JPH0945231A - Manufacture of electric field emitting cold cathode - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the convergence effect of electron beams by forming the structure of an electric field emitting cold cathode on a planar substrate, and then, fixing it by bending the electron emitting region. SOLUTION: A through hole 12 made in a plate-shaped substrate 11 is charged with low-melting point glass 13, and then a conductive layer, an insulating layer, and a gate layer are made. This gate layer and the insulating layer are etched to form a cavity to make an emitter layer, and then a sacrificed layer and an emitter electrode are made, and the sacrificed layer is etched off, thus an electric field emitting cathode having an electron emitting region 10 where an emitter electrode is made is obtained. Next, the rear of this substrate 11 is stuck fast to a jig and is heated, and the low-melting point metal 13 charged in the through hole 12 of the substrate 11 is sucked by suction, and also after bending the electron emitting region 10 into recess form, and then the low-melting point glass 13 is cooled and fixed.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a method for manufacturing a field emission cold cathode, and more particularly to a structure of a field emission cold cathode in which the divergence angle of an emitted electron beam is suppressed to a small value and a method for manufacturing the same.

[0002]

2. Description of the Related Art A field emission cold cathode has been developed as an electron source instead of a hot cathode utilizing thermionic emission. A field emission cold cathode has a high electric field (2
To 5 × 10 ⁷ V / cm or more) to emit electrons into the space. For this reason, although the sharpness of the tip is a condition that affects the characteristics of the device, it is said that a radius of curvature of approximately several hundred angstroms or less is required.
Further, in order to generate an electric field, it is necessary to dispose electrodes at close positions of about 1 μm or less and apply a voltage of several tens to several hundreds of volts. Further, in practice, thousands to tens of thousands of such elements are formed on the same substrate and are often used as an array connected in parallel. For this reason, the semiconductor device is generally manufactured by applying semiconductor fine processing technology.

One of the specific methods for manufacturing such a field emission cold cathode is the US SRI (Stanford).
Research Institute's Spindt (S
Pindt) et al. (J. App.
l. Phys. 39, p3504, 1968), a refractory metal such as molybdenum is deposited on a conductive substrate to obtain a sharp tip-shaped structure. This manufacturing method is shown in FIG. First, a silicon substrate 61 is prepared,
An oxide film is grown to form the insulating layer 62. Then, the gate layer 6
As No. 3, molybdenum is deposited by vacuum evaporation. Thereafter, an opening 6 having a diameter of about 1 μm is formed by photolithography.
13 is formed (FIG. 13)
(A)). Using the photoresist layer 65 as a mask, the gate layer 63 and the insulating layer 62 are etched (FIG. 13).
(B)). Next, after removing the photoresist layer 65, rotary oblique deposition is performed to form a sacrificial layer 64 of aluminum, and then molybdenum is vacuum-deposited in a vertical direction to deposit an emitter electrode 65 (FIG. 13C )).
Finally, the molybdenum film 67 deposited on the sacrificial layer 64
Is lifted off by selectively etching the sacrificial layer 64 to obtain a device structure (FIG. 13D).

[0004] The element thus manufactured is an emitter electrode 65.
By applying a voltage so that the gate layer 63 becomes positive, the silicon substrate 61
Electrons are emitted in a direction perpendicular to the direction. Such a structure is generally called a vertical field emission cold cathode. Applications of such devices include flat displays, micro vacuum tubes,
In addition, electron sources for electron tubes such as microwave tubes and cathode ray tubes have been proposed.

A field emission cold cathode is generally formed on a flat substrate. A technique for forming a field emission emitter on a curved substrate is disclosed in Japanese Patent Laid-Open No. 6-290702. This is because the substrate 71 has a curvature radius R as shown in FIG.
The insulating layer 72 and the gate layer 73 are laminated on the surface on the center side of the curvature, and a cavity 78 in which the emitter electrode 75 is to be formed is opened in the gate layer 73 and the insulating layer 72. I have. The center of curvature of such a substrate 0
Then, an evaporation source 79 is placed on the substrate 71 to deposit an emitter electrode 75 on the substrate 71. According to the manufacturing method of FIG. 14, since the emitter electrode material emitted from the evaporation source 79 is perpendicularly incident on the substrate, the emitter electrode 75 is formed perpendicularly to the substrate over the entire substrate to obtain an element with uniform characteristics. Can be.

[0006] Japanese Patent Application Laid-Open No. 4-249841 discloses FIG.
As shown in (1), a structure using a field emission cold cathode on a spherical surface for a flat display has been proposed. This is shown in FIG.
The substrate 81 has a spherical surface along the front glass 87 of the spherical display as shown in FIG.
3. Form the emitter electrode 85 and the like. By adopting such a structure, the envelope is made spherical so that it can withstand the pressure difference between the vacuum and the atmosphere, and the distance between the field emission cold cathode 89 and the front glass 87 on which the phosphor 86 is coated. Can be kept constant, and the display can be enlarged.

[0007]

Field emission cold cathodes are often used in an array in which a large number of field emission emitters are arranged on a plane and connected in parallel in order to extract a stable current. The trajectories of electrons emitted from the tip of each emitter electrode are distributed in a range of about 20 to 30 degrees in half angle,
The entire beam is wider than the electron emission area. When this is mounted on an electron tube and used as an electron beam source, it hinders beam focusing and improvement of current density.

As a thermionic source, a focused electron source called a Pierce electron gun has been proposed (JR Pier).
ce, “Theory and design of
electron beams ", 2nd ed.Va
n Nostrand, New York, 195
4). This electron source obtains a laminar electron beam 93 by forming a concentric spherical equipotential surface with an electron emitting surface 90 as shown in a sectional view including a focusing electrode 92 in FIG. However, since a hot cathode is used, a heater is required, and it takes several tens of seconds from the power and power supply to stable operation. Further, there is a problem that the material around the cathode is required to withstand a high temperature of about 700 to 1000 ° C. for a long time.

On the other hand, for a field emission cold cathode formed on a concave surface, a structure as shown in FIG. 14 is known, but in this case the purpose is to form a uniform emitter electrode 75 on the entire substrate, The center of curvature O is located at the evaporation source of the vapor deposition device. Considering that the field emission cold cathode is mounted on an electron tube, the size of the electron tube is several tens mm to 100 mm at most.
mm, and for the purpose of focusing individual radiated electron beams from a large number of field emission emitter groups as one electron beam bundle, the radius of curvature is equal to the size of the electron tube. It needs to be smaller. In this case, in order to adopt the method of FIG. 14, the evaporation source and the substrate must be arranged at positions of several tens mm to 100 mm. The distance between the evaporation source of a general vacuum evaporation apparatus and the substrate is several hundred mm. The high-melting point metal such as molybdenum used for the emitter electrode is deposited by electron beam evaporation using an electron gun, but it is difficult to perform electron beam evaporation when the distance between the evaporation source and the substrate is about 100 mm. is there. Further, even if possible, there is a problem that the substrate is exposed to a high temperature by radiant heat from an evaporation source of 2000 ° C. or higher. Although photolithography is used to form the cavity 78 for forming the emitter electrode 75, it is difficult to uniformly form a pattern of 1 μm or less on a substrate on a curved surface by a generally conceivable exposure technique. Also, FIG.
In the configuration of No. 4, it is possible to form a large number of emitter arrays on one substrate. However, assuming a case where the radius of curvature is 100 mm and the emitter array is arranged in a 4-inch wafer, the outer circumference and the center of the wafer are A height difference exceeding 10 mm occurs. Even if such a substrate can be realized, it is inefficient in terms of material yield, processing man-hours, management, and the like.

The idea of forming a field emission cold cathode on a spherical substrate 81 as shown in FIG.
9841, it is "extremely difficult to realize in terms of manufacturing process" as described in the publication.

An object of the present invention is to use a substrate on a flat surface to form an electron emission region into a curved surface by a process that can use conventional techniques such as film formation, photolithography, and etching, and an apparatus, and to form an electron beam. It is an object of the present invention to enable the manufacture of a field emission cold cathode capable of focusing.

[0012]

According to a method of manufacturing a field emission cold cathode of the present invention, after a structure of a field emission cold cathode is formed on a flat substrate in advance, an electron emission region and a surface layer of a substrate around the electron emission region are formed. The surface of the electron emission region is formed as a concave surface by forming a concave portion in the portion or transferring it onto a substrate having the concave portion formed thereon, bending the field emission cold cathode toward the concave portion, and fixing in that state. . Specifically, after forming a concave portion that penetrates the back surface and the substrate in advance, the concave portion is filled with a material that can be fluidized, and a flattened substrate is used. Are formed by fluidizing the liquid crystal, and the filling is hardened again to fix the structure of the field emission cold cathode. Note that a pressure difference can be used to bend the structure of the field emission cold cathode.

By forming the field emission cold cathode on a concave surface, the main component of electrons emitted from each emitter electrode faces the direction of converging to the center of curvature, and the equipotential surface of the gate electrode surface protrudes toward the cathode. Yes, focus the entire beam.

[0014]

Next, the present invention will be described with reference to the drawings. 1 to 4 are cross-sectional views schematically showing a first embodiment of the method for manufacturing a field emission cold cathode according to the present invention. As shown in FIG. 2, as a first process, processing of a substrate is performed. First, through holes 12 having a diameter larger than that of the emitter region are formed in the silicon substrate 11 at positions where the emitter region of each chip is to be formed by sandblasting or grinding. Here the hole diameter is 0.4
mmφ (FIG. 2B). Next, the through hole 12 is filled with a low-melting glass 13 having a softening point of about 500 ° C. and flowing at a temperature up to 600 ° C. (FIG. 2C). Subsequently, the surface 14 on the emitter formation side is polished and flattened (FIG. 2).
(D)). The temperature-viscosity characteristic of the low-melting glass 13 used here is such that when the field emission cold cathode is mounted on an electron tube or the like, it is exposed to a temperature of up to about 500 ° C. in a heating step such as degassing, sealing, and exhausting. At this time, it is determined in consideration of not being deformed again, and that at a temperature exceeding 600 ° C., a problem starts to occur in the heat resistance of the element itself.

In the second process, using the substrate thus processed, a field emission cold cathode is formed thereon such that the electron emission region 10 is located inside the region filled with the low melting point glass 13. (FIG. 2 (e)). The method is shown in FIG. First, the conductive layer 15 for supplying power to the emitter electrode
Molybdenum to 4000 angstroms (hereinafter referred to as
A is formed by vacuum evaporation. Insulating layer 1 on it
As 6000, silicon dioxide is deposited 8000A by CVD,
Further, molybdenum to be the gate layer 17 is formed by vacuum deposition at 2000A. Next, a diameter of 0.1 m inside the outer periphery of the through hole filled with the low melting point glass 13 formed earlier.
A photoresist layer (not shown) having an opening diameter of about 1 μm is formed by photolithography so that the region of m is the electron emission region 10. Using the opening as a mask, the gate layer 17 and the insulating layer 16 are etched by RIE (reactive ion etching) using carbon tetrafluoride or the like to form a cavity 18 for forming an emitter electrode (FIG. 4A )). Subsequently, aluminum is vacuum-deposited from an oblique direction while rotating the substrate to form a sacrificial layer 19. Further, molybdenum is vacuum-deposited from the front of the substrate to form the emitter electrode 20 (FIG. 4B). Finally, the sacrificial layer 19 is etched with phosphoric acid to remove the molybdenum film 21 on the gate. Assuming that the pitch of the cavities is 2 μm, a field emission cold cathode having an electron emission region in which about 2,000 emitter electrodes 20 are formed in a region of 0.1 mmφ is completed.

The electron emission region 10 formed in the second process has a positional relationship as shown in FIG. 1A with the previously formed through hole 12 filled with the low-melting glass 13.
In the third process, as shown in FIG. 3, the back surface of the substrate 11 is brought into close contact with the jig 22, and after evacuation, the temperature is reduced to a temperature at which the low-melting glass 13 flows in an atmosphere replaced with an inert gas such as argon. By heating, the jig 22 side is evacuated, and the low melting point glass 13 is sucked out to the back side of the substrate 11. This jig 2
Reference numeral 2 denotes a vacuum pump having a suction opening 23 at a position corresponding to the through hole 12 of the substrate 11 on the front surface side, and supporting the adhered substrate 11 on the front surface while being connected to the exhaust port 24 on the rear surface side. It is used to suck the low melting point glass 13 from the suction opening 23 (not shown). When a pressure difference of about 1.times.10@4 Pa is applied to both sides of the substrate, the heated low-melting glass 13 flows, and the electron emission region 10 has a depth of about 20 .mu.m at the center as shown in FIG. The electron-emitting region 10 and its vicinity have a substantially spherical cross-sectional shape. At this point, since a reaction layer is formed at the interface between the low melting point glass 13 and the conductive layer 15 filled in the through holes 12, when the temperature is lowered in this state, the low melting point glass solidifies, The discharge area 10 is fixed in a shape in which the bending has occurred. The amount of bending, that is, the curvature, can be controlled by the pressure difference between both surfaces of the substrate. However, the amount of bending (displacement) using laser light,
By applying feedback by measuring the tilt angle around the electron emission region, it is possible to control with high accuracy.

Here, the maximum amount of deflection is about 20 μm, but the total thickness of the conductive layer 15, the insulating layer 16, and the gate layer 17 is as thin as 1.4 μm, and the diameter of the through hole 12 is 0.4 mm.
(400 μm) and about 20 times the deflection, the degree of deformation is very small. Therefore, the structure of the field emission cold cathode formed in advance does not lose its function due to delamination between layers or the like. Finally, by cutting the substrate into individual chips, a number of field emission cold cathodes are completed.

When this field emission cold cathode is operated, the emission angle of the electrons emitted from each emitter electrode has a peak in the normal direction of the electron emission region 10, that is, in the focusing direction, and the electron emission is made. Due to the shape of the equipotential surface in the vicinity of the region, the entire electron beam is focused as shown in FIG. 1B and can be used as a high-density electron beam source that is narrowed down.

In the embodiment of the present invention, the back surface of the substrate is evacuated in order to deflect the electron emission region 10, but the same effect can be obtained by increasing the pressure on the front surface. Further, since the bent substrate receives a force that bends at the corner 24 of the through hole 12, the cross section of the through hole 12 on the substrate surface side is as follows.
Low melting point glass (not shown) as shown in FIGS. 5 (a) and 5 (b)
By filling in the shape of R or chamfered at the time of filling and polishing, damage to the periphery of the electron emission region can be prevented. Here, since the purpose is to focus the electron beam, the electron emission region is made concave, but depending on the application, the pressure difference may be reversed to make the electron emission region in FIG.
It is also possible to form the electron emission region in a convex shape as shown in FIG.

Although an example in which silicon is used as the substrate material has been described, if an electrode on the emitter electrode side is not taken out from the back surface of the substrate, an insulating ceramic material can be used as the substrate, and a low melting point can be used. Material selection for matching the thermal expansion coefficient with glass is facilitated. Further, the dimension setting of the electron emission region 10 and the through hole 12 is as follows.
The values are not limited to the values described above, and can be set arbitrarily according to desired characteristics.

FIGS. 6 and 7 are cross-sectional views schematically showing a method for manufacturing a field emission cold cathode according to a second embodiment of the present invention. In the embodiment of the first invention, a recess corresponding to the final shape of the electron emission region is formed on the substrate surface in the first process, and the electron emission region is bent along the recess in the third process. In this way, a method is adopted in which the cross-sectional shape of the electron emission region is set to a desired shape.

Details of the manufacturing method are as follows. First, on the surface side of the silicon substrate 11, as shown in FIG.
Is formed on the back side between the bottom of the recess 31 on the front side and the number 1
Exhaust holes 32 are formed by sandblasting while leaving a thickness of about 0 μm (FIG. 7A). Next, the recess 31 and the exhaust hole 32 are made to penetrate from the substrate surface side by photolithography and etching (FIG. 7B). Subsequently, as in the first embodiment, the portion from the concave portion 31 on the front surface side to the exhaust hole 32 is filled with the low-melting glass 13 flowing at a softening point of about 500 ° C. and up to 600 ° C. (FIG. 7 ( c)). Subsequently, the surface on the emitter formation side is polished and flattened (FIG. 7).
(D)). The concave portion shown in FIG. 7A is processed so as to control the diameter on the polished surface in consideration of the polishing margin at this time. Here, the diameter is 0.4 mm.

In the second process, using the substrate thus processed, in the same manner as in the first embodiment of the present invention,
A field emission cold cathode having a diameter of 0.1 mm is formed thereon such that the electron emission region is located inside the region filled with the low melting point glass.

The electron emission region 10 formed by the second process has a positional relationship as shown in FIG. 8A with the concave portion 31 formed with the low melting point glass 13 previously formed. In the third process, as in the first embodiment, when a pressure difference is applied to both surfaces of the substrate, the electron emission region 1
0 is a concave portion 31 formed in advance as shown in FIG.
Bends along the cross-sectional shape of. When the temperature is lowered in this state, the electron emission region 10 is fixed along the shape of the recess 31. In this way, it is possible to control the cross section of the electron emission surface 10 with good reproducibility.

FIGS. 9 and 10 are sectional views schematically showing a third embodiment of the method for manufacturing a field emission cold cathode according to the present invention. In this embodiment, first, a structure of a field emission cold cathode is formed on a temporary substrate in a first process, and a second process is performed.
In the above process, the surface layer of the field emission cold cathode is separated from the temporary substrate, and positioned and fixed on the substrate having the concave surface.

The details of the manufacturing method are as follows. First
In the process (1), first, magnesium oxide (MgO) is formed as a release layer 42 on a temporary substrate 41 by vacuum deposition at 2000A. Next, 5000 A of gold is formed as the bonding layer 43, and molybdenum to be the conductive layer 15 for supplying power to the emitter electrode is formed by vacuum evaporation of 4000 A. On top of this, 8000 A of silicon dioxide is deposited as an insulating layer 16 by CVD, and molybdenum to be the gate layer 17 is deposited at 2000 A.
The film is formed by vacuum evaporation. Next, a photoresist layer (not shown) having an opening diameter of about 1 μm is formed by photolithography so that a region having a diameter of 0.1 mm is set as an electron emission region. By RIE (reactive ion etching) using carbon tetrafluoride or the like with this opening as a mask,
The gate layer 17 and the insulating layer 16 are etched to form a cavity 18 for forming an emitter electrode.
(A)). Subsequently, magnesium oxide is vacuum-deposited from an oblique direction while rotating the substrate to form a sacrificial layer 44. When molybdenum is vacuum-deposited from the front of the substrate to form the emitter electrode 20, the structure of the field emission cold cathode is completed on the temporary substrate 41 (FIG. 9B).

In the second process, the molybdenum film 21 on the gate is removed by etching the MgO of the sacrificial layer 44 and the release layer 42 with acetic acid, and the structure 45 of the field emission cold cathode is separated from the temporary substrate 41. (FIG. 9C).
The structure 45 of the field emission cold cathode is fixed to a substrate. A silicon wafer is used as the substrate 46 in FIG.
The one processed into the shape of (b) is used. The processing method is
This is the same as the first process of the embodiment of the second invention. The concave portion 31 of the substrate 46 and the electron emission region 10 of the field emission cold cathode structure 45 are formed at the same interval in advance, and the field emission cold cathode structure 45 is formed on the surface side of the substrate 46 as shown in FIG. The electron emission region 10 and the concave portion 31 are aligned with each other so that the bonding layer 43 on the back surface side of the electron emission region comes into contact.
This work is preferably performed in pure water continuously after the cleaning after etching. After removing water, heat treatment is performed at a temperature of about 450 ° C. while depressurizing the back surface of the substrate. When the gold of the bonding layer 43 and the silicon of the substrate form a eutectic, the structure 45 of the field emission cold cathode becomes The electron emission region 10 fixed to the surface of the substrate 46 becomes concave (FIG. 10B). According to the embodiment of the present invention, the steps of embedding and polishing the low melting point glass as in the first and second embodiments of the present invention are unnecessary.

FIGS. 11 and 12 are cross sectional views schematically showing a fourth embodiment of the method for manufacturing a field emission cold cathode according to the present invention. In this embodiment, a method is adopted in which a field emission cold cathode chip having a thinned substrate is mounted on a base having a curved surface to make the electron emission region concave.

First, in a first process, a silicon substrate 51
Is prepared, and a thermal oxide film is grown to form an insulating layer 52. Subsequently, molybdenum is deposited as a gate layer 53 by vacuum evaporation. After that, the diameter of about 1 μm is obtained by photolithography so that the area having a diameter of 0.1 mm is used as an electron emission area.
A photoresist layer (not shown) having an opening is formed. Using this photoresist layer as a mask, the gate layer 5
3 and the insulating layer 52 are etched by RIE (reactive ion etching) using carbon tetrafluoride or the like (FIG. 11).
(A)). Next, after removing the photoresist layer, rotary oblique deposition is performed to form a sacrificial layer 54 of aluminum,
Subsequently, molybdenum is vacuum-deposited from the vertical direction to deposit the emitter electrode 20 (FIG. 11B). further,
The molybdenum film 21 deposited on the sacrificial layer 54 is lifted off by selectively etching the sacrificial layer 54 to obtain a device structure (FIG. 11C).

FIG. 12A is an enlarged cross-sectional view showing one field emission cold cathode chip manufactured in this way, in which an electron emission region 10 is formed at the center on the front surface side. . Next, in the second process, the back surface of the substrate 51 is ground to a thickness of 20 μm by grinding (FIG. 12).
(B)). Then, after dicing into individual chips at the cutting positions 59, the chips are mounted on a curved base 55. The base is made of stainless steel or Kovar having a chip mounting surface 56 processed into a desired curved surface, and is a part of a device on which a field emission cold cathode is mounted.
Suction hole 57 is provided on the surface and the thickness is about 5000A.
Gold plated. When the field emission cold cathode 58 is placed on the chip mounting surface 56 of the base 55 and heat-treated at a temperature of about 450 ° C. while being sucked from a suction hole 57 by a vacuum pump (not shown), the surface of the chip mounting surface 56 The gold-plated gold and the substrate of the field emission cathode 58 form a eutectic of silicon, and the field emission cold cathode 58 is fixed in a bent shape along the cross-sectional shape of the chip mounting surface 56 of the base 55. Is done.

In the embodiment of the present invention, a method of obtaining a curved surface shape when mounted on a device has been described. However, a curved surface is formed on another part in advance, and the field emission cold cathode 58 is fixed to the surface. After obtaining the curved surface shape, a method of mounting the device on a device may be adopted.

[0032]

As described above, according to the present invention,
The field emission cold cathode, which has a concave electron emission area and can obtain the focusing effect of the electron beam, without developing a special device,
It can be manufactured in large quantities and easily using conventional high-precision exposure technology using a flat substrate and ordinary film forming technology and etching technology such as electron beam evaporation.
Therefore, a high-current-density cold cathode can be provided at low cost as an electron source for various electron tubes and electron beam devices.

[Brief description of drawings]

FIGS. 1A to 1C are partial cross-sectional views illustrating a third process of manufacturing a field emission cold cathode according to an embodiment of the present invention.

FIGS. 2A to 2E are partial cross-sectional views illustrating a first process of manufacturing a field emission cold cathode according to the first embodiment of the present invention.

FIG. 3 is a partial cross-sectional view illustrating a jig used in a third process of manufacturing the field emission cold cathode according to the first embodiment of the present invention.

FIGS. 4A to 4C are partial cross-sectional views illustrating a second process of manufacturing the field emission cold cathode according to the first embodiment of the present invention.

FIGS. 5A and 5B are partial cross-sectional views illustrating a modification of the cross-sectional shape of the substrate used in the first embodiment of the present invention.

FIG. 6 is a perspective view illustrating a method of forming a concave portion in a first process of a manufacturing process of a field emission cold cathode according to a second embodiment of the present invention.

FIGS. 7A to 7D are partial cross-sectional views illustrating a first process of the field emission cold cathode according to the second embodiment of the present invention.

8A and 8B are partial cross-sectional views illustrating a third process of manufacturing the field emission cold cathode according to the embodiment of the second invention.

FIGS. 9A to 9C are partial cross-sectional views illustrating a first process of manufacturing a field emission cold cathode according to the third embodiment of the present invention.

FIGS. 10A and 10B are partial cross-sectional views illustrating a second process of manufacturing the field emission cold cathode according to the third embodiment of the present invention.

FIGS. 11A to 11C are partial cross-sectional views illustrating a first process of manufacturing a field emission cold cathode according to a fourth embodiment of the present invention.

FIGS. 12A to 12C are partial cross-sectional views illustrating a second process of manufacturing the field emission cold cathode according to the fourth embodiment of the present invention.

13 (a) to 13 (d) are partial cross-sectional views showing steps of manufacturing a field emission cold cathode according to a conventional example.

FIG. 14 is disclosed in JP-A-6-290702.
FIG. 3 is a partial cross-sectional view illustrating a method of forming a field emission emitter on a curved substrate.

FIG. 15 is disclosed in JP-A-4-249841.
FIG. 2 is a partial cross-sectional view illustrating a display using a spherical field emission cathode.

FIG. 16 is a partial cross-sectional view illustrating a Pierce electron gun, which is a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Electron emission area 11, 51 Silicon substrate 12 Through hole 13 Low melting glass 15 Conductive layer 16, 52 Insulating layer 17, 53 Gate layer 18 Cavity 19 Sacrificial layer 20 Emitter electrode 22 Jig 30 Grinding grindstone 31 Depression 32 Exhaust hole 41 Temporary Substrate 42 Release layer 43 Bonding layer 44 Sacrificial layer 45 Field emission cold cathode structure 46 Substrate 55 Base 56 Chip mounting surface 57 Suction hole

Claims (6)

[Claims] 1. A conductive substrate, or a conductive layer laminated on a conductive or insulating substrate, and an insulating layer and a conductive gate layer deposited on the conductive layer, and a cavity formed in the insulating layer and the gate layer. In a method of manufacturing a field emission cold cathode having a plurality of electron emission regions, the field emission emitter including a sharp-edged substantially conical emitter electrode provided at A method for manufacturing a field emission cold cathode, characterized in that after the structure of the cold cathode is formed, the electron emission region is bent and fixed in this state, whereby the electron emission region has a curved cross-sectional shape. 2. The method for manufacturing a field emission cold cathode according to claim 1, wherein after forming the structure of the field emission cold cathode on a planar substrate having a conductive layer laminated on a conductive or insulating substrate, the electron emission region is formed. And forming a concave portion on the surface of the substrate below the conductive layer in the periphery thereof, and bending the electron emission region toward the concave portion. 3. The method for manufacturing a field emission cold cathode according to claim 1, wherein a part or the whole of the field emission cold cathode formed in advance on the flat substrate is separated and formed on another substrate having a concave portion of a desired shape. Alternatively, a method for manufacturing a field emission cold cathode, comprising fixing the same on a concave portion of the same substrate. 4. The method for manufacturing a field emission cold cathode according to claim 2, wherein after forming a recess penetrating the back surface of the substrate in advance, the recess is filled with a material capable of being fluidized and the substrate is flattened. Then, after forming the structure of the field emission cold cathode, the recess is formed by fluidizing the filling material, and the filling material is cured again to fix the structure of the emission cold cathode. Production method. 5. The method of manufacturing a field emission cold cathode according to claim 4, wherein the cross section of the concave portion has a desired shape, and the structure of the field emission cold cathode is made to conform to this shape. Manufacturing method of cathode. 6. The method for manufacturing a field emission cold cathode according to claim 1, wherein the structure of the field emission cold cathode is deflected by a pressure difference between the front side and the back side of the field emission cold cathode. A method for producing a field emission cold cathode, comprising: