JP2004179026A - Manufacturing method of electron emitting element, and manufacturing method of display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To surely avoid disorder like gas generation due to a residual substance or inadequacy of adhesion force of an emitter layer by optimizing baking treatment of the emitter layer. <P>SOLUTION: The manufacturing method of the electron emitting element comprises a process of forming a cathode electrode 5 on a supporting substrate 4, a process of forming an emitter layer 10 containing carbon nanotubes and a binder material on the cathode electrode 5 through a resistor layer 21, a process of baking the emitter layer 10 with a first baking temperature in open air, and a process of baking the emitter layer 10 with a second baking temperature higher than the first baking temperature in an inert gas atmosphere. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for manufacturing an electron-emitting device that emits electrons and a method for manufacturing a display device.
[0002]
[Prior art]
In recent years, carbon crystals having a tube structure formed by winding a carbon graphite sheet called carbon nanotubes have been discovered. The diameter of carbon nanotubes is generally about 1 nm to 200 nm (recently 0.5 nm to 300 nm). Carbon nanotubes are broadly classified into single-walled carbon nanotubes composed of a single graphite sheet and multi-walled carbon nanotubes composed of two or more graphite sheets. Such a crystal having a nanometer-sized tube structure is regarded as a unique substance like no other.
[0003]
At present, methods for producing carbon nanotubes include a method using a laser ablation method, a method using an arc method, and a method using a CVD (Chemical Vapor Deposition) method. According to the laser ablation method, as described in Non-Patent Document 1 below, a graphite target containing nickel and cobalt is evaporated by a pulse laser in a reaction chamber heated to 1000 ° C. or higher. Thereby, carbon nanotubes grow on the side walls of the chamber. This method is characterized in that the length of the carbon nanotube can be controlled by changing the conditions of the pulse laser, and that the purity of the produced carbon nanotube is extremely high. In this method, when producing single-walled carbon nanotubes, a catalyst such as Ni (nickel), Co (cobalt), or Fe (iron) is required.
[0004]
[Non-patent document 1]
D. S. Bethune, C.I. H. Kiang, M .; S. de Vries, G. Gorman, R.A. Savoy, J .; Vazque, R .; Beyers, "Nature", 1993, Vol 363, p. 605
[0005]
According to the arc method, as described in Non-Patent Document 2 below, a DC arc discharge is performed using an electrode made of carbon in an atmosphere of 100 Torr of argon. As a result, carbon nanotubes grow together with carbon fine particles on a part of the negative electrode. This method is characterized in that the amount of carbon nanotubes produced is much larger than that of the laser ablation method. Also in this method, when producing single-walled carbon nanotubes, a catalyst such as Ni, Co, and Fe is required.
[0006]
[Non-patent document 2]
TW Ebbesen, PM Ajayan, "Nature", 1992, Vol 358, p. 220
[0007]
According to the CVD method, as described in Non-Patent Document 3 below, Ni (nickel) is used as a catalyst metal and a Ni-coated substrate or a Ni substrate is used. Introduce, generate plasma, and pretreat Ni with ammonia plasma. Next, a carbon source gas such as acetylene is introduced. At this time, a gas such as ammonia, hydrogen, or argon may be mixed. The film forming temperature at this time is 500 to 550 ° C.
[0008]
[Non-Patent Document 3]
O. M. Kuttle, O .; Groening, C.I. Emmenegger, L.A. Schlapbach, "Appl. Phys. Lett.", 1998, Vol 73, p. 2113
[0009]
The carbon nanotubes produced by such a method have semiconducting properties and metallic properties depending on the winding and diameter of the graphite sheet. Due to these unique properties, carbon nanotubes are expected to be applied to various electronic devices and electric devices. As one of the most prominent examples, there is an application to a field emission display (FED), which is a field emission type flat display device (display). When a carbon nanotube is attached to a cathode electrode as an electron emission source and an electric field exceeding a certain threshold is applied, an energy barrier on the nanotube surface becomes low and thin due to the concentration of the electric field, and electrons are emitted into a vacuum by a tunnel effect. This phenomenon is called field emission.
[0010]
In the FED, by utilizing the above-described field emission phenomenon, electrons are emitted from an electrically selected (addressed) emitter by concentration of an electric field, and the electrons collide with the phosphor on the anode substrate side, thereby causing the phosphor to emit light. Images are displayed by excitation and emission. Since carbon nanotubes have a high aspect ratio and a very small radius of curvature at the tip, they are regarded as promising as an emitter material for realizing high luminous efficiency.
[0011]
In addition, since carbon nanotubes are very fine particles (powder), when an emitter is formed using carbon nanotubes, it is necessary to fix the carbon nanotubes to a substrate. In general, a highly conductive binder material such as a silver paste or an ITO (Indium Tin Oxide) solution is used for fixing the carbon nanotubes. Specifically, carbon nanotubes are mixed into a binder material to form a paste (or a slurry or an ink), and the paste is applied to the surface of the substrate by a printing method, a spray method, a die coater method, or the like. Then, the carbon nanotubes are fixed on the substrate using the adhesive property of the binder material.
[0012]
Here, with respect to the application of a paste material containing carbon nanotubes, for example, Patent Literature 1 below discloses a plurality of vehicles each including a vehicle in which a resin is dissolved in an organic solvent and a plurality of layers of cylindrical graphite dispersed in the vehicle. It describes that a conductive paste is formed from carbon nanotubes and that the conductive paste is used for forming an anode electrode on which a phosphor layer of a fluorescent display tube is formed. Patent Document 1 describes that after forming a pattern using the conductive paste, firing is performed at a predetermined temperature.
[0013]
[Patent Document 1]
JP-A-2000-63726 (pages 2 to 3, FIG. 2)
[0014]
Regarding a method of forming an emitter using carbon nanotubes, for example, Patent Document 2 below discloses a step of attaching a cathode conductor to an insulating substrate, and forming a carbon nanotube, a fullerene, a nanoparticle, a nanocapsule and a carbon on the cathode conductor. A step of applying a paste material containing at least one of the nanohorns to form a carbon layer, a step of applying an adhesive tape to the dried carbon layer, and then removing the adhesive tape to form an emitter; and Forming a gate electrode at a position separated from the electron emission source. Patent Document 2 describes that the dried carbon layer is baked at about 500 ° C. for about 15 minutes in the air to remove organic components.
[0015]
[Patent Document 2]
JP 2001-35360 A (page 2, page 4-5, FIG. 1-4)
[0016]
Patent Document 3 below discloses a process of forming a cathode electrode on a support, a process of forming an insulating layer on the support and the cathode electrode, and a process of forming a gate electrode having an opening on the insulating layer. Forming a second opening communicating with the opening formed in the gate electrode in the insulating layer; and forming a metal thin film or an organic metal film on the surface of the portion of the cathode electrode located at the bottom of the second opening. A method of manufacturing a cold cathode field emission device, which includes a step of forming a carbon thin film selective growth region by forming a compound thin film and a step of forming a carbon thin film on the carbon thin film selective growth region, is described.
[0017]
[Patent Document 3]
JP-A-2002-197965 (page 2, page 18, FIG. 5)
[0018]
Patent Document 4 below discloses a step of forming a cathode electrode on a support, a step of forming an insulating layer on a support including the cathode electrode, and a step of forming a gate electrode on the insulating layer. Forming an opening in which the cathode electrode is exposed at the bottom at least in the insulating layer; and forming an electron emission electrode made of a conductive composition including conductive particles and a binder on the cathode electrode exposed at the bottom of the opening. A method for manufacturing a cold-cathode field emission device, comprising the steps of: exposing conductive particles to the surface of an electron-emitting electrode by removing a binder in a surface portion of the electron-emitting electrode; Japanese Patent Application Laid-Open No. H11-163873 discloses that pre-baking for removing moisture contained in a conductive composition layer is performed in air at 400 ° C. for 30 minutes, and firing of an electron-emitting electrode after lift-off is performed. It is described that the drying is performed in a dry atmosphere at 400 ° C. for 30 minutes.
[0019]
[Patent Document 4]
JP 2001-43790 A (Page 2, Page 7-10, FIG. 1-9)
[0020]
[Problems to be solved by the invention]
By the way, conventionally, when manufacturing an electron-emitting device using a fibrous emitter material such as a carbon nanotube, an emitter layer is formed on a substrate using a composite material obtained by mixing a binder material and a carbon nanotube. The carbon nanotubes are fixed on the substrate by firing and solidifying the emitter layer. At that time, in order to sinter the binder material contained in the emitter layer, it is necessary to apply a temperature of about 500 ° C. to the entire substrate. However, if the emitter layer is fired at this temperature, the carbon nanotube itself may be burned out. In addition, if the firing temperature is lowered to avoid burning of the carbon nanotubes, for example, organic substances contained in the binder material will remain, and the gas emission resulting from this residue will deteriorate the field emission characteristics, or cause the emitter to emit light to the substrate. Failures such as insufficient adhesion strength of the layer may occur.
[0021]
The present invention has been made in order to solve the above-mentioned problems, and an object of the present invention is to optimize the baking treatment of the emitter layer to generate outgas due to the residue and to improve the adhesion of the emitter layer. It is an object of the present invention to provide a method for manufacturing an electron-emitting device and a method for manufacturing a display device, which can reliably avoid problems such as shortage.
[0022]
[Means for Solving the Problems]
The method of manufacturing an electron-emitting device according to the present invention includes a step of forming an emitter layer containing an emitter material and a binder material on a cathode electrode, a step of firing the emitter layer in air at a first firing temperature, Baking the layer in an inert gas atmosphere or in a vacuum at a second baking temperature higher than the first baking temperature.
[0023]
Further, in the method of manufacturing a display device according to the present invention, as a manufacturing process of the electron-emitting device, a step of forming an emitter layer containing an emitter material and a binder material on the cathode electrode; The method includes a step of firing at a firing temperature and a step of firing the emitter layer at a second firing temperature higher than the first firing temperature in an inert gas atmosphere or vacuum.
[0024]
In the method for manufacturing an electron-emitting device and the method for manufacturing a display device, after the emitter layer is formed on the cathode electrode, firing of the emitter layer is performed in two steps, that is, firing the emitter layer at a first firing temperature in the air. And the step of firing the emitter layer at a second firing temperature higher than the first firing temperature in an inert gas atmosphere or in a vacuum, thereby burning and burning organic substances contained in the binder material. After the evaporation, the adhesion strength of the emitter layer can be sufficiently increased without burning off the emitter material such as carbon nanotubes.
[0025]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0026]
FIG. 1 is a sectional view showing an example of a panel structure of a display device to which the present invention is applied, and FIG. 2 is an exploded perspective view thereof. 1 and 2, a cathode panel (cathode substrate) 1 and an anode panel (anode substrate) 2 are arranged to face each other with a predetermined gap therebetween, and the panels 1 and 2 are integrated by a frame 3. As a result, one panel structure (display panel) for displaying images is formed.
[0027]
A plurality of electron-emitting devices are formed on the cathode panel 1. A large number of these electron-emitting devices are formed in a two-dimensional matrix in an effective region (a region that actually functions as a display portion) of the cathode panel 1. Each electron-emitting device includes an insulating support substrate (eg, a glass substrate) 4 serving as a base of the cathode panel 1, a cathode electrode 5, an insulating layer 6, and a gate sequentially formed on the support substrate 4 in a stacked state. It comprises an electrode 7, a gate hole 8 formed in the gate electrode 7 and the insulating layer 6, and an electron emission portion 9 formed at the bottom of the gate hole 8.
[0028]
The cathode electrode 5 is formed in a stripe shape so as to form a plurality of cathode lines. The gate electrode 7 is formed in a stripe shape so as to form a plurality of gate lines crossing (orthogonal to) each cathode line. The gate hole 8 includes a first opening 8A formed in the gate electrode 7 and a second opening 8B formed in the insulating layer 6 in a state of communicating with the first opening 8A. I have. The electron emission portion 9 is formed by an emitter layer 10 mainly containing a fibrous emitter material and a binder material (matrix). On the surface of the emitter layer 10, a plurality of carbon nanotubes 11 serving as a fibrous emitter material are arranged. One end of each carbon nanotube 11 projects vertically from the surface of the emitter layer 10, and the other end is embedded in the binder material of the emitter layer 10.
[0029]
On the other hand, the anode panel 2 includes a transparent substrate 12 serving as a base, a phosphor layer 13 and a black matrix 14 formed on the transparent substrate 12, and a transparent substrate 12 covering the phosphor layer 13 and the black matrix 14. And an anode electrode 15 formed thereon. The phosphor layer 13 is composed of a phosphor layer 13R for emitting red light, a phosphor layer 13G for emitting green light, and a phosphor layer 13B for emitting blue light. The black matrix 14 is formed between the phosphor layers 13R, 13G, and 13B for each color emission. The anode electrode 15 is formed in a stacked state over the entire effective area of the anode panel 2 so as to face the electron-emitting device of the cathode panel 1.
[0030]
The cathode panel 1 and the anode panel 2 are joined via a frame 3 at their outer peripheral portions (peripheral portions). Further, a through-hole 16 for evacuation is provided in an ineffective area (an area outside the effective area and not actually functioning as a display portion) of the cathode panel 1. A chip tube 17 that is sealed off after evacuation is connected to the through hole 16. However, since FIG. 1 shows a state in which the display device has been assembled, the tip tube 17 has already been sealed off. Also, in FIGS. 1 and 2, the illustration of the withstand pressure support (spacer) interposed in the gap between the panels 1 and 2 is omitted.
[0031]
In the display device having the above-described panel structure, a relative negative voltage is applied to the cathode electrode 5 from the cathode electrode control circuit 18, and a relative positive voltage is applied to the gate electrode 7 from the gate electrode control circuit 19. A positive voltage higher than that of the gate electrode 7 is applied to the anode electrode 15 from the anode electrode control circuit 20. When an image is actually displayed in such a display device, for example, a scanning signal is input to the cathode electrode 5 from the cathode electrode control circuit 18, and a video signal is input to the gate electrode 7 from the gate electrode control circuit 19. Alternatively, a video signal is input to the cathode electrode 5 from the cathode electrode control circuit 18, and a scanning signal is input to the gate electrode 7 from the gate electrode control circuit 19.
[0032]
As a result, a voltage is applied between the cathode electrode 5 and the gate electrode 7, whereby the electric field is concentrated on the sharp portion of the electron emitting portion 9 (the tip portion of the carbon nanotube 11). Electrons are emitted from the electron emitting portion 9 into the vacuum through the energy barrier. The emitted electrons are attracted to the anode electrode 15 and move to the anode panel 2 side, and collide with the phosphor layers 13 (13R, 13G, 13B) on the transparent substrate 12. As a result, the phosphor layer 13 emits light when excited by the collision of electrons, so that a desired image can be displayed on the display panel by controlling the light emitting position in pixel units.
[0033]
Subsequently, a specific example of the method for manufacturing the electron-emitting device according to the embodiment of the present invention will be described with reference to FIGS.
[0034]
First, as shown in FIG. 3A, a cathode electrode (conductive layer) 5 is formed on a support substrate 4 serving as a base of the cathode panel 1 using a conductive material for forming a cathode electrode. The cathode electrode 5 is formed of, for example, a chromium layer having a thickness of about 0.2 μm formed by a sputtering method.
[0035]
Next, a SiCN film is formed on the entire surface of the support substrate 4 by, for example, a sputtering method, and as shown in FIG. The resistance layer 21 is formed. The resistance layer 21 reduces the effective voltage acting on the emitter by increasing the voltage drop due to the resistance when the discharge current to the emitter increases, and conversely, when the discharge current to the emitter decreases, the resistance layer 21 It serves to stabilize the discharge current by increasing the effective voltage that acts. The resistance layer 21 is formed as needed.
[0036]
Next, a process for arranging the carbon nanotubes 11 serving as an emitter material on the resistance layer 21 (on the cathode electrode 5 when the resistance layer 21 is not formed) is performed. Specifically, while using organotin and organoindium, which are thermally decomposable organic metals, as a binder material, and powder of carbon nanotubes as an emitter material, these are dispersed in a volatile solution such as butyl acetate under the following conditions. A mixed solution is obtained. At that time, an ultrasonic treatment may be performed to improve the dispersibility of the carbon nanotube. The diluent may be aqueous or non-aqueous, but it is assumed that the dispersant varies depending on which is used. It is also possible to mix other additives. As the carbon nanotube, one having an extremely elongated tube structure (fibrous shape) having an average diameter of 1 nm and an average length of 1 μm is used, for example.
[0037]
(Conditions for producing a mixed solution)
Organic tin and organic indium: 10 to 50% by mass
Butyl acetate: 30 to 80% by mass
Dispersant (for example, sodium dodecyl sulfate): 0.1 to 5% by mass
Carbon nanotube: 0.001 to 20% by mass
[0038]
In addition, as an emitter material, a carbon nanofiber can be used other than the carbon nanotube. As the binder material, in addition to the above-mentioned thermally decomposable organic metals, for example, metal salts such as tin chloride and indium chloride, inorganic materials such as water glass, and metal pastes such as silver paste can be used.
[0039]
Subsequently, the emitter layer (composite layer) 10 containing the carbon nanotubes and the binder material is formed as shown in FIG. 3C by applying the above mixed solution onto the supporting substrate 4 by a spray method or the like. I do. This emitter layer 10 can also be formed using a printing method.
[0040]
Thereafter, the emitter layer 10 is fired under predetermined conditions. Here, as shown in FIG. 6, the emitter layer 10 is baked in two steps under different atmosphere conditions and temperature conditions. First, in a first step, the emitter layer 10 is fired in the air at a first firing temperature T1. Next, in a second step, the emitter layer 10 is fired at a second firing temperature T2 in an inert gas atmosphere such as nitrogen gas. As a temperature condition in this case, the second firing temperature T2 is higher than the first firing temperature T1 (in other words, the first firing temperature T1 is lower than the second firing temperature T2). In the second step, the emitter layer 10 may be fired in a non-oxidizing atmosphere such as a vacuum, instead of the inert gas atmosphere.
[0041]
Thus, in the first step, by baking in the air, by appropriately setting the baking temperature (first baking temperature T1), organic substances and the like in the binder material can be burned and evaporated. Further, in the second step, the firing temperature (second firing temperature T2) is appropriately set by firing in an inert gas atmosphere, so that the carbon nanotubes are not burned off and the emitter is formed on the support substrate 4. The layer 10 can be firmly adhered. One example of the baking treatment conditions in the first step and the second step is shown below.
[0042]
(Baking process conditions of the first step)
Atmosphere: Air firing temperature (T1): 350 ° C
Firing time: 30 minutes (firing process conditions in the second step)
Atmosphere: Nitrogen (N ₂ ) gas atmosphere firing temperature (T2): 500 ° C
Firing time: 30 minutes
Here, when a thermally decomposable organic metal is used as the binder material, the first firing temperature T1 is set to 200 ° C. or higher and lower than 420 ° C. (preferably 380 ° C.), and the second firing temperature T2 is set to 420 ° C. As described above, the temperature may be set to less than 580 ° C. In this case, the lower limit temperature of the first firing temperature T1 is defined by the thermal decomposition temperature of the organic substance.
[0044]
When a metal salt is used as the binder material, the first firing temperature T1 is set at 250 ° C. or higher and lower than 420 ° C. (preferably 350 ° C.), and the second firing temperature T2 is set at 420 ° C. or higher and 580 ° C. It may be set to less than. In this case, the lower limit temperature of the first firing temperature T1 is defined by a temperature at which a metal salt causes a elimination reaction (elimination reaction temperature).
[0045]
When water glass is used as the binder material, the first firing temperature T1 is set at 250 ° C. or higher and lower than 440 ° C. (preferably 400 ° C.), and the second firing temperature T2 is set at 440 ° C. or higher and 580 ° C. It may be set to less than. In this case, the lower limit temperature of the first firing temperature T1 is defined by the thermal decomposition temperature of the inorganic substance.
[0046]
When a metal paste is used as the binder material, the first firing temperature T1 may be set to 180 ° C. or more and less than 420 ° C., and the second firing temperature T2 may be set to 420 ° C. or more and less than 580 ° C. . In this case, the lower limit temperature of the first firing temperature T1 is defined by the thermal decomposition temperature of the organic substance contained in the metal paste.
[0047]
Next, the emitter layer 10 is processed into a stripe shape. Specifically, a resist material (photoresist) is applied by a spin coating method to form a resist film covering the emitter layer 10, and this resist film is patterned by a photolithography technique to serve as an etching mask. A resist pattern is formed on the emitter layer 10. Next, the portion excluding the emitter layer 10 covered with the resist pattern is removed by, for example, wet etching based on the following conditions, thereby forming the emitter layer 10 on the support substrate 4 as shown in FIG. It is formed in a stripe shape.
[0048]
(Wet etching conditions)
Etching solution: hydrochloric acid (HCL)
Etching time: 10 seconds to 30 minutes Etching temperature: 10 to 60 ° C
[0049]
At this time, if the carbon nanotubes are present in a region other than the desired region, the unnecessary carbon nanotubes are removed by etching using oxygen plasma or an oxidizing solution under the following conditions.
[0050]
(Oxygen plasma etching conditions)
Apparatus: RIE (reactive ion etching) apparatus Introduced gas: Oxygen-containing gas plasma excitation power: 500 W
Bias power: 0 to 150 W (DC or RF may be used, but RF is preferred)
Etching time: 10 seconds or more
(Oxidation solution etching conditions)
Solution: KMnO ₄
Etching temperature: 20-80 ° C
Etching time: 10 seconds to 20 minutes
Subsequently, by patterning the resistive layer 21 and the cathode electrode 5 by a well-known lithography technique and a reactive ion etching method (RIE method), the cathode electrode 5 is formed on the support substrate 4 as shown in FIG. Are formed in a stripe shape. At this point, a plurality of cathode lines are formed on the support substrate 4.
[0053]
Next, as shown in FIG. 4A, an insulating layer 6 is formed on the supporting substrate 4 so as to cover the stacked portion of the cathode electrode 5, the resistance layer 21, and the emitter layer 10, and furthermore, the insulating layer 6 As shown in FIG. 4B, a gate electrode (conductive layer) 7 is formed using a conductive material for forming a gate electrode. Specifically, an insulating layer 6 made of, for example, SiO _{2 having} a thickness of about 1 μm is formed on the entire surface of the support substrate 4 by a CVD method using TEOS (tetraethoxysilane) as a source gas. A gate electrode 7 made of chromium is formed thereon by a sputtering method.
[0054]
Next, an etching mask (not shown) is formed on the gate electrode 7, and a predetermined portion of the gate electrode 7 is etched using the etching mask, thereby forming an insulating mask on the insulating layer 6 as shown in FIG. The gate electrode 7 is formed in a stripe shape, and a first opening 8A penetrating the gate electrode 7 is formed. At this time, the stripe-shaped gate electrode 7 is formed so as to intersect (orthogonally) the cathode electrode 5 at a substantially right angle. Thus, a plurality of gate lines orthogonal to the cathode lines are formed on the support substrate 4.
[0055]
Next, the insulating layer 6 is etched by, for example, RIE through the first opening 8A of the gate electrode 7 to expose the surface of the emitter layer 10 as shown in FIG. An opening 8B is formed. Thus, a gate hole 8 including the first and second openings 8A and 8B is obtained. The gate hole 8 is formed, for example, in a circular shape having a diameter of 20 μm. Further, a plurality of (for example, several tens) gate holes 8 are formed per pixel.
[0056]
Next, by removing the binder material (matrix) in the upper layer of the emitter layer 10, the carbon nanotubes 11 are exposed on the surface of the emitter layer 10 at the bottom of the gate hole 8, as shown in FIG. As a method for removing the binder material in the upper layer portion of the emitter layer 10, an etching method (half etching) such as wet etching or dry etching can be preferably used. As an example, conditions for applying wet etching are shown below.
[0057]
(Wet etching conditions)
Etching solution: HCL 10%
Etching temperature: 10-60 ° C
Etching time: 5 to 60 seconds
Thereafter, as shown in FIG. 5C, the carbon nanotubes 11 are subjected to an orientation treatment so that the carbon nanotubes 11 stand up substantially vertically on the surface of the emitter layer 10. Specifically, for example, after adhering an adhesive tape (not shown) on the support substrate 4 from above the gate electrode 7, the adhesive tape is peeled off to orient the carbon nanotubes 11 substantially perpendicular to the support substrate 4. .
[0059]
In the above embodiment, in performing the firing of the emitter layer 10 in two steps, in the first step (first step), the emitter layer 10 is fired in the air at a first firing temperature T1. In the second step (next step), the emitter layer 10 is fired at the second firing temperature T2 in an inert gas atmosphere (or in a vacuum). However, the present invention is not limited to this. In the case where a paste or the like is used, as shown in FIG. 7, in a first step, the emitter layer 10 is fired at a second firing temperature T2 in an inert gas atmosphere (or in a vacuum). In step (b), the emitter layer 10 may be fired in the air at the first firing temperature T1. Further, the emitter layer 10 may be fired in three or more steps including the first step and the second step.
[0060]
【The invention's effect】
As described above, according to the present invention, as a method for manufacturing an electron-emitting device, after forming an emitter layer on a cathode electrode, the emitter layer is baked in two steps with different atmospheric and temperature conditions. In addition, it is possible to sufficiently increase the adhesion strength of the emitter layer without burning and evaporating the organic material or the like contained in the binder material and without burning off the emitter material such as carbon nanotubes. As a result, it is possible to provide an electron-emitting device having excellent electron-emitting characteristics without causing outgassing due to the residue at the time of firing and insufficient adhesion of the emitter layer.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view illustrating an example of a panel structure of a display device to which the present invention is applied.
FIG. 2 is an exploded perspective view showing an example of a panel structure of a display device to which the present invention is applied.
FIG. 3 is a process diagram (part 1) illustrating a specific example of the method for manufacturing the electron-emitting device according to the embodiment of the present invention.
FIG. 4 is a process chart (part 2) illustrating a specific example of the method for manufacturing the electron-emitting device according to the embodiment of the present invention.
FIG. 5 is a process chart (part 3) illustrating a specific example of the method for manufacturing the electron-emitting device according to the embodiment of the present invention.
FIG. 6 is a diagram showing an example of a temperature profile when firing an emitter layer.
FIG. 7 is a diagram showing another example of the temperature profile when firing the emitter layer.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Cathode panel, 2 ... Anode panel, 4 ... Support substrate, 5 ... Cathode electrode 6 ... Insulating layer, 7 ... Gate electrode, 8 ... Gate hole, 9 ... Electron emission part, 10 ... Emitter layer, 11 ... Carbon nanotube ( Emitter material)

Claims (8)

Forming an emitter layer containing an emitter material and a binder material on the cathode electrode;
Firing the emitter layer in air at a first firing temperature;
Baking the emitter layer in an inert gas atmosphere or in a vacuum at a second baking temperature higher than the first baking temperature. 2. The method according to claim 1, wherein a carbon nanotube is used as the emitter material. 2. The method according to claim 1, wherein a thermally decomposable organic metal, a metal salt, water glass, or a metal paste is used as the binder material. When the thermally decomposable organic metal is used as the binder material, the first firing temperature is set to 200 ° C. or higher and lower than 420 ° C., and the second firing temperature is set to 420 ° C. or higher and lower than 580 ° C. 2. The method for manufacturing an electron-emitting device according to claim 1, wherein: When the metal salt is used as the binder material, the first baking temperature is set to 250 ° C. or more and less than 420 ° C., and the second baking temperature is set to 420 ° C. or more and less than 580 ° C. The method for manufacturing an electron-emitting device according to claim 1. When the water glass is used as the binder material, the first firing temperature is set at 250 ° C or more and less than 440 ° C, and the second firing temperature is set at 440 ° C or more and less than 580 ° C. The method for manufacturing an electron-emitting device according to claim 1. When the metal paste is used as the binder material, the first firing temperature is set to 180 ° C or higher and lower than 420 ° C, and the second firing temperature is set to 420 ° C or higher and lower than 580 ° C. The method for manufacturing an electron-emitting device according to claim 1. As a manufacturing process of the electron-emitting device,
Forming an emitter layer containing an emitter material and a binder material on the cathode electrode;
Firing the emitter layer in air at a first firing temperature;
Baking the emitter layer in an inert gas atmosphere or in a vacuum at a second baking temperature higher than the first baking temperature.

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