogen is supplied during the drying and baking to protect the drying reaction from the drying reaction. The purpose of drying is to volatilize the organic vehicle in the layer of the conductive paste layer from the conductor. The purpose of roasting is to melt the glass particles in the conductive paste layer to bond the conductive metal particles and the carbon nanotubes to the conductor to form a conductive layer and a carbon nanotube electron-emitting layer, wherein the nano-particles are formed. The carbon tubes are electrically connected by the conductive metal particles and the two conductors. Further, the molten glass can have a thermal expansion coefficient as a whole to prevent cracking or cracking of the formed conductive layer. The drying and roasting process may include: heating in a vacuum environment or in a protected atmosphere or a nitrogen atmosphere to a certain temperature for a period of time, preferably to about 32 (TC Μ 温 temperature 20 minutes; after heating to a certain temperature for a further period of time, preferably to about 43 (TC, holding for about 3 〇 minutes; most to room temperature. To further enhance the field emission characteristics of the electron-emitting layer, after drying and cultivating After the burning process, the surface of the electron-emitting layer may be rubbed or the surface of the electron-emitting layer may be removed by a method of drying the tape, and the remaining carbon nanotubes are firmly bonded to the conductive metal particles and the glass layer. And substantially perpendicular to the surface of the substrate (as shown in Figure 2), the sparse and substantially upright n = 13 200823949 carbon tube effectively reduces the field shielding between the carbon nanotubes, thereby enabling the field emission of this embodiment The electron source has good field emission performance. • In the Bayesian test, the field emission/birth of the field emission electron source obtained by the real and the example was tested. The specific steps are: about 3 (9) micrometers in diameter and about the length. For 1 The surface of the 0 cm nickel wire forms a carbon nanotube electron emission layer to form a field emission electron source, and the field emission electron source is placed on the inner wall with a transparent conductive layer and a county layer with a balance of about 25 mm and a length of about 1 Gcm. The voltage-current curve obtained from the measurement of the axial position of the glazing g is shown in Fig. 3. It can be seen from Fig. 3 that at a voltage of 4 (10) volts, the current of the field = electron source is 190. Milliamperes, the corresponding current density is · ampere amperes per square centimeter, so the field emission electron source obtained in this embodiment has better field emission performance. In summary, the present invention has indeed met the requirements of the invention patent, and is proposed according to law. In the patent, please note that the above description is only a preferred embodiment of the present invention, and it is not possible to limit the scope of the patent in this case. Those skilled in the art will be equivalent to the spirit of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic flow chart of a method for fabricating a field emission electron source according to an embodiment of the present invention. FIG. 2 is a field emission electron source according to an embodiment of the present invention. Scanning electron microscope (Scanning 廿(10) for the field emission electron source produced by the manufacturing method
Microscope，SEM)照片。 圖3係由本發明實施例場發射電子源之製造方法製得 200823949 的場發射電子源於實際應用中測量得到的場發射性質曲線 圖。 .【主要元件符號說明】Microscope, SEM) photo. Fig. 3 is a graph showing the field emission properties measured by the field emission electron source of 200823949 produced by the field emission electron source of the embodiment of the present invention. [Main component symbol description]
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