JP2014078494A - Method for manufacturing field emission electron source and method for manufacturing field emission electron source array - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a field emission electron source applied when an electron emitter is effectively fixed and electron emission efficiency is large, and a method for manufacturing a field emission electron source array.SOLUTION: A method for manufacturing a field emission electron source comprises: a first step of providing a carbon nanotube linear structure; a second step of covering a surface of the carbon nanotube linear structure with an insulating layer; a third step of forming a preliminary body of the field emission electron source by installing a plurality of conductive rings on the surface of the carbon nanotube linear structure at intervals; and a fourth step of forming a plurality of field emission electron sources by cutting the preliminary body of the field emission electron.

Description

  The present invention relates to a method for manufacturing a field emission electron source and a method for manufacturing a field emission electron source array.

  The field emission display device has superior display effects, wide viewing angle, low power consumption, downsizing, and the like compared to a cathode ray tube (CRT) display device and a liquid crystal display device (LCD). In particular, field emission display devices (CNT-FED) using carbon nanotubes are currently attracting attention as display devices. Carbon Nanotube (CNT) is a new type of carbon material and was discovered in 1991 by Japanese researcher Sumio Iijima (see Non-Patent Document 1). Carbon nanotubes have good conductivity performance, good chemical stability, large aspect ratio (ratio of length to diameter), and the tip area reaches the theoretically best dimension, so the smaller the tip area, Carbon nanotubes are currently one of the best electron emitters for field emission displays due to the theory of local electric field concentration.

  A field emission electron source is an important element of a field emission display. A conventional method of manufacturing a field emission electron source includes providing a substrate, placing an insulating layer on the surface of the substrate, etching the insulating layer to expose a part of the surface of the substrate, Forming a plurality of cathode electrodes, and placing a carbon nanotube on the plurality of cathode electrodes by chemical vapor deposition to form an electron emitter.

  However, in the method for manufacturing a field emission electron source, since carbon nanotubes as electron emitters are grown directly on the cathode electrode, the adhesion of the carbon nanotubes to the cathode electrode is weak. Thereby, when the electron emission efficiency of the field emission electron source is large, the carbon nanotube is easily separated from the cathode electrode by the strong electric field. As a result, the electron emission capability of the field emission electron source is reduced, the stability is deteriorated, and the service life is shortened.

Sumio Iijima, “Helical Microtubules of Graphic Carbon”, Nature, November 7, 1991, vol. 354, p. 56-58

  Therefore, in order to solve the above-mentioned problems, a method for manufacturing a field emission electron source and a method for manufacturing a field emission electron source array, which are applied when the electron emitter is effectively fixed and the electron emission efficiency is high, are provided.

  The method of manufacturing a field emission electron source according to the present invention includes a first step of providing a carbon nanotube linear structure, a second step of covering an insulating layer on a surface of the carbon nanotube linear structure, A plurality of conductive rings are installed on the surface at intervals, and a third step of forming a preliminary body of the field emission electron source and a preliminary body of the field emission electron source are cut to form a plurality of field emission electron sources. And at least one end of each of the field emission electron sources is provided with at least one conductive ring, and from the cut surface obtained by cutting the preliminary body of the field emission electron source, The conductive ring, the insulating layer, and the carbon nanotube linear structure are exposed and located on the same plane.

  The method of manufacturing a field emission electron source array according to the present invention includes a first step of providing a carbon nanotube linear structure, a second step of covering the surface of the carbon nanotube linear structure with an insulating layer, and the insulating layer. A plurality of conductive rings are provided on the surface of the conductive ring at a distance to form a preliminary body of the field emission electron source, and a plurality of preliminary bodies of the field emission electron source are installed in parallel, and the adjacent conductive rings A fourth step of forming a field emission electron source array preliminary body, and a fifth step of cutting the field emission electron source array preliminary body to form a plurality of field emission electron source arrays. The conductive ring, the insulating layer, and the carbon nanotube linear structure are exposed from a cut surface obtained by cutting the field emission electron source array preliminary body, and are located on the same plane. .

  The method of manufacturing a field emission electron source of the present invention includes a first step of providing a carbon nanotube linear structure, a second step of covering the surface of the carbon nanotube linear structure with an insulating material, A third step of installing a plurality of conductive rings on the surface at intervals, wherein the conductive ring has two surfaces facing each other; and a plurality of conductive rings coated with the insulating material A fourth step of cutting the carbon nanotube linear structure in which a plurality of field emission elements are cut along one surface of the conductive ring or from a position between the two surfaces of the conductive ring. The fourth step of forming the electron source preliminary body and the insulating material in the plurality of field emission electron source preliminary bodies are sintered to form the insulating layer, thereby forming the plurality of field emission electron sources. And at least one conductive ring is disposed at at least one end of each of the field emission electron sources, and an end of the carbon nanotube linear structure is exposed without being covered with an insulating layer. .

  Compared with the prior art, in the method of manufacturing the field emission electron source and the method of manufacturing the field emission electron source array of the present invention, the surface of the carbon nanotube linear structure is coated with an insulating layer, so that the carbon nanotube linear The structure is firmly fixed to the insulating layer, and the insulating layer gives a fixing force to the carbon nanotube linear structure. Accordingly, even when the electron emission efficiency of the field emission electron source is large, the carbon nanotubes are not easily separated from the cathode electrode by the strong electric field, thereby increasing the electron emission capability of the field emission electron source. The service life can be extended.

It is process drawing of the manufacturing method of the field emission electron source which concerns on Example 1 of this invention. It is a scanning electron micrograph of the non-twisted carbon nanotube wire in Example 1 of this invention. It is a scanning electron micrograph of the twist carbon nanotube wire in Example 1 of this invention. FIG. 6 is a structural diagram of a field emission electron source according to Example 2 of the present invention. FIG. 6 is a structural diagram of a field emission display device according to Example 3 of the present invention. It is process drawing of the manufacturing method of the field emission electron source which concerns on Example 4 of this invention. It is structural sectional drawing of the field emission electron source which concerns on Example 5 of this invention. It is process drawing of the manufacturing method of the field emission electron source which concerns on Example 6 of this invention. It is process drawing of the manufacturing method of the field emission electron source array which concerns on Example 7 of this invention. FIG. 10 is a structural diagram when the surface of the field emission electron source array obtained by the method of manufacturing the field emission electron source array of FIG. 9 is coated with a conductive layer. FIG. 10 is a structural diagram of a field emission display device according to Example 8 of the present invention; It is process drawing of the manufacturing method of the field emission electron source array which concerns on Example 9 of this invention.

  Embodiments of the present invention will be described below with reference to the drawings. And in the following each Example, the same member is labeled with the same code | symbol.

Example 1
Referring to FIG. 1, Embodiment 1 of the present invention provides a method for manufacturing a field emission electron source 10. The method of manufacturing the field emission electron source 10 includes the step of providing the carbon nanotube linear structure 110 (S10), the step of covering the surface of the carbon nanotube linear structure 110 with the insulating layer 120 (S11), and the insulating layer. A plurality of conductive rings 130 are installed on the surface of 120 at intervals to form a field emission electron source preliminary body 112 (S12), and the field emission electron source preliminary body 112 is cut to form a plurality of electric fields. A step (S13) in which the emission electron source 10 is formed, and at least one of the formed field emission electron sources 10 is provided with the at least one conductive ring.

  In step (S10), the carbon nanotube linear structure 110 is a free-standing structure and has flexibility, so that it can be used as a linear electron emitter. The carbon nanotube linear structure 110 is a linear structure including carbon nanotubes. The carbon nanotube linear structure 110 includes at least one carbon nanotube, at least one carbon nanotube wire, at least one composite carbon nanotube wire, or a combination thereof. Examples of the combination method include a combination of a carbon nanotube wire and a carbon nanotube, or a combination of a carbon nanotube wire and a composite carbon nanotube wire. The one carbon nanotube is one single-walled carbon nanotube or one multi-walled carbon nanotube. The carbon nanotube wire is a linear structure formed by arranging a plurality of carbon nanotubes in parallel, or a linear structure formed by twisting a plurality of carbon nanotubes. A composite carbon nanotube wire is a linear structure formed of a carbon nanotube wire and an organic material or an inorganic material. Further, the carbon nanotube linear structure 110 may include at least a support line. The support line has flexibility and plasticity, and the support line is closely and parallel to the carbon nanotube, carbon nanotube wire or composite carbon nanotube wire, or the support line is the carbon nanotube, carbon nanotube wire or composite Twisted with carbon nanotube wire. The support wire may be a metal wire such as an iron wire, an aluminum wire, a copper wire, a gold wire, a molybdenum wire or a silver wire, or another non-metallic material. Since the support line can provide mechanical support, the supportability of the carbon nanotube linear structure 110 can be ensured. The diameter and length of the support line can be selected as required. The diameter of the support wire is 50 μm to 500 μm, and the self-standing structure of the carbon nanotube linear structure 110 can be enhanced. The carbon nanotube linear structure 110 has a diameter of 0.5 nm to 600 μm. Preferably, the carbon nanotube linear structure 110 is made of only carbon nanotubes, and the diameter thereof is 0.01 μm to 10 μm.

  The carbon nanotube linear structure 110 is preferably made of a carbon nanotube wire, and the carbon nanotube wire is a self-supporting structure. Here, the self-supporting structure is a form in which a carbon nanotube wire can be used independently without using a support material. The carbon nanotube linear structure 110 includes at least one carbon nanotube wire. When the carbon nanotube linear structure 110 includes a plurality of carbon nanotube wires, the plurality of carbon nanotube wires are arranged in parallel to form an untwisted carbon nanotube structure, or the plurality of carbon nanotube wires are twisted with respect to each other. To form a twisted carbon nanotube structure. The diameter of the carbon nanotube linear structure 110 made of carbon nanotube wires is 0.03 μm to 5 μm. In this embodiment, the carbon nanotube linear structure 110 is composed of three carbon nanotube wires, and the three carbon nanotube wires are in contact with each other and arranged in parallel to each other. The diameter of the carbon nanotube linear structure 110 is 0.05 μm.

  As shown in FIGS. 2 and 3, the carbon nanotube wire is a non-twisted carbon nanotube wire or a twisted carbon nanotube wire. The non-twisted carbon nanotube wire is composed of a plurality of carbon nanotubes connected by intermolecular force. The plurality of carbon nanotubes are arranged in parallel to the central axis of the carbon nanotube wire. That is, the axial direction of the carbon nanotube is basically parallel to the axial direction of the carbon nanotube wire. The twisted carbon nanotube wire is also composed of a plurality of carbon nanotubes. The axial directions of the plurality of carbon nanotubes are arranged in a spiral along the axial direction of the carbon nanotube wires. In the carbon nanotube wire, adjacent carbon nanotubes are connected to each other in the drawing direction by intermolecular force. The diameter of the carbon nanotube wire is not limited, and is 0.5 nm to 100 μm. The carbon nanotube in the carbon nanotube wire is one of single-walled carbon nanotube, double-walled carbon nanotube, and multi-walled carbon nanotube. The diameter of the carbon nanotube is smaller than 5 nm, and the length of the carbon nanotube is 10 μm to 100 μm.

  The method of manufacturing a carbon nanotube wire includes a step of providing a carbon nanotube array (S101), a step of pulling out the carbon nanotube array by a tool to obtain an oriented carbon nanotube structure (S102), and processing the oriented carbon nanotube structure Forming a carbon nanotube wire (S103).

  In the step (S101), the carbon nanotube array is preferably a super-aligned array of carbon nanotubes. The carbon nanotube array is any one or a combination of a single-walled carbon nanotube array, a double-walled carbon nanotube array, and a multi-walled carbon nanotube array. In the present embodiment, a chemical vapor deposition method is employed as a method for manufacturing the super aligned carbon nanotube array. The manufacturing method of the super aligned carbon nanotube array includes the following steps.

  In step (a), a flat substrate is provided. The substrate is one of a p-type silicon substrate, an n-type silicon substrate, and a silicon substrate on which an oxide layer is formed. In this embodiment, it is preferable to select a 4-inch silicon substrate. In step (b), a catalyst layer is uniformly formed on the surface of the substrate. The material of the catalyst layer is any one of iron, cobalt, nickel and two or more kinds of these alloys. In step (c), the substrate on which the catalyst layer has been formed is annealed with air at 700 to 900 ° C. for 30 to 90 minutes. In step (d), the annealed substrate is placed in a reaction furnace, heated at a temperature of 500 ° C. to 740 ° C. with a protective gas, then introduced with a gas containing carbon, reacted for 5 to 30 minutes, and super-arrayed A carbon nanotube array (Superaligned array of carbon nanotubes) is grown. The height at which this carbon nanotube array grows is 200 μm to 400 μm. The carbon nanotube array is composed of a plurality of carbon nanotubes that grow parallel to each other and perpendicular to the substrate. Since the carbon nanotubes are long, the carbon nanotubes are partially entangled with each other. By controlling the growth conditions, the carbon nanotube array does not contain impurities such as amorphous carbon and remaining metal particles as a catalyst. The carbon nanotubes in the super-aligned carbon nanotube array are in close contact with each other by intermolecular force to form an array. The area of the super aligned carbon nanotube array is basically the same as the area of the substrate.

  In this embodiment, as the gas containing carbon, for example, active hydrocarbons such as acetylene, ethylene, and methane can be selected, but ethylene is preferably selected. The protective gas is nitrogen gas or inert gas, but is preferably argon gas.

  In step (S102), the method for manufacturing the carbon nanotube structure includes the following steps. In step (a), a tool such as tweezers is used to have a plurality of carbon nanotube ends. Or it has the edge part of a some carbon nanotube using the tape which has a fixed width | variety. In step (b), the plurality of carbon nanotubes are pulled out at a predetermined speed to form a continuous oriented carbon nanotube structure composed of a plurality of carbon nanotube segments.

  In the step of pulling out the plurality of carbon nanotubes, when the plurality of carbon nanotubes are detached from the substrate, the carbon nanotube segments are joined to each other by an intermolecular force, and a continuous oriented carbon nanotube structure is obtained. Is formed. In the oriented carbon nanotube structure, the arrangement direction of the carbon nanotubes is basically parallel to the direction of drawing out the carbon nanotubes.

  The oriented carbon nanotube structure is a carbon nanotube film or a carbon nanotube wire. The carbon nanotube film and the carbon nanotube wire are preferably made of only carbon nanotubes. When the width of the plurality of carbon nanotube segments is large, the obtained oriented carbon nanotube structure is a carbon nanotube film. When the width of the plurality of carbon nanotube segments is small, the obtained oriented carbon nanotube structure is a carbon nanotube wire.

  In the step (S103), when the oriented carbon nanotube structure is a wide carbon nanotube film, there are the following three methods for forming the carbon nanotube wire. In the first type, the carbon nanotube film is cut with a predetermined width along the longitudinal direction of the carbon nanotube in the carbon nanotube film to form a non-twisted carbon nanotube wire. In the second type, the carbon nanotube film is immersed in an organic solvent, and the carbon nanotube film is contracted to form a non-twisted carbon nanotube wire. In the third type, a carbon nanotube film is machined (for example, spun) to form a twisted carbon nanotube wire. Specifically, first, the carbon nanotube film is fixed to the spinning device. Next, the spinning device is operated to rotate the carbon nanotube film to form a twisted carbon nanotube wire. Alternatively, a stretching tool installed at one end of the carbon nanotube film is fixed to a rotating electric machine, and the carbon nanotube film is twisted to form a twisted carbon nanotube wire.

  In step (S11), the insulating layer 120 is formed on the entire outer surface of the carbon nanotube linear structure 110 by a coating method, a vapor deposition method, an electron sputtering method, or an ion sputtering method. Thereby, the insulating layer 120 is coated on the outer surface of the carbon nanotube linear structure 110. Here, the fact that the insulating layer 120 is formed on the entire outer surface of the carbon nanotube linear structure 110 means that the insulating layer 120 is formed on the entire outer surface excluding both end points of the carbon nanotube linear structure 110. That the surface of the carbon nanotube linear structure 110 is covered means that the entire surface of the carbon nanotube linear structure 110 is continuously covered with the insulating layer 120, and the insulating layer 120 and the carbon nanotube linear structure 110 are covered. Refers to the surface being affixed and in direct close contact. The thickness of the insulating layer 120 is 1 μm to 10 μm. After the insulating layer 120 covers the surface of the carbon nanotube linear structure 110, the shape of the cross section formed by the carbon nanotube linear structure 110 and the insulating layer 120 is any one of a circle, a square, a triangle, a rectangle, etc. Other shapes. In this embodiment, the thickness of the insulating layer 120 is 3 μm.

  In the step of forming the insulating layer 120, the insulating material and the carbon nanotube linear structure 110 are closely bonded by an intermolecular adsorption action. Thereby, the insulating layer 120 is stuck on the surface of the carbon nanotube linear structure 110, and the carbon nanotube linear structure 110 is firmly fixed to the insulating layer 120. Furthermore, since the surface of the carbon nanotube linear structure 110 has a plurality of gaps, a part of the insulating material of the insulating layer 120 penetrates into the gap, so that the insulating layer 120 and the carbon nanotube linear structure 110 are separated from each other. Can be tightly coupled. Thereby, the mechanical strength of the carbon nanotube linear structure 110 can be increased.

The insulating layer 120 is used for electrical insulation. The material of the insulating layer 120 is any one of vacuum ceramics (main components are Al ₂ O ₃ and Mg ₂ SiO ₄ ), aluminum oxide, Teflon (registered trademark), and nano clay-polymer composite material. Nanoclay in a nanoclay-polymer composite is a nano-sized layered silicate mineral, polyhydrated silicate and a certain amount of aluminum oxide, alkali metal oxide and alkaline earth metal. Made of oxide. The nano clay is excellent in fire resistance. The nano clay is, for example, nano-kaolin or nano-montmorillonite. Examples of the polymer material include silicon resin, polyamide, and polyolefin (for example, polyethylene and polypropylene). In this embodiment, the material of the insulating layer 120 is a vacuum ceramic. Since the vacuum ceramic has excellent electrical insulation and fire resistance, it can provide electrical insulation to the carbon nanotube linear structure 110 and protect the carbon nanotube linear structure 110.

  Further, the insulating layer 120 may be discontinuously coated on the outer surface of the carbon nanotube linear structure 110 at intervals, and it is only necessary to ensure that the conductive ring 130 can be formed on the surface of the insulating layer 120. .

  In the present embodiment, the method for manufacturing the insulating layer 120 includes a step of coating an insulating material on the surface of the carbon nanotube linear structure 110 (S111), and a step of sintering the coated insulating material (S112). Including.

  In step (S112), the gas in the insulating material can be eliminated through the step of sintering the insulating material. Thereby, in the process of operating the field emission electron source 10, no gas is generated from the insulating material, so that the field emission capability of the carbon nanotube linear structure 110 is not affected, and the insulating layer 120 and the carbon nanotube linear structure are not affected. The bond strength of 110 can be increased.

  In step (S12), a plurality of conductive rings 130 are installed on the surface of the insulating layer 120 at intervals. That is, the plurality of conductive rings 130 are installed at regular intervals along the direction of the central axis of the carbon nanotube linear structure 110. The distance between two adjacent conductive rings 130 may or may not be the same. The distance between two adjacent conductive rings 130 is preferably the same. Thereby, field emission electron sources having the same length can be formed, and uniform field emission can be realized. The conductive ring 130 is a ring-shaped structure, and surrounds the insulating layer 120 and is attached to the surface of the insulating layer 120. The conductive ring 130 may be a sealed ring-shaped structure or a semi-sealed ring-shaped structure. The conductive ring 130 has two opposite surfaces in the extending direction of its central axis. Here, the two surfaces are defined as a first surface and a second surface. The first surface and the second surface are perpendicular to the central axis of the carbon nanotube linear structure 110. Alternatively, the first surface and the second surface form a specific angle with the central axis of the carbon nanotube linear structure 110.

  The width of the conductive ring 130 refers to the length extending along the central axis of the carbon nanotube linear structure 110. The said width | variety is 1 micrometer-20 micrometers, and can be selected as needed. The surface of the carbon nanotube linear structure 110 is uniformly coated with the conductive ring 130. That is, the thickness of the conductive ring 130 at each position is the same. This thickness of the conductive ring 130 refers to the difference between the outer diameter and the inner diameter of the conductive ring 130. The thickness of the conductive ring 130 is 1 μm to 10 μm. The material of the conductive ring 130 is a metal having excellent conductivity, for example, one of copper, silver, gold, or an alloy thereof. The grains of material forming the conductive ring 130 are at the nano level, and preferably the grain diameter is less than 100 nm. This ensures that the conductive ring 130 is essentially free of gas and reduces the residual gas from affecting field emission. In this embodiment, the first surface and the second surface of the conductive ring 130 are perpendicular to the central axis of the carbon nanotube linear structure 110, and the material of the conductive ring 130 is silver. The width of the conductive ring 130 is 4 μm and the thickness is 2 μm. In this embodiment, the conductive ring 130 is formed by physical vapor deposition (PVD) (for example, vacuum deposition, ion sputtering, or electrochemical plating). Preferably, mask vacuum deposition is used. To form a conductive ring 130. The distance between two adjacent conductive rings 130 is 4 μm to 20 μm, for example, 6 μm, 10 μm, 15 μm, etc. Depending on the height of the field emission electron source 10 to be formed. The distance between two adjacent conductive rings 130 can be selected.

  In step (S13), the method of forming a plurality of field emission electron sources 10 fixes both ends of the field emission electron source spare 112 and forms a plurality of conductive rings 130 on the field emission electron source reserve 112. Cutting the field emission electron source preliminary body 112 to form a plurality of field emission electron sources 10 and covering the conductive ring 130 with at least one end of the field emission electron source 10 (S132); including.

  In step (S132), as long as it is ensured that the conductive ring 130 covers at least one end of the field emission electron source 10, a method for cutting the preliminary body 112 of the field emission electron source can be selected as necessary. For example, the conductive ring 130 is cut from a position where the first surface and the second surface of the conductive ring 130 are in contact with the insulating layer 120. Alternatively, it can be cut from an arbitrary position of the conductive ring 130 between the first surface and the second surface. Specifically, for example, the Nth conductive ring 130 is cut from a position where the first surface is in contact with the insulating layer 120 or an arbitrary position of the conductive ring 130 between the first surface and the second surface. In the case of the adjacent N + 1th conductive ring 130, the position where the first surface is in contact with the insulating layer 120, the position where the second surface is in contact with the insulating layer 120, and between the first surface and the second surface It can be cut at any position of the conductive ring 130 or from the surface of the preliminary field 112 of the field emission electron source between the Nth conductive ring 130 and the (N + 1) th conductive ring 130. When the second surface is cut from the position where the second surface contacts the insulating layer 120 with respect to the Nth conductive ring 130, the conductivity between the first surface and the second surface with respect to the (N + 1) th conductive ring 130. The ring 130 can be cut from an arbitrary position or a position where the second surface contacts the insulating layer 120. The order of cutting is not limited, and the cutting may be performed simultaneously or may be performed in order.

After cutting the field emission electron source reserve 112, a flat cross-section is formed. At least one end of the field emission electron source 10 is covered with a conductive ring 130. The carbon nanotubes in the carbon nanotube linear structure 110 are exposed from this flat cross section and serve as electron emission ends. The direction in which the preliminary body 112 of the field emission electron source is cut forms an angle α with the extending direction of the carbon nanotube linear structure 110. The angle α is 0 ° to 90 ° (not including 0 °). Preferably, the angle α is 90 °. That is, the direction of cutting the preliminary body 112 of the field emission electron source is perpendicular to the extending direction of the carbon nanotube linear structure 110. In the present embodiment, the conductive ring 130, the insulating layer 120, and the carbon nanotube linear structure 110 are cut from an arbitrary position of the conductive ring 130 between the first surface and the second surface, so that a plurality of field emission electron sources 10 are obtained. Form. At this time, the conductive rings 130 are installed at both ends of the field emission electron source 10. The preliminary body 112 of the field emission electron source is cut by a physical cutting method or a chemical cutting method (for example, a mechanical cutting method or a laser cutting method (CO ₂ or Nd: YAG laser)). In the present embodiment, the preliminary body 112 of the field emission electron source is cut by a mechanical cutting method.

  In order to ensure that the structure of the field emission electron source 10 is formed in the cutting step, both ends of the preliminary body 112 of the field emission electron source are fixed. Further, step S131 can be omitted as necessary.

(Example 2)
Referring to FIG. 4, the second embodiment of the present invention provides a field emission electron source 10. The field emission electron source 10 includes a carbon nanotube linear structure 110, an insulating layer 120, and a conductive ring 130. The surface of the carbon nanotube linear structure 110 is covered with an insulating layer 120. At least one conductive ring 130 is installed on at least one end of the carbon nanotube linear structure 110 covered with the insulating layer 120. The carbon nanotube linear structure 110, the insulating layer 120, and the conductive ring 130 are installed on the same axis. The carbon nanotube linear structure 110 is exposed from both ends of the field emission electron source 10. Here, the end of the carbon nanotube linear structure 110 exposed from both ends of the field emission electron source 10 is defined as the end of the carbon nanotube linear structure 110. At one end of the field emission electron source 10, the surface of the conductive ring 130 adjacent to the end of the carbon nanotube linear structure 110, the end of the carbon nanotube linear structure 110, and the surface from which the insulating layer 120 is cut are: Located on the same flat horizontal plane.

  The carbon nanotube linear structure 110 is a linear structure including carbon nanotubes. The carbon nanotube linear structure 110 includes at least one carbon nanotube, at least one carbon nanotube wire, at least one composite carbon nanotube wire, or a combination thereof. When the carbon nanotube linear structure 110 includes a plurality of carbon nanotubes, the plurality of carbon nanotubes are arranged in parallel to form a linear structure, or twisted together to form a linear structure. Similarly, when the carbon nanotube linear structure 110 includes a plurality of carbon nanotube wires, a plurality of carbon nanotube wires are arranged in parallel to form a linear structure, or the linear structures are twisted with respect to each other. Form. Similarly, when the carbon nanotube linear structure 110 includes a plurality of composite carbon nanotube wires, the carbon nanotube wires and the silicon nanotubes are arranged in parallel to form a linear structure or are twisted together to form a linear structure. Form the body.

  The insulating layer 120 is coated on the surface of the carbon nanotube linear structure 110 and is in direct contact with the surface of the carbon nanotube linear structure 110. Furthermore, since the surface of the carbon nanotube linear structure 110 has a plurality of gaps, a part of the insulating layer 120 can enter the gap on the surface of the carbon nanotube linear structure 110. Thereby, the insulating layer 120 can be tightly coupled to the carbon nanotube linear structure 110, and the mechanical strength of the carbon nanotube linear structure 110 can be increased. The thickness of the insulating layer 120 can be selected as necessary. For example, the thickness of the insulating layer 120 is selected according to the voltage applied between the conductive ring 130 and the carbon nanotube linear structure 110. Thereby, electron emission performance can be improved. Preferably, the insulating layer 120 has a thickness of 1 μm to 10 μm. In this embodiment, the thickness of the insulating layer 120 is 3 μm. Two ends of the carbon nanotube linear structure 110 are exposed from the insulating layer 120.

  At least one conductive ring 130 is installed on at least one end of the field emission electron source 10. The conductive ring 130 is installed on the surface of the insulating layer 120 and insulated from the carbon nanotube linear structure 110. The conductive ring 130 is a ring-shaped structure and has two opposite surfaces in the extending direction of the central axis. The conductive ring 130, the insulating layer 120, and the carbon nanotube linear structure 110 are installed on the same axis. The conductive ring 130 may be a sealed ring structure or an unsealed ring structure. By applying a voltage between the conductive ring 130 and the carbon nanotube linear structure 110, electron emission of the carbon nanotube linear structure 110 is realized. The thickness of the conductive ring 130 is not limited and can be selected according to the voltage to be applied. When two conductive rings 130 are installed at both ends of the field emission electron source 10, one conductive ring 130 provides an anode voltage, and the other one conductive ring 130 is welded, whereby the field emission electron source is provided. 10 is fixed to the cathode of the external electric circuit. Accordingly, the carbon nanotube linear structure 110 is in close contact with the cathode to reduce the gap. Further, the heat generated in the step of emitting electrons is reduced, and the service life of the field emission electron source 10 is extended.

  By applying an anode voltage to the conductive ring 130 at one end of the field emission electron source 10 and applying a cathode voltage to the conductive ring 130 at the other end of the field emission electron source 10, the conductive ring 130 and the carbon nanotube linear structure are applied. A voltage is generated during 110. The voltage drives the carbon nanotubes in the carbon nanotube linear structure 110 to emit electrons. In this embodiment, the thickness of the conductive ring 130 is 2 μm, the voltage formed between the conductive ring 130 and the carbon nanotube linear structure 110 is 3V to 6V, and the conductive ring 130 and the carbon nanotube linear structure are The electric field strength formed between the body 110 is 1 to 2 V / μm. Under the above conditions, the carbon nanotubes in the carbon nanotube linear structure 110 can emit electrons and at the same time, the driving voltage can be lowered. Thereby, defective phenomena such as puncture under a high voltage can be prevented, and the service life of the field emission electron source 10 can be extended.

  The field emission electron source 10 and the manufacturing method thereof of the present invention have the following excellent effects. First, since the carbon nanotube linear structure 110 is directly fixed to the insulating layer 120 and is tightly coupled to the insulating layer 120, the carbon nanotube linear structure 110 is prevented from being separated from the insulating layer 120. it can. Thereby, when the electron emission efficiency of the field emission electron source 10 is large, the carbon nanotubes in the carbon nanotube linear structure 110 are not easily separated from the cathode electrode by the strong electric field. Secondly, since each field emission electron source 10 is an independent field emission electron unit, it is convenient for replacement, assembly and integration. Thirdly, the method of manufacturing the field emission electron source 10 can easily fix the carbon nanotube linear structure 110 with the insulating layer 120 and control the thickness of the insulating layer 120, thereby allowing the field emission electron source 10 to be fixed. The voltage applied to the source can be controlled. Fourth, the manufacturing method of the field emission electron source 10 has high manufacturing efficiency because a plurality of field emission electron sources 10 can be formed at one time. In addition, the structure is easy and the cost is low.

(Example 3)
Referring to FIG. 5, the third embodiment of the present invention provides a field emission display device 12. The field emission display device 12 includes a cathode electrode 150 and a field emission electron source 10. The field emission electron source 10 has a first end and a second end opposite to each other in a direction extending to the central axis. The first end of the field emission electron source 10 is electrically connected to the cathode electrode 150. That is, the exposed carbon nanotube linear structure 110 is electrically connected to the cathode electrode 150 at the first end of the field emission electron source 10. The conductive ring 130 is installed at the second end of the field emission electron source 10 and is insulated from the carbon nanotube linear structure 110 by the insulating layer 120. The conductive ring 130 is a grid of the field emission display device 12. By applying a voltage between the conductive ring 130 and the cathode electrode 150, a voltage is formed between the conductive ring 130 and the end of the carbon nanotube linear structure 110, and the electron emission of the carbon nanotube linear structure 110 is prevented. Realize. Further, as long as it is ensured that the cathode electrode 150 is electrically connected to the carbon nanotube linear structure 110, the material and shape of the cathode electrode 150 are not limited and can be selected as necessary.

  Furthermore, the conductive ring 130 can be installed at the first end of the field emission electron source 10. At this time, the conductive ring 130 installed at the first end of the field emission electron source 10 contacts the cathode electrode 150 and is electrically insulated from the conductive ring 130 installed at the second end of the field emission electron source 10. The The conductive ring 130 installed at the first end of the field emission electron source 10 is fixed to the surface of the cathode electrode 150 by a method such as welding. Thereby, the field emission electron source 10 is firmly fixed to the cathode electrode 150, and the contact property between the carbon nanotube linear structure 110 and the cathode electrode 150 is excellent.

(Example 4)
Referring to FIG. 6, the fourth embodiment of the present invention provides a method for manufacturing the field emission electron source 20. The method of manufacturing the field emission electron source 20 includes the step of providing the carbon nanotube linear structure 110 (S20), the step of covering the surface of the carbon nanotube linear structure 110 with the insulating material 124 (S21), and the insulating material. A step of installing a plurality of conductive rings 130 on the surface of 124 at an interval (S22), and cutting the carbon nanotube linear structure 110 covered with the insulating material 124 and provided with the plurality of conductive rings 130, Forming the field emission electron source preliminary body 212 (S23), and sintering the insulating material 124 in the plurality of field emission electron source preliminary bodies 212 to form the insulating layer 120, thereby forming a plurality of field emission electron sources. 20 (S24).

  The manufacturing method of the field emission electron source 20 according to the fourth embodiment of the present invention is basically the same as the manufacturing method of the field emission electron source 10 according to the first embodiment, except that the insulating material 124 is different from the fourth embodiment. Prior to forming the insulating layer 120 by sintering, the carbon nanotube linear structure having the plurality of conductive rings 130 is cut by covering the insulating material 124, and a plurality of field emission electron source reserves 212. Is formed, and then the field emission electron source 20 is sintered.

  In step (S24), the insulating material 124 is not limited and can be selected as necessary. The insulating material 124 is, for example, any one of vacuum ceramic, aluminum oxide, Teflon (registered trademark), and nano clay-polymer composite material. Since the insulating material 124 contracts in the process of sintering, when the insulating material 124 is sintered, the insulating layer 120 formed in the field emission electron source 20 contracts and dents to form the carbon nanotube linear structure 110. A part of is exposed. Thereby, a part of the carbon nanotube linear structure 110 is not covered with the insulating layer 120. The shape of the space in which the insulating layer 120 is recessed inside the field emission electron source 20 is related to the shrinkage rate of the insulating material 124, and the space becomes smaller as the distance from the cut surface of the field emission electron source 20 increases. The maximum length of a part of the exposed carbon nanotube linear structure 110 is smaller than the width of the conductive ring 130. This ensures that the insulating layer 120 is covered with the conductive ring 130.

(Example 5)
Referring to FIG. 7, the fifth embodiment of the present invention provides a field emission electron source 20. The field emission electron source 20 includes a carbon nanotube linear structure 110, an insulating layer 120, and a conductive ring 130. The surface of the carbon nanotube linear structure 110 is covered with an insulating layer 120. At least one conductive ring 130 is installed on at least one end of the carbon nanotube linear structure 110 covered with the insulating layer 120. The carbon nanotube linear structure 110, the insulating layer 120, and the conductive ring 130 are disposed coaxially. Both ends of the carbon nanotube linear structure 110 are exposed from the insulating layer 120.

  The structure of the field emission electron source 20 of the fifth embodiment of the present invention is basically the same as the structure of the field emission electron source 10 of the second embodiment, but there are the following differences. At the end portion of the field emission electron source 20 where the conductive ring 130 is installed, the insulating layer 120 is recessed inside the field emission electron source 20 to form a space. A part of the carbon nanotube linear structure 110 is located in the recessed space, is exposed from the insulating layer 120, and is not covered with the insulating layer 120. The length of a part of the carbon nanotube linear structure 110 exposed without being covered with the insulating layer 120 is smaller than the width of the conductive ring 130. The end of the carbon nanotube linear structure 110 is located on the same plane as the cut surface of the conductive ring 130.

(Example 6)
Referring to FIG. 8, the sixth embodiment of the present invention provides a method for manufacturing the field emission electron source 30. The method of manufacturing the field emission electron source 30 includes the step of providing the carbon nanotube linear structure 110 (S30), the step of covering the surface of the carbon nanotube linear structure 110 with the insulating layer 120 (S31), and the insulating layer. The step of installing a plurality of conductive rings 130 on the surface of 120 at intervals (S32), and the step of covering the surface of the insulating layer 120 exposed between two adjacent conductive rings 130 with the insulating ring 122 (see FIG. S33), and cutting the plurality of conductive rings 130, the insulating layer 120, and the carbon nanotube linear structure 110 to form the plurality of field emission electron sources 30 (S34).

  The manufacturing method of the field emission electron source 30 according to the sixth embodiment of the present invention is basically the same as the manufacturing method of the field emission electron source 10 according to the first embodiment, with the following differences. The method of manufacturing the field emission electron source 30 further includes the step of coating the insulating ring 122 on the surface of the insulating layer 120 exposed between the two adjacent conductive rings 130. The manufacturing method of the insulating ring 122 is basically the same as the manufacturing method of the insulating layer 120. Further, the thickness of the insulating ring 122 is the same as the thickness of the conductive ring 130. Thereby, the outer diameter of the field emission electron source 30 becomes the same.

  The field emission electron source 30 having the insulating ring 122 has the following excellent points. First, a plurality of field emission electron sources 30 can be installed in parallel, and when emitting electrons, the space in which the gas exists is reduced, and the influence of the gas on the electron emission is reduced. Second, since the field emission electron sources 30 have the same outer diameter, when a plurality of field emission electron sources 30 are installed in parallel, the area where the field emission electron sources 30 come into contact with each other is increased, and the field emission electrons are increased. The acting force between the sources 30 can be increased, and the field emission electron source 30 can be tightly coupled.

  Further, the manufacturing process of the conductive ring 130 and the manufacturing process of the insulating ring 122 can be interchanged. That is, first, after a plurality of insulating rings 122 are installed at intervals on the surface of the insulating layer 120, the surface of the insulating layer 120 exposed between two adjacent insulating rings 122 is covered with the conductive ring 130. . Thereby, since the insulating ring 122 and the insulating layer 120 can form an integrally molded structure, the manufacturing process is simplified and the cost is reduced.

(Example 7)
Referring to FIG. 9, the seventh embodiment of the present invention provides a method for manufacturing the field emission electron source array 100. The method of manufacturing the field emission electron source array 100 includes the step of providing the carbon nanotube linear structure 110 (S40), the step of covering the surface of the carbon nanotube linear structure 110 with the insulating layer 120 (S41), the insulation A step (S42) of forming a plurality of conductive rings 130 at intervals on the surface of the layer 120 to form a preliminary body 312 of a field emission electron source, and a plurality of field emission electron source preliminary bodies 312 are disposed in parallel. Forming the field emission electron source array preliminary body 101 (S43) and cutting the field emission electron source array preliminary body 101 to form a plurality of field emission electron source arrays 100 (S44).

  The manufacturing method of the field emission electron source array 100 of Example 7 of the present invention is basically the same as the manufacturing method of the field emission electron source 10 of Example 1, with the following differences. In the method of manufacturing the field emission electron source array 100, a plurality of field emission electron source spares 312 provided with a plurality of conductive rings 130 are placed in parallel, and then the plurality of field emission electron source spares 312 are simultaneously cut. Then, a plurality of field emission electron source arrays 100 are formed.

  In the step (S43), installing in parallel means that the plurality of field emission electron source spare bodies 312 are extended in parallel along the same direction (for example, the same direction is the X direction). In addition, the conductive rings 130 installed in the preliminary bodies 312 of the field emission electron sources correspond to the conductive rings 130 installed in the adjacent preliminary bodies 312 of the field emission electron sources and have the same X coordinate value. Point to. That is, the Nth conductive ring 130 in the preliminary body 312 of each field emission electron source has the same X coordinate value, and the (N + 1) th conductive ring 130 in the preliminary body 312 of each field emission electron source has the same X coordinate value. Have Since the plurality of field emission electron source spares 312 are installed in parallel, when simultaneously cutting the plurality of field emission electron source spares 312, the cutting position can be easily controlled, and the plurality of field emission electrons formed are formed. The source array 100 is neatly arranged. In the field emission electron source array 100, adjacent field emission electron source spares 312 are installed in contact with each other, and conductive rings 130 having the same X coordinate value are installed in electrical contact with each other.

  Since the plurality of field emission electron source reserves 312 have strong attraction between each other, the plurality of field emission electron source reserves 312 are closely arranged. Thus, when the field emission electron source array preliminary body 101 is cut, the plurality of field emission electron source preliminary bodies 312 are not dispersed. Thereby, the formed field emission electron source array 100 can be easily integrated, installed, and driven. Further, due to a manufacturing process or the like, the preliminary bodies 312 of different field emission electron sources may have a slight misalignment in the conductive ring 130 having the same X coordinate. The field emission of each field emission electron source 10 of the source array 100 is not affected.

  In step (S44), since the plurality of field emission electron source spares 312 are installed in parallel, the position where the field emission electron source array spare 101 is cut is preferably between both surfaces of the conductive ring 130. . As a result, the conductive ring 130 is installed on at least one end of the formed field emission electron source array 100. In the step of cutting the preliminary body 312 of the field emission electron source, when the cutting direction is inclined (that is, the cutting direction is not perpendicular to the direction of the central axis of the preliminary body 312 of the field emission electron source), part of the field emission There is a possibility that the conductive ring 130 is not installed at the cut position of the preliminary body 312 of the electron source. In this case, there is a possibility that some of the formed field emission electron sources 30 cannot emit electrons, or the field emission electron source array 100 cannot emit electrons uniformly. Therefore, it is preferable that the cutting direction be perpendicular to the central axis of the preliminary body 312 of the field emission electron source. However, as long as it is ensured that the field emission electron source array 100 can emit electrons uniformly, the cutting direction is not perpendicular to the central axis of the preliminary body 312 of the field emission electron source due to other reasons such as a manufacturing process. Also good. At this time, the cutting direction is inclined at a specific angle with the direction of the central axis of the preliminary body 312 of the field emission electron source.

  The manufacturing method of the field emission electron source array 100 has the following excellent points. First, a plurality of independent field emission electron source arrays 100 can be manufactured at a time, and each field emission electron source array 100 can be used as an independent field emission unit. Second, the field emission current of the field emission electron source array 100 is increased. Third, the field emission electron source array 100 can form a new field emission electron source array according to a specific pattern, which makes it advantageous to integrate field emission elements, and easily replace and adjust the field emission electron source array 100 And can be moved. Fourth, since each carbon nanotube linear structure 110 in the field emission electron source array 100 is firmly fixed to the insulating layer, the field emission electron source array 100 can receive a strong electric field force.

  The field emission electron source array 100 includes a plurality of field emission electron sources 10, and the plurality of field emission electron sources 10 are installed in parallel. By installing in parallel, the plurality of field emission electron sources 10 extend along the same direction and have the same length in the direction, and the conductive rings 130 at the same end of each field emission electron source 10 are mutually connected. The surfaces of the plurality of conductive rings 130 at the end of the field emission electron source array 100 are horizontal cut surfaces. Further, the field emission electron source 10 has a first end and a second end facing each other in the extending direction. The conductive ring 130 is installed at at least one end of the field emission electron source 10. That is, all the conductive rings 130 installed in each field emission electron source 10 can be installed at the first end of the field emission electron source 10, and all the conductive rings 130 installed in each field emission electron source 10. Can be installed at the second end of the field emission electron source 10. Alternatively, the conductive ring 130 may be installed at the first end and the second end simultaneously. In addition, the conductive rings 130 installed at the same end of two adjacent field emission electron sources 10 are in electrical contact with each other.

  Referring to FIG. 10, after the field emission electron source array 100 is formed, a conductive layer 140 is installed at one end of the field emission electron source array 100. The plurality of conductive rings 130 at one end of the field emission electron source array 100 are covered with the conductive layer 140, and the conductive layer 140 is electrically connected to the plurality of conductive rings 130 at one end of the field emission electron source array 100. . Since the plurality of field emission electron sources 10 in the field emission electron source array 100 are installed in parallel, a part of the surface of the plurality of conductive rings 130 on the outer periphery of the field emission electron source array 100 is exposed. Therefore, the conductive layer 140 is continuously attached to a part of the surface of the exposed conductive ring 130. Here, the surface refers to a surface that does not come into contact with the insulating layer 120 between the opposing surfaces in the direction of the central axis of the conductive ring 130. The conductive layer 140 is electrically connected to the plurality of conductive rings 130 at the outer periphery of one end of the field emission electron source array 100, so that the conductive layer 140 is connected to all the conductive rings 130 at the same end of the field emission electron source array 100. Can be electrically connected. Thereby, by applying a voltage between the conductive layer 140 and the carbon nanotube linear structure 110, the plurality of field emission electron sources 10 emit electrons simultaneously, and a large field emission current is formed. Moreover, it is applied to a high efficiency electron-emitting device.

(Example 8)
Referring to FIG. 11, the eighth embodiment of the present invention provides a field emission display device 22. The field emission display device 22 includes a cathode electrode 150 and a field emission electron source array 100. The field emission electron source array 100 has a first end and a second end which are opposed to each other in a direction extending to the central axis. The first end of the field emission electron source array 100 is electrically connected to the cathode electrode 150.

  The structure of the field emission display device 22 of Example 8 of the present invention is basically the same as the structure of the field emission display device 12 of Example 3, with the following differences. The field emission display device 12 according to the third embodiment uses the field emission electron source 10, but the field emission display device 22 according to the eighth embodiment uses the field emission electron source array 100. A conductive layer 140 is provided at the second end of the field emission electron source array 100.

Example 9
Referring to FIG. 12, the ninth embodiment of the present invention provides a method for manufacturing the field emission electron source 200. The method of manufacturing the field emission electron source 200 includes a step S50 of providing the carbon nanotube linear structure 110, a step S51 of covering the surface of the carbon nanotube linear structure 110 with the insulating material 124, and a surface of the insulating material 124. A step S52 of forming a plurality of conductive rings 130 at intervals to form a preliminary body 412 of a field emission electron source, and a plurality of preliminary bodies 412 of a plurality of field emission electron sources are installed in parallel to form a field emission electron source array. Step S53 for forming the preliminary body 201, and step S54 for cutting the field emission electron source array preliminary body 201, sintering the insulating material 124 to form the insulating layer 120, and forming a plurality of field emission electron source arrays 200. And including.

  The manufacturing method of the field emission electron source 200 according to the ninth embodiment of the present invention is basically the same as the manufacturing method of the field emission electron source 20 according to the fourth embodiment, with the following differences. In the method of manufacturing the field emission electron source array 200, first, a plurality of field emission electron source spares 412 provided with a plurality of conductive rings 130 are installed in parallel, and then a plurality of field emission electron source spares are installed. 412 is cut at the same time, and finally, the insulating material 124 is sintered to form the insulating layer 120 to obtain a plurality of field emission electron source arrays 200. Each field emission electron source array 200 includes a plurality of field emission electron sources 20 installed in parallel.

10, 20, 30 Field emission electron source 12, 22 Field emission display device 100, 200 Field emission electron source array 101, 201 Field emission electron source array preliminary body 110 Carbon nanotube linear structure 112, 212, 312, 412 Field emission Electron source spare 120 Insulating layer 122 Insulating ring 124 Insulating material 130 Conducting ring 140 Conducting layer 150 Cathode electrode

Claims (3)

Providing a carbon nanotube linear structure;
A second step of covering the surface of the carbon nanotube linear structure with an insulating layer;
A third step of installing a plurality of conductive rings at intervals on the surface of the insulating layer to form a preliminary body of a field emission electron source;
Cutting a preliminary body of the field emission electron source to form a plurality of field emission electron sources; and
At least one of the conductive rings is installed at at least one end of each of the field emission electron sources,
The electric field, wherein the conductive ring, the insulating layer, and the carbon nanotube linear structure are exposed from a cut surface obtained by cutting the preliminary body of the field emission electron source and are located on the same plane. Manufacturing method of emission electron source. Providing a carbon nanotube linear structure;
A second step of covering the surface of the carbon nanotube linear structure with an insulating layer;
A third step of installing a plurality of conductive rings at intervals on the surface of the insulating layer to form a preliminary body of a field emission electron source;
A fourth step of installing a plurality of field emission electron source spares in parallel, electrically connecting adjacent conductive rings, and forming a field emission electron source array spare;
Cutting the field emission electron source array preliminary body to form a plurality of field emission electron source arrays,
The conductive ring, the insulating layer, and the carbon nanotube linear structure are exposed from a cut surface obtained by cutting the field emission electron source array preliminary body and are located on the same plane. Manufacturing method of emission electron source array. Providing a carbon nanotube linear structure;
A second step of coating the surface of the carbon nanotube linear structure with an insulating material;
A third step of installing a plurality of conductive rings on the surface of the insulating material at an interval, wherein the conductive ring has two surfaces facing each other;
A fourth step of cutting a carbon nanotube linear structure coated with the insulating material and provided with a plurality of conductive rings, wherein the fourth step is along one surface of the conductive ring or on two surfaces of the conductive ring; A fourth step of cutting from a position between to form a preliminary body of a plurality of field emission electron sources;
A fifth step of sintering an insulating material in a plurality of field emission electron source preliminary bodies to form an insulating layer and forming a plurality of field emission electron sources;
At least one conductive ring is installed at at least one end of each of the field emission electron sources;
The method of manufacturing a field emission electron source, wherein the end of the carbon nanotube linear structure is exposed without being covered with an insulating layer.