TW200421387A - Field emission device - Google Patents

Abstract

The present invention provides a field-emission device employing carbon nanotubes. The device includes a cathode, a carbon nanotube array, the carbon nanotube array prepared by the Chemical Vapor Deposition Method has a top surface and a bottom portion. The top surface of the carbon nanotube array is electrically conductively connected with the cathode, and the bottom portion of the array is provided for emitting electrons. The nanotubes of the bottom of the carbon nanotube array are orderly arranged and aligned, and terminate at a common plane, accordingly, an improved field emission performance is desirably achieved.

Description

200421387200421387

【發明所屬之技術領域】 管之場發射元件。 【先前技術】 ,奈米碳管以其優良之導電性能、完美之晶格結構、奈 米尺度之尖端等特性成為優良之場發射陰極材料，具體參 見Walt A. de Heer 等人在Science 2 7 0， 1179-1180 0995), A Carbon Nanotube Field-Emission Electron Source —文。先前由美國專利第6, 232, 7〇6號揭示一種利 用奈米碳管場發射元件，該場發射元件I包括一基板，沈積 於基板上之催化劑，以及從催化劑上長出一束或多束相互 平行且垂直於基底之奈米碳管陣列。 奈米碳管之場發射特性在場發射平面顯示器件、電真 工叩件 大功率被波為件等領域具有廣闊之應用前景。 2〇〇1年3月7日公開之中國專利，，利用奈米碳管之場發射顯 二裝置及其製造方法，，，其申請號為〇 〇丨2丨丨4 〇，該專利揭 不利用奈米碳管作為場發射顯示中電子發射源，請參閱第 ^圖，在該專利中，奈米碳管9 〇用作發射尖端，其通過超 聲振動，外加電壓等方法喷射進細孔8 〇，故，無法確保該 奈米碳管9 0之高度及其頂部之平整性。 化學氣相沈積法（CVD)易於矽片、玻璃等基板上生長 出位置、取向、咼度均確定之奈米碳管陣列，具體參見范 守善等人Science 283， 512-514 (1999) ，Self-〇riented[Technical Field to which the Invention belongs] A field emission element of a tube. [Previous technology] Nano carbon tubes have become excellent field emission cathode materials due to their excellent electrical conductivity, perfect lattice structure, and nano-scale tips. For details, see Walt A. de Heer et al. In Science 2 7 0, 1179-1180 0995), A Carbon Nanotube Field-Emission Electron Source — text. A U.S. Patent No. 6,232,708 has previously disclosed a field emission element using a nano-carbon tube. The field emission element I includes a substrate, a catalyst deposited on the substrate, and a beam or more growing from the catalyst. Arrays of nano carbon tubes parallel to each other and perpendicular to the substrate. The field emission characteristics of nanometer carbon tubes have broad application prospects in fields such as field emission flat display devices, electro-technical components, and high-power passive components. The Chinese patent published on March 7, 2001, using nano carbon tube field emission display device and its manufacturing method, the application number is 〇〇 丨 2 丨 丨 4 〇 This patent is not disclosed Using a carbon nanotube as the electron emission source in the field emission display, please refer to Figure ^. In this patent, the carbon nanotube 90 is used as the emission tip, which is sprayed into the pores 8 by means of ultrasonic vibration, applied voltage, etc. 〇 Therefore, the height of the nano carbon tube 90 and the flatness of its top cannot be ensured. The chemical vapor deposition (CVD) method is easy to grow a carbon nanotube array with a determined position, orientation, and degree on substrates such as silicon wafers and glass. For details, see Fan Shoushan et al. Science 283, 512-514 (1999), Self- 〇riented

Regular Arrays of Carbon Nanotubes and Their FieldRegular Arrays of Carbon Nanotubes and Their Field

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200421387 五、發明說明（2)200421387 V. Description of Invention (2)

Emission Properties —文，點陣之尺寸可以通過半導體 一充―刻―工—曹—控制催彳L·劑薄膜達到很咼之精度。先 國專利第6，5 2 5，4 5 3號揭示一種利用薄膜電晶體（TF T )來控 制奈米碳管電子發射之場發射顯示器。 優化奈米碳管陣列之平面場發射性能必須採用三級型 結構，於該結構中為達到電子發射之均勻性，作為陰極之 奈米碳管陣列需要在大面積上確保微米量級之均句性。 然，CVD生長工藝要達到大面積均勻相當困難。如第九圖 所示之奈米碳管陣列掃描顯微（SEΜ )照片顯示，奈米碳 管陣列中每一束奈米碳管頂部均有彎曲，同一束内奈米碳 管之頂部也相當不平整，且該頂部表面夾雜有少量雜亂分 佈之催化劑顆粒及無定形碳等雜質，這些因素之存在將導 致場發射性能之不穩定及不均勻，影響奈米碳管陣列之場 發射性能。 有鑑於此，提供一種發射端奈米碳管陣列表面平整之 .奈米碳管場發射元件實為必要。 【發明内容】 本發明之目的在於提供一種發射端奈米碳管陣列表面 平整之奈米碳管場發射元件。 為實現上述發明目的，本發明採用之技術方案係提供 一種奈米碳管場發射元件，其包括一陰極，一奈米碳管陣 列，該奈米碳管陣列由CVD法製備而成且包括一頂部及一 生長根部，其中該陰極與該奈米碳管陣列頂部電連接、該 生長根部為場發射之電子發射端。Emission Properties—The size of the dot matrix can be controlled by the semiconductor charge-engraving-manufacturing-Cao-control agent to achieve very high precision. Prior Patent No. 6,5 2 5, 4 5 3 discloses a field emission display using a thin film transistor (TF T) to control the electron emission of a nano carbon tube. To optimize the planar field emission performance of a carbon nanotube array, a three-stage structure must be used. In this structure, in order to achieve the uniformity of electron emission, a carbon nanotube array as a cathode needs to ensure a uniform micron order on a large area. Sex. However, it is quite difficult to achieve a large area uniformity in the CVD growth process. As shown in the ninth carbon nanotube array scanning microscopy (SEM) photo, the tops of each carbon nanotube in the carbon nanotube array are curved, and the tops of the carbon nanotubes in the same bundle are also comparable. The surface is uneven, and a small amount of impurities such as scattered catalyst particles and amorphous carbon are mixed on the top surface. The existence of these factors will cause instability and non-uniformity of the field emission performance and affect the field emission performance of the carbon nanotube array. In view of this, it is necessary to provide a nanometer carbon tube field emission element with a flat surface at the emitting end. [Summary of the Invention] The object of the present invention is to provide a nano carbon tube field emission element with a flat nano carbon tube array surface at the emission end. In order to achieve the above-mentioned object of the invention, the technical solution adopted by the present invention is to provide a nano-carbon tube field emission element, which includes a cathode and a nano-carbon tube array. The nano-carbon tube array is prepared by a CVD method and includes a The top and a growth root, wherein the cathode is electrically connected to the top of the nano carbon tube array, and the growth root is a field emission electron emission terminal.

第6頁 200421387 五、發明說明（3) 場^發射元件之發射端表面參差 與先前技術中奈米碳營 二带會 碳管陣列發射端端部平整^ 降低奈米碳管場發射元件♦其南度在微米量級可控，極大 射元件之場發射性能。 笔子务射之不均勻性，提高場發 極5 0 實施方式】 請參閱第六圖··本發曰月 奈米碳管陣列4 〇 所揭示之場發射元件包括一陰 備而成，其包括一頂部42 该'奈米碳管陣列40由CVD法製 陰極5 0並與該陰極5 〇形成秦一生長根部4 4，該頂部4 2植入 奈米碳管陣列4 〇之生長:連接，該平整、整潔、有序之 露。 Μ 4作為場發射之電子發射端裸 本發明由以下步驟製 步驟1，請參閱第—肴而成。 工作模板1 0帶微小氣孔1 ^ ’首先提供一工作模板1 〇，該 中工作模板1 0易脫附。—’該微小氣孔1 2可確保後續工藝 微米以下，其材料為工作模板1 0表面平整度要求在1 度，本實施方式選用夕耐文70〇。C左右奈米碳管生長溫 步驟2，請參:第夕孔石夕作為工作細。。 隔離體2 0，本實施方吊圖’於工作模板1 0上製作一絕緣 之絕緣隔離體2 〇，該二彳木用鍍膜方式製作厚度為2 0 0微米 外、還可採用印刷g =緣隔離體20製作方法除鍍膜方式 之絕緣薄板則需要1直接採用現成之絕緣薄板，採用現成 米以下。此絕緣p雜=向工作模板1 0 一面之平整度在1微 ~ 2 〇之厚度根據奈米碳管陣列生長需 200421387 五、發明說明（4) ^ 要而定，其厚度範圍可為5微米〜1 0毫米，優選厚度範圍為 貧隔離體2 CT叉Γ材料應1夠n丁 奈米碳管生長溫度，可從下列材料中選取：耐溫玻璃、塗 敷絕緣層之金屬、矽、氧化矽、陶瓷或雲母。該絕緣隔離 體2 0之作用係提供奈米碳管生長之空間。 步驟3，請參閱第三圖，通過電子束蒸鍍法於工作模 板1 0上沈積一催化劑層3 0，沈積厚度為5奈米，一般要求 催化劑層沈積厚度為1〜1 0奈米，優選厚度為4〜6奈米。其 沈積方式除電子束蒸鍍法之外還可採用熱蒸鍍或者濺鍍 法，催化劑材料可為F e、C 〇、N i等過渡元素金屬或其合 金，本實施方式選用F e為催化劑。 步驟4，請參閱第四圖，將第三圖所示之催化劑層3 0 於2 0 0 ° C〜4 0 0 ° C之高溫下退火，使催化劑氧化、收縮成奈 米級催化劑顆粒（圖未示），再將工作模板1 0置於反應爐 (圖未示）中，於保護氣體氬氣存在下，通入碳源氣乙炔， 利用CVD法，於6 0 0〜7 0 0 ° C溫度下生長奈米碳管陣列40。通 常所生長奈米碳管陣列4 0之生長根部4 4之端面’（圖未示）與 絕緣隔離體2 0之上表面2 2基本位於同一平面。本實施方式 中所生長之奈米碳管陣列4 0之頂部4 2略高於絕緣隔離體2 0 之上表面2 2。 步驟5，請參閱第五圖，該奈米碳管陣列4 0之頂部4 2 平整度低、雜亂無序。於該頂部4 2沈積陰極5 0，沈積方法 可採用電子束蒸鍍法、熱蒸鍍法或濺鍍法等。該陰極5 0與 絕緣隔離體20之上表面22相連接。陰極50之材料可選用任Page 6 200421387 V. Description of the invention (3) The emission end surface of the field ^ emitting element is uneven compared with the emission end of the carbon tube array of the carbon nanotube band in the prior art. ^ Reduce the field emission element of the carbon nanotube Nandu is controllable on the order of micrometers, and its field emission performance is extremely large. Non-uniformity of pen-shot firing to improve field emission poles 50 Implementation Mode] Please refer to the sixth figure. The field emission element disclosed in this article is a nano-nano carbon tube array 4 〇 The field emission element includes a female preparation, which Including a top 42 the 'nano carbon tube array 40 is made by a CVD method of a cathode 50 and forms a Qin Yi growth root 44 with the cathode 50, the top 4 2 is implanted with a nano carbon tube array 40 growth: connection, The flat, neat and orderly dew. M 4 is used as a field-emitting electron-emitting terminal. The present invention is prepared by the following steps. The working template 10 is provided with a small air hole 1 ^ ′ First, a working template 10 is provided, and the working template 10 is easy to detach. —’The micro air holes 12 can ensure the subsequent process below micron, and the material is the working template 10. The surface flatness is required to be 1 degree. In this embodiment, Xenven 70 ° is used. The growth temperature of carbon nanotubes around C. Step 2. Please refer to: Di Xi Kong Shi Xi as work fine. . Isolator 20, this embodiment's drawing 'make an insulating insulator 2 0 on the work template 10, the linden wood is coated with a thickness of 200 micrometers and can be printed with g = edge In addition to the coating method for the insulation sheet of the isolation body 20, a ready-made insulation sheet is directly used, and the ready-made meter is used. The thickness of the insulating p impurity = the thickness of the flat surface of the working template 1 is between 1 micrometer and 2 micrometers. According to the growth requirements of the nano carbon tube array, 200421387 V. Description of the invention (4) ^ Depending on the thickness, the thickness range can be 5 microns ~ 10 mm, preferably in the range of lean insulator 2 CT fork Γ The material should be 1 n carbon nanotube growth temperature, which can be selected from the following materials: temperature-resistant glass, metal coated with insulation, silicon, oxidation Silicon, ceramic or mica. The role of the insulating spacer 20 is to provide a space for the growth of the carbon nanotubes. Step 3, referring to the third figure, a catalyst layer 30 is deposited on the working template 10 by the electron beam evaporation method, and the deposition thickness is 5 nanometers. Generally, the catalyst layer deposition thickness is 1 to 10 nanometers, preferably The thickness is 4 to 6 nanometers. In addition to the electron beam evaporation method, the deposition method may also adopt a thermal evaporation method or a sputtering method. The catalyst material may be a transition element metal such as Fe, Co, Ni, or an alloy thereof. In this embodiment, Fe is used as a catalyst. . Step 4, referring to the fourth figure, the catalyst layer 3 shown in the third figure is annealed at a high temperature of 200 ° C ~ 400 ° C to oxidize and shrink the catalyst into nano-sized catalyst particles (Figure (Not shown), and then place the working template 10 in a reaction furnace (not shown), in the presence of a protective gas argon, pass in a carbon source gas acetylene, and use CVD method at 60 0 ~ 7 0 0 ° C The carbon nanotube array 40 is grown at a temperature. The end surface '(not shown) of the growth root portion 4 4 of the generally grown carbon nanotube array 40 is substantially on the same plane as the upper surface 2 2 of the insulating spacer 20. The top 4 2 of the nano carbon tube array 40 grown in this embodiment is slightly higher than the upper surface 22 of the insulating spacer 2 0. Step 5, please refer to the fifth figure. The top 4 2 of the nano carbon tube array 40 has low flatness and disorder. A cathode 50 is deposited on the top 42. The deposition method can be an electron beam evaporation method, a thermal evaporation method, or a sputtering method. The cathode 50 is connected to the upper surface 22 of the insulating separator 20. The material of the cathode 50 is optional

第8頁 200421387 五、發明說明（5) 何金屬或合金。本實施方式採用電子束蒸鍍法，沈積金屬銅 =作-為陰1亟5 0，一玄—至凃米碳管陣列完 蓋。Page 8 200421387 V. Description of the invention (5) Any metal or alloy. This embodiment adopts the electron beam evaporation method, and deposits metallic copper = as-1 for Yin 1 and 50 for 1 xuan-until the rice-coated carbon tube array is completed.

步驟6，請參閱第六圖，將第五圖所示之結構翻轉， 並將工作模板1 〇去除，使奈米碳管陣列4 0之生長根部4 4完 全裸露，再通過物理方式或化學方式將奈米碳管陣列4 0之 生長根部4 4粘有之催化劑顆粒鐵去除，得到一平整、整 潔、有序之奈米碳管生長根部4 4，其平整性與工作模板1 0 之表面一致，平整度在1微米以下。該生長根部4 4作為場 發射之電子發射端，具有優良之均勻性I，且其均為開口。 請參閱第七圖，於絕緣隔離體2 0與陰極相對之表面 (圖未示）沈積一栅極6 0，該栅極6 0之沈積方式可採用電子 束蒸鍍法、熱蒸鍍法或濺鍍法等方式，其材料與陰極5 0之 要求相同，可選用任何金屬或合金。本實施方式選用電子 束蒸鍍沈積金屬銅製備栅極6 0。Step 6, referring to the sixth figure, flip the structure shown in the fifth figure, and remove the working template 10, so that the growth root 4 4 of the nano carbon tube array 40 is completely exposed, and then through physical or chemical methods The iron particles on the catalyst roots 4 4 of the nano carbon tube array 40 were removed to obtain a flat, neat and orderly nano carbon tube growth root 4 4. The flatness was consistent with the surface of the working template 10. The flatness is below 1 micron. The growing roots 44 serve as field emission electron-emitting ends, and have excellent uniformity I, and they are all open. Referring to the seventh figure, a grid 60 is deposited on the surface of the insulating separator 20 opposite to the cathode (not shown). The method of depositing the grid 60 can be electron beam evaporation, thermal evaporation, or The sputtering method and other methods have the same material requirements as the cathode 50. Any metal or alloy can be selected. In this embodiment, a metal copper is deposited by electron beam evaporation deposition to prepare the gate electrode 60.

本發明利用奈米碳管陣列4 0之生長根部4 4作為場發射 元件之電子發射端，相較先前場發射元件之奈米碳管陣列 4 0之頂部4 2作為場發射之電子發射端，奈米碳管陣列之生 長根部4 4相較頂部4 2更為平整、整潔、有序，可極大改善 奈米碳管陣列頂部4 2發射電子之不穩定性及不均勻性。 綜上所述，本發明確已符合發明專利要件，爰依法提 出專利申請。惟，以上所述者僅為本發明之較佳實施例， 舉凡熟悉本案技藝之人士，於援依本案發明精神所作之等 效修飾或變化，皆應包含於以下之申請專利範圍内。In the present invention, the growth root 44 of the nano-carbon tube array 40 is used as the electron emission terminal of the field emission element. Compared to the top 4 2 of the nano-carbon tube array 40 of the previous field emission element, it is used as the electron emission terminal of the field emission. The growth root 4 4 of the carbon nanotube array is flatter, cleaner and more ordered than the top 4 2, which can greatly improve the instability and non-uniformity of the electrons emitted from the top 4 2 of the carbon nanotube array. In summary, the present invention has indeed met the requirements for invention patents, and a patent application has been filed in accordance with the law. However, the above is only a preferred embodiment of the present invention. For those who are familiar with the skills of the present case, equivalent modifications or changes made in accordance with the spirit of the present invention should be included in the scope of patent application below.

200421387 圖式簡單說明 第 一 圖 係 本 發 明 多 孔 工 作 模 板 之 示 意 圖 〇 -— W -TLT 杈 袁 製 -— 緣 離 體 之 不 意 〇 第 '—- 圖 係 工 作 模 板 上 沈 積 催 化 劑 層 之 示 意 圖 〇 第 四 圖 係 催 化 劑 層 上 長 出 奈 米 碳 管 陣 列 之 示 意 圖 〇 第 五 圖 係 奈 米 碳 管 陣 列 之 頂 部 沈 積 有 陰 極 之 示 意 圖 〇 第 -i— /、 圖 係 第 五 圖 去 掉 工 作 模 板 後 之 場 發 射 元 件 示 意 圖 第 七 圖 係 第 /、 圖 所 示 發 射 元 件 之 絕 緣 隔 離 體 上 沈 積 極 之 示 意 圖 〇 第 八 圖 係 先 前 之 場 發 射 顯 示 裝 置 示 意 圖 〇 第 九 圖 係 奈 米 碳 管 陣 列 之 顯 微 眧 片 〇 主 要 元 件 符 號 說 明 ] 工 作 模 板 10 微 小 氣 孔 12 絕 緣 隔 離 體 20 絕 緣 隔 離 體 上 表 面 22 催 化 劑 層 30 奈 米 碳 管 陣 列 40 頂 部 42 生 長 *** 44 陰 極 50 柵 極 60200421387 Schematic illustration of the first diagram is the schematic diagram of the porous working template of the present invention 〇 --- W-TLT branch system-the unintentional relationship between the body and the body. The ―-‖ diagram is a schematic diagram of the catalyst layer deposited on the working template. Fourth Figure is a schematic diagram of a nano-carbon tube array grown on a catalyst layer. Figure 5 is a schematic diagram of a cathode deposited on the top of a nano-carbon tube array. Figure -i-/, Figure 5 is the field emission after removing the working template. Schematic diagram of the element. Figure 7 is a schematic diagram of the deposition electrode on the insulating insulator of the emitting element shown in Figures 8 and 8. The figure 8 is a schematic diagram of the previous field emission display device. The figure 9 is a micrograph of a nano carbon tube array. 〇Description of main component symbols] Working template 10 Micro air holes 12 Insulation insulator 20 Upper surface of insulation insulator 22 Chemical agent layer 30 nanometer carbon tube array 40 top part 42 growing root 44 cathode 50 grid electrode 60

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Claims (1)

200421387200421387 六、申請專利範圍 1. 一種場發射元件，其包括： 二一_ ---检極，及 _ ―― - -—_ = 一奈米碳管陣列，該奈米碳管陣列由化學氣相沈積法 製備而成，其包括一頂部及一生長根部， 其中該奈米碳管陣列頂部與該陰極電連接，該生長***作為場發射之電子發射端。 2. 如申請專利範圍第1項所述之場發射元件，其中 該奈米碳管陣列之生長根部平整度在1微米以下。6. Scope of Patent Application 1. A field emission element, which includes: two one _ --- detector, and _ -------_ = one nanometer carbon tube array, which is composed of chemical vapor phase It is prepared by a deposition method and includes a top and a growth root, wherein the top of the nano carbon tube array is electrically connected to the cathode, and the growth root is used as a field emission electron emission terminal. 2. The field emission element according to item 1 of the scope of patent application, wherein the growth root flatness of the nano carbon tube array is less than 1 micron. 3. 如申請專利範圍第1項所述之場發射元件，其中 該場發射元件進一步包括一絕緣隔離體，該絕緣隔離 體之一表面與該陰極相連。 4. 如申請專利範圍第3項所述之場發射元件，其中 該絕緣隔離體之製作方法包括鍍膜、印刷。 ，3. The field emission element according to item 1 of the scope of the patent application, wherein the field emission element further includes an insulating spacer, and one surface of the insulating spacer is connected to the cathode. 4. The field emission element as described in item 3 of the scope of patent application, wherein the manufacturing method of the insulating spacer includes coating and printing. , 5. 如申請專利範圍第3項所述之場發射元件，其中 該絕緣隔離體直接採用現成絕緣薄板。 6. 如申請專利範圍第3項所述之場發射元件，其中 該絕緣隔離體厚度為5微米〜1 0毫米。 7. 如申請專利範圍第3項所述之場發射元件，其中5. The field emission element as described in item 3 of the scope of patent application, wherein the insulating spacer is directly made of an existing insulating sheet. 6. The field emission element according to item 3 of the scope of patent application, wherein the thickness of the insulating spacer is 5 micrometers to 10 millimeters. 7. The field emission element as described in item 3 of the patent application scope, wherein 第11頁 200421387 六、申請專利範圍 該絕緣隔離體厚度範圍為1 0〜5 0 0微米。 8. 如申請專利範圍第3項所述之場發射元件，其中 該生長根部之端面與該絕緣隔離體靠近該陰極之表面 基本位於同一平面。 9. 如申請專利範圍第3項所述之場發射元件，其中 該絕緣隔離體之製作材料包括耐溫玻璃，塗敷絕緣層 之金屬、矽、氧化矽、陶瓷或雲母。 1 0.如申請專利範圍第3項所述之場發射元件，其中 該絕緣隔離體與該陰極相對之表面進一步包括一柵 極 ° 1 1.如申請專利範圍第1 0項所述之場發射元件，其中 該柵·極通過沈積方法沈積於該表面之上。 1 2.如申請專利範圍第1 0項所述之場發射元件，其中 該栅極之沈積方法包括電子束蒸鍍法、熱蒸鍍法或濺 鍍法。 1 3.如申請專利範圍第1項所述之場發射元件，其中 該奈米碳管陣列之生長根部均開口。Page 11 200421387 VI. Scope of patent application The thickness of this insulation insulator is 10 ~ 500 microns. 8. The field emission element according to item 3 of the scope of the patent application, wherein the end face of the growth root and the surface of the insulating separator near the cathode are substantially on the same plane. 9. The field emission element as described in item 3 of the scope of patent application, wherein the material of the insulating spacer includes temperature-resistant glass, metal coated with an insulating layer, silicon, silicon oxide, ceramic, or mica. 10. The field emission element as described in item 3 of the scope of patent application, wherein the surface of the insulating separator opposite to the cathode further comprises a grid ° 1 1. The field emission as described in item 10 of the scope of patent application An element, wherein the gate electrode is deposited on the surface by a deposition method. 1 2. The field emission element according to item 10 of the scope of the patent application, wherein the method of depositing the grid includes an electron beam evaporation method, a thermal evaporation method, or a sputtering method. 1 3. The field emission element according to item 1 of the scope of patent application, wherein the growth roots of the nano-carbon tube array are all open. 第12頁 200421387Page 12 200421387 第13頁Page 13