JPH09129121A - Electron emitting element and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify a structure and simplify the manufacturing process for application to a flat panel display. SOLUTION: A three-layer structural body pinched with an insulating layer 53 between a lower electrode layer 52 and an upper electrode layer 54 is arranged on a glass substrate 51, and an electron emitting film 55 having an electron emitting function via excitation is formed on the side face section of the three-layer structural body. When the electric field is applied between the electrodes 52, 54, surface conduction type electron emission occurs from the surface of the electron emitting film 55, and electrons fly to an opposite substrate 20. If the thickness of the insulating layer 53 is accurately controlled at the time of manufacture, the thickness of the insulating layer 53 can be unified for each element, and the field intensity applied to the electron emitting film 55 can be unified. When this element is arranged in the matrix state on the glass substrate 51, the lower electrode layer 52 and the upper electrode layer 54 can be utilized as driving wiring layers as they are.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron-emitting device, and more particularly, to a surface conduction electron-emitting device.

[0002]

2. Description of the Related Art As a kind of flat panel display, FED (Field Emission Display) has been energetically studied. In this FED, a cathode substrate and an anode substrate are opposed to each other, a number of electron-emitting devices are arranged on the cathode substrate, electrons are emitted from the electron-emitting devices toward the anode substrate, and a phosphor layer on the anode substrate is formed. It emits light. The electron-emitting devices formed on the cathode substrate correspond to individual pixels. The electron-emitting devices used so far generally have a sharp projection structure suitable for electron emission. For example, an electron-emitting device made of a conical metal with a sharp tip is widely used. I have.

On the other hand, in recent years, surface conduction electron-emitting devices have been receiving attention. This is an electron-emitting device utilizing a phenomenon in which an electron is emitted when a current flows through a thin film having a small area formed on a substrate in parallel with the film surface.
Such an electron emission phenomenon was described in 1965 in “Radio Engineering Electrophysics (Radio Eng.
Electron. Phys.) Volume 10, 1290-1296 "
Since then, by MI Elinson et al., Various reports have been made to date. Specifically, this surface conduction type electron emission phenomenon has been reported for SnO ₂ (Sb) thin film developed by Erinson et al., Au thin film, ITO thin film, carbon thin film and the like.

Further, recently, Japanese Patent Publication No. 6-101297
Japanese Patent Application Laid-Open No. 6-87392 discloses a technology for forming this surface conduction type electron-emitting device using an insulating layer sandwiching a surface in which fine particles are dispersed. There is disclosed a method of manufacturing an electron-emitting device having a surface conduction electron-emitting function by applying electric heating to a conductor film.

[0005]

As described above, a surface conduction electron-emitting device is expected to be used for a flat panel display such as an FED, and when applied to such a display, It is necessary to arrange a large number of devices in a matrix on a substrate so that electron emission from each device can be controlled independently. The first problem to be solved when driving a large number of electron-emitting devices arranged in a matrix in this way is to make the characteristics of the individual devices uniform. That is, in the conventional surface conduction electron-emitting device, an electron-emitting film having a small area is formed on the substrate, and electrodes for supplying current are formed on both sides of this electron-emitting film. Then, an electric current flows through the film surface of the electron emission film existing between the pair of electrodes to cause electron emission. Therefore, if the distance between both electrodes varies from element to element, the characteristics of each element become non-uniform. In other words, even if the same voltage is applied, the amount of emitted electrons differs for each element. In this way, if the characteristics of the electron-emitting devices that make up one flat panel display are non-uniform, the display state of the screen becomes uneven, and a high-quality display can no longer be realized. For this reason, high accuracy is required for the interval between the electrodes forming each electron-emitting device. However, in order to secure such high position accuracy, a high level alignment technique is required, and the manufacturing cost cannot help rising.

The second problem for application to a display is to simplify the wiring required for driving as much as possible. As described above, in order to independently control a large number of electron-emitting devices arranged in rows and columns, wiring is provided on the substrate in a vertical and horizontal direction, and by controlling voltages to these wirings, individual It must be possible to control the electron emission from the device. However, in order to provide such wiring to the conventional electron-emitting device,
It is necessary to form a considerably complicated three-dimensional wiring layer on the substrate, and the manufacturing process is inevitably complicated. For this reason, the production cost also rises.

Therefore, an object of the present invention is to provide an electron-emitting device capable of simplifying the manufacturing process by simplifying the entire structure as much as possible even when a large number of devices are arranged and used on the same substrate. To do.

[0008]

[Means for Solving the Problems]

(1) A first aspect of the present invention is an electron-emitting device,
An electron-emitting device having a function of arranging a three-layer structure in which an insulating layer is sandwiched between a lower electrode layer and an upper electrode layer on a substrate, and emitting electrons by energizing the side surfaces of the three-layer structure. A film is formed.

(2) The second aspect of the present invention is the above-mentioned first aspect.
In the electron-emitting device according to the aspect, the side surface of the three-layer structure has a flat surface that forms a predetermined angle with the substrate so that the end surface of the lower electrode layer, the end surface of the insulating layer, and the end surface of the upper electrode layer are aligned. It is designed to be formed.

(3) A third aspect of the present invention is the above-mentioned first aspect.
In the electron-emitting device according to the aspect (1), the side surface of the three-layer structure has three steps so that the upper end surface of the lower electrode layer is exposed and the upper end surface of the insulating layer is exposed. It is the one.

(4) The fourth aspect of the present invention is the above-mentioned first aspect.
In the electron-emitting device according to the aspect of 1, the side surface portion of the three-layer structure has a two-step staircase so that the upper end surface of the lower electrode layer is exposed and the end surface of the insulating layer and the end surface of the upper electrode layer are aligned. It is a shape.

(5) A fifth aspect of the present invention relates to the above-mentioned first aspect.
In the electron-emitting device according to the aspect, the side surface portion of the three-layer structure has a two-stepped shape so that the end surface of the lower electrode layer and the end surface of the insulating layer are aligned and the end surface of the insulating layer is exposed. It is designed to

(6) The sixth aspect of the present invention is the above-mentioned first aspect.
In the electron-emitting device according to the fifth aspect, the end face forming the electron-emitting film of a part or the whole layer of the three-layer structure is inclined with respect to the substrate.

(7) A seventh aspect of the present invention is the above-mentioned first aspect.
~ In the electron-emitting device according to the sixth aspect, by arranging a plurality of lower electrode layers extending in the column direction in the row direction and arranging a plurality of upper electrode layers extending in the row direction in the column direction, Form multiple partitions arranged in a matrix,
At the intersection of the lower electrode layer and the upper electrode layer, an insulating layer is sandwiched between both electrode layers to form a three-layer structure, an electron emission film is formed on the side surface of each three-layer structure, and each section is independent. The electron emission film is formed.

(8) An eighth aspect of the present invention relates to the above-mentioned first aspect.
~ In the method of manufacturing an electron-emitting device according to the seventh aspect, the first preparation layer is formed on the insulating substrate, and the first preparation layer is formed.
Forming a lower electrode layer by patterning the preparation layer of, forming an insulating intermediate layer on the substrate and the lower electrode layer, and forming a second preparation layer on the intermediate layer;
Patterning the second preparation layer to form an upper electrode layer; patterning an intermediate layer to form an insulating layer; and a side surface of a three-layer structure including a lower electrode layer, an insulating layer, and an upper electrode layer. And a step of forming an electron emission film on the portion.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on an embodiment shown in the drawings.

§1. The structure of the conventional electron-emitting device and
Operating Principle First, the structure and operating principle of a conventional general surface conduction electron-emitting device will be described. FIG. 1 is a cross-sectional view showing the structure of a conventional surface conduction electron-emitting device 10 and a counter substrate 20. In this example, the electron-emitting device 10
Is formed by forming electrodes 12 and 13 on a glass substrate 11 and further forming an electron emission film 14 thereon. The electron emission film 14 functions as a cathode electrode, and for example, SnO ₂ , In ₂ O ₃ , Pb is used.
Any material, such as a metal oxide such as O, a metal such as Au and Ag, carbon, and various semiconductors, may be used as long as the material has a known surface conduction electron emission phenomenon. On the other hand, the counter substrate 20 is formed by forming a transparent electrode 22 and a phosphor layer 23 on a glass substrate 21. The transparent electrode 22 is made of, for example, a material such as ITO and functions as an anode electrode.

FIG. 2 is a top view of the components formed on the glass substrate 11 in the electron-emitting device 10 shown in FIG. 1, and the cross section taken along the section line 1-1 in this figure is shown in FIG. It will be. The state in which the electrodes 12 and 13 face each other at a predetermined interval and the electron emission film 14 is formed therebetween is clearly shown.

Now, let us consider the phenomenon that occurs when wiring is provided to each part as shown in FIG. According to this wiring, the electrode 13 is grounded, and a negative voltage is applied to the electrode 12 from the power supply 31. The cathode / anode voltage is also applied between the electron-emitting device 10 and the counter substrate 20 by the power source 32. In the state shown in FIG. 1, however, the switch 33 is open, so that the voltage is not applied. I haven't been. Now, when a voltage is applied to both sides of the electron emission film 14 by the electrodes 12 and 13, electron emission occurs as shown by arrows in the figure on the surface of the electron emission film 14. This is a phenomenon known as surface conduction electron emission.

Here, the switch 33 is closed and the cathode /
When the voltage between the anodes is applied, the electrons emitted to the surface of the electron emission film 14 will fly to the counter substrate 20 on the anode side, as shown in FIG. The collision of electrons toward each other causes the phosphor layer 23 to emit fluorescence. Here, for convenience of explanation, only the components for one pixel are shown.
By arranging components for pixels in a matrix in a matrix, a flat panel display in which pixels are arranged on a two-dimensional plane can be realized. In such a flat panel display, it is general that the switch 33 is kept closed and the voltage applied from the power source 31 is adjusted for each pixel to control the light emitting state of each pixel. More specifically, by adjusting the value of the voltage applied to the electron emission film 14 and the application time, it is possible to control the amount of electrons flying to the counter substrate 20 side.

As described above, the technical problems in manufacturing a flat panel display using the electron-emitting device 10 are to make the characteristics of individual devices uniform and to simplify the driving wiring. Is. The variation in characteristics of each element mainly depends on the dimensional accuracy. FIG. 4 is a diagram showing the dimensions of the main part of the electron-emitting device 10. In the case of a general flat panel display, the dimensions of each part shown here are, for example, D1 = 15 μm and D2 = 80.
The values are of the order of μm, D3 = 0.2 μm, D4 = 0.5 μm (of course, these numerical values are shown as an example, and specific numerical values differ depending on individual displays). Of these dimensions, the dimension that particularly affects the device characteristics is the distance D between the electrodes 12 and 13.
It is one. The distance D1 governs the electric field strength applied to the electron emission film 14, and if the distance D1 changes, the amount of emitted electrons also changes. Therefore, in order to realize a display having uniform display characteristics over the entire surface, it is necessary to make the dimensions D1 of the individual electron-emitting devices arranged on the glass substrate 11 uniform. Therefore, in the actual manufacturing process, for example, D1 =
A predetermined dimensional accuracy of 15 μm ± 2 μm is required, and a highly accurate patterning process is required. This causes a rise in manufacturing cost, which is a major obstacle to practical use. Particularly, in the future, the demand for low-power drive type displays tends to increase more and more, and the absolute value of the interval D1 has to be set smaller and smaller.
It is expected that higher dimensional accuracy will be required.

Further, the problem of simplifying the drive wiring is
This is a difficult problem to solve in the electron-emitting device having the conventional structure. In FIGS. 1 and 3, the wiring for the electron-emitting device for one pixel is shown. However, when it is used for a display, it is provided for each of a large number of electron-emitting devices arranged vertically and horizontally on the glass substrate 11. Independent wiring is applied,
The voltage applied to the electron emission film 14 must be controlled independently for each electron emission element. In order to provide such wiring on the glass substrate 11, many patterning processes are required, and the manufacturing process must be complicated. This is also one of the factors that increase the manufacturing cost, and is an obstacle to practical use.

§2. The structure and structure of the electron-emitting device of the present invention
In accordance with the conventional structure, the electron emission film 14 is formed as a film parallel to the glass substrate 11. This is a very general method to meet the demand of "forming a thin film on a substrate". On the other hand, the structure of the present invention is characterized in that the electron emission film 14 is formed at a predetermined angle with respect to the glass substrate 11 (for example, formed vertically).

Now, on the substrate (not shown in FIG. 5),
A three-layer structure as shown in the perspective view of FIG. 5 (a) is prepared.
This three-layer structure is a structure in which an insulating layer 53 is sandwiched between a lower electrode layer 52 and an upper electrode layer 54, and has a so-called "sandwich structure". After preparing such a three-layer structure, an electron emission film 55 having a function of emitting electrons by energization is formed on the side surface of the three-layer structure.
The structure shown in the perspective view of (b) is obtained. Such a structure will function as the electron-emitting device 50. That is, as compared with the conventional electron-emitting device 10 shown in FIG. 3, the lower electrode layer 52 functions as the electrode 13, the upper electrode layer 54 functions as the electrode 12, and the electron-emitting film 55 emits electrons. The function as the film 14 will be fulfilled. Further, the insulating layer 53 plays a role as a spacer for maintaining the accuracy of the distance between the electrode 12 and the electrode 13.

In the drawings of the present application, even in the perspective view,
Hatching is given to each component as needed, and it shows. This hatching is not for showing a cross section, but for facilitating identification of individual components.

Now, with respect to the electron-emitting device 50 having such a structure, let us consider a phenomenon that occurs when wiring is provided in each part as shown in FIG. According to this wiring, the lower electrode layer 52 is grounded, and a negative voltage is applied to the upper electrode layer 54 from the power supply 31. Further, the cathode / anode voltage is also applied between the electron-emitting device 50 and the counter substrate 20 by the power supply 32, but in the state shown in FIG. 6, the switch 33 is open, so that the voltage is not applied. I haven't been. Now, when a voltage is applied to both sides of the electron emission film 55 by the lower electrode layer 52 and the upper electrode layer 54, electron emission as indicated by an arrow in the figure occurs on the film surface portion of the electron emission film 55. That is, a surface conduction electron emission phenomenon occurs.

Here, the switch 33 is closed and the cathode /
When the voltage between the anodes is applied, the electrons emitted to the surface of the electron emission film 55 fly to the counter substrate 20 on the anode side, as shown in FIG. 7, and from such a cathode to the anode. The collision of electrons toward each other causes the phosphor layer 23 to emit fluorescence. Here, for the sake of convenience of description, only one pixel component is shown.
By arranging components for pixels in a matrix in a matrix, a flat panel display in which pixels are arranged on a two-dimensional plane can be realized. In practice, as in the conventional flat panel display using electron-emitting devices, the voltage applied from the power supply 31 is adjusted for each pixel while the switch 33 remains closed to change the light emission state for each pixel. Can be controlled.

In the example shown here, as shown in FIG. 6, by applying a negative voltage to the upper electrode layer 54 side,
On the surface of the electron emission film 55, a flow of electrons from the upper side to the lower side is formed, but conversely, by applying a negative voltage to the lower electrode layer 52 side, the electron emission film 5 is formed.
Even if a flow of electrons from the lower side to the upper side is formed on the surface of 5, the electron emission to the counter substrate 20 side is performed without any trouble. Therefore, the polarity of the applied voltage between the lower electrode layer 52 and the upper electrode layer 54 does not matter.

FIG. 8 is a diagram showing the dimensions of the main part of the electron-emitting device 50. Here, the thickness D of the insulating layer 53
1 is, practically, D1 = 0.1 μm to 1 mm,
More preferably, it is set to about 1 μm to 100 μm. Further, as the thicknesses D2 and D3 of the lower electrode layer 52 and the upper electrode layer 54, D2 and D3 = 0.0 in practical use.
1 μm to 1 mm, more preferably 1 μm to 30 μ
It is better to set it to about m. The width D4 of the three-layer structure may be arbitrary in consideration of the operation of electron emission, but since the three-layer structure itself acts as a capacitive element, the parasitic capacitance value of the element itself is suppressed to a low value and the response speed is reduced. It is preferable to make it as small as possible in order to improve
It is preferable to set D4 = about 10 μm to 100 μm.
Further, the thickness D5 of the electron emission film 55 needs to be a thickness at which a surface conduction type electron emission phenomenon occurs, and it is desirable that the thickness D5 is as thin as possible for efficient electron emission. Practically, it is preferable to set D5 = about 0.01 μm to 1 μm.

When the structure of the present invention shown in FIG. 8 is compared with the conventional structure shown in FIG. 4, the dimension D1 which is the distance between the electrodes 12 and 13 in the conventional structure is the insulating layer 53 of the present invention. It can be seen that this corresponds to the thickness D1. That is, each dimension D1 corresponds to the distance between the pair of electrodes for applying an electric field to the electron emission film, and the dimension D1 determines the electric field strength applied to the electron emission film. In order to realize a display with uniform display characteristics,
As described above, it is necessary to make the dimension D1 uniform for each electron-emitting device arranged on the glass substrate. Here, focusing on the accuracy of the dimension D1, in the conventional structure shown in FIG. 4, the accuracy is in the plane direction parallel to the substrate surface, whereas in the structure of the present invention shown in FIG. It can be seen that the accuracy is in the thickness direction. That is, if the conventional structure shown in FIG. 4 is called a "horizontal structure" and the structure of the present invention shown in FIG. 8 is called a "vertical structure", the accuracy of the dimension D1 is flat in the case of the "horizontal structure". While it is necessary to ensure the accuracy in the direction, in the case of the "vertical structure", the accuracy of the dimension D1 should be ensured as the accuracy in the thickness direction.

Generally, in a manufacturing process such as a semiconductor planar process for forming layers on a substrate, it is easier to secure dimensional accuracy in the thickness direction than to secure dimensional accuracy in the plane direction. In other words, as shown in FIG. 4, comparing the step of forming the electrodes 12 and 13 having an accurate predetermined distance D1 with the step of forming the insulating layer 53 having an accurate predetermined thickness D1 , If the dimension values D1 are the same, the latter process is easier than the former process. In particular, in recent years, the film forming technique on the substrate has made great progress, and it is possible to control the thickness with considerable accuracy. Therefore, the electron-emitting device having the structure of the present invention has an easier manufacturing process than the electron-emitting device having the conventional structure.
The merit of reducing the manufacturing cost can be obtained.

§3. Another implementation of the electron-emitting device of the present invention
In the three-layer structure shown in FIGS. 5 (a) and 5 (b), the lower electrode layer 5
The end faces of No. 2, the end face of the insulating layer 53, and the end face of the upper electrode layer 54 are aligned, and the side surface portion of the three-layer structure forms a flat surface substantially perpendicular to the substrate. The electron emission film 55 is formed on this flat surface, and the electron emission film 55 is formed.
The film surface of is almost vertical to the substrate.

On the other hand, FIG. 9 shows another embodiment. In this embodiment, first, a three-layer structure as shown in FIG. 9A is prepared on a substrate (not shown). In this three-layer structure, the upper surface of the end portion of the lower electrode layer 62 is exposed,
In addition, the side surface portion of the three-layer structure has a three-step stepped shape so that the upper surface of the end portion of the insulating layer 63 is exposed. As shown in FIG. 9B, an electron emission film 65 is formed on the side surface of such a three-layer structure. In the electron-emitting device 60 having such a structure, the electron-emitting film 65 is formed along the steps of the end portion of the three-layer structure, but the lower electrode layer 62 and the upper electrode layer 64 are formed. This is the same as the electron-emitting device 50 according to the above-described embodiment in that a surface-conduction type electron emission phenomenon occurs based on the electric field between and.

FIG. 10A is a perspective view of an electron-emitting device 70 according to another embodiment. This electron-emitting device 70
Prepares a three-layer structure in which the side surface has a two-step staircase so that the upper end surface of the lower electrode layer 72 is exposed and the end surface of the insulating layer 73 is aligned with the end surface of the upper electrode layer 74. Then, the electron emission film 75 is formed on the side surface of this three-layer structure. On the other hand, FIG. 10B is a perspective view of an electron-emitting device 80 according to another embodiment. This electron-emitting device 80
Then, the upper electrode layer 84 is formed so that the end surface of the lower electrode layer 82 and the end surface of the insulating layer 83 are aligned, and the upper surface of the end portion of the insulating layer 83 is exposed. It has a two-step step shape, and the electron emission film 8 is formed on this side surface.
5 are formed.

10C to 10E are sectional views of an electron-emitting device 70 according to another embodiment. 10 (c) is a modification of the element 60 shown in FIG. 9 (b), and FIG. 10 (d) is shown in FIG.
A modified example of the element 70 shown in (a), FIG. 10 (e) is shown in FIG. 10 (b).
It is a modification of the element 80 shown in FIG. In each of these modified examples, the end surface of each layer forms an inclined surface with respect to the substrate.

As described above, the side surface portion of the three-layer structure does not necessarily have to be a flat surface, and may have a step shape. Further, the end faces of each layer do not necessarily have to be perpendicular to the substrate, and may be inclined faces. However, in order to achieve the purpose of ensuring high dimensional accuracy by determining the distance between the lower electrode layer and the upper electrode layer by the thickness of the insulating layer sandwiched between them, the embodiment shown in FIG. 5 is most suitable. preferable.

§4. Embodiments Applied to Displays Although the structure for a single electron-emitting device has been described above, the electron-emitting device of the present invention is particularly suitable for flat panel display applications. In this case, a large number of electron-emitting devices are used by arranging them vertically and horizontally on a substrate. Hereinafter, such an embodiment will be described.

FIG. 11 is a perspective view showing a state in which four electron-emitting devices 200 are formed on the glass substrate 100.
When applied to a display, one electron-emitting device
Since the display operation for the pixels is performed, in the example shown in FIG. 11, the display for a total of 2 × 2 pixels can be performed. Of course, in an actual display, a larger number of electron-emitting devices will be arranged. In addition, in the perspective view of FIG. 11, the hatching given to each component is not for showing a cross section as mentioned above,
This is to make it easy to identify individual components. The structure of the electron-emitting device shown in FIG. 11 is as follows.

First, a plurality of lower electrode layers 110 extending in the column direction are arranged in the row direction on the glass substrate 100 (in this example, 2
Book) Place. On the other hand, the upper electrode layer 130 extending in the row direction
Are arranged in the column direction (two in this example). Thus, the lower electrode layer 110 extending in the column direction and the upper electrode layer 130 extending in the row direction form a plurality of sections arranged in a matrix on the glass substrate 100 (each electrode layer). Is a black line on the board, each square surrounded by this black line forms one section). Here, the lower electrode layer 110
An insulating layer 120 is formed between both electrode layers at the intersection of the upper electrode layer 130 and the upper electrode layer 130. That is, the lower electrode layer 110, the insulating layer 120, and the upper electrode layer 13 are provided at each intersection.
This means that a three-layer structure of 0 is constructed. The electron emission film 1 is formed on the side surface of each three-layer structure.
40 is formed, and the individual electron emission films 140 are independent in each section.

With this structure, the electron-emitting devices 200 can be formed independently for each section. In the structure shown in FIG. 11, the side surface of the three-layer structure is a flat surface, but as described in §3,
The side surface portion may have a stepped shape or an inclined surface.

Now, the important point here is that the lower electrode layer 11 is
0 and the upper electrode layer 130 are formed on the glass substrate 10 respectively.
That is, it can also function as a wiring layer that extends vertically and horizontally on 0. As described above, in order to use the display as a display, it is necessary to provide wiring for individually controlling electron emission for each electron-emitting device arranged in a matrix. In the case of the conventional "horizontal structure" electron-emitting device, it is necessary to separately prepare a layer for such wiring, so that the structure on the substrate becomes very complicated. On the other hand, in the case of the "vertical structure" electron-emitting device of the present invention,
Since the lower electrode layer 110 and the upper electrode layer 130 fulfill the function of wiring, it is not necessary to separately provide a wiring layer. That is, according to the electron-emitting device of the present invention, the problem of simplifying the wiring required for driving can be achieved.

FIG. 12 is a diagram for explaining the driving principle of the electron-emitting device according to the present invention (hatching indicates FIG. 1).
1 for showing the correspondence with each component). Here, an example in which 5 rows and 5 columns, that is, a total of 25 electron-emitting devices 200 are formed is shown. That is, five lower electrode layers 110 extending in the column direction are arranged in the row direction, and five upper electrode layers 130 extending in the row direction are arranged in the column direction, forming 25 sections. Has been done. Electron emitting devices 200 that are independent of each other are formed in the respective compartments, and the electron emission from each electron emitting device 200 is
Each can be controlled independently.

In order to perform such control, the selector 1
50 and a driver 160 are provided. The selector 150 is one of the five lower electrode layers 110.
Performs the function of selecting a book and grounding it. On the other hand, driver 1
60 has a function of giving a predetermined voltage signal to each of the five upper electrode layers 130. Selector 150 is 5
If the operation of sequentially selecting the lower electrode layer 110 of the book is performed,
It becomes possible to access the five columns sequentially by time division. Then, according to the signal supplied from the driver 160,
Electron emission from the electron-emitting devices 200 belonging to the column currently being accessed is controlled. For example, as shown in the figure, in a state where the selector 150 selects the first column and is grounded, the driver 160 causes the upper electrode layer 130 of the first row to pass through.
If a negative voltage is applied to the electron-emitting device in the first row and the first column, the wiring shown in FIG. 7 is formed, and the electron emission to the counter substrate 20 occurs.
Such a driving method is a so-called "simple matrix driving".

As described above, according to the present invention, since the lower electrode layer 110 and the upper electrode layer 130 can be used as they are as a wiring layer, the structure is very simple even when applied to a display, and the manufacturing process is simplified. The process is also simplified and the manufacturing cost can be reduced.

§5. When applied to a display
The forming step Finally, an example of a manufacturing process for obtaining the structure shown in FIG. 11 will be described with reference to the perspective view shown in FIGS. 13 to 19. In these perspective views as well, hatching for clarifying the correspondence with each component shown in FIG. 11 will be applied.

First, as shown in FIG. 13, the glass substrate 1
A first preparation layer 115 having conductivity is formed on the entire surface of the substrate 00 (which may be any insulating substrate) by using a general film forming method such as a vacuum evaporation method or a sputtering method. Subsequently, the first preparatory layer 115 is patterned to form the pattern shown in FIG.
As shown in FIG. 4, the lower electrode layer 110 is formed. For patterning the first preparation layer 115, general photolithography and etching techniques may be used.
However, as the first preparation layer 115, it is not always necessary to use a layer having conductivity at that time. For example, a metal particle-dispersed resist (so-called metal paste) obtained by dispersing metal fine particles in a photosensitive resin is applied on the glass substrate 100 to form a photosensitive paste layer, and this paste layer is As the preparatory layer 115 of No. 1, the paste layer is exposed and developed by a photolithography method to perform patterning, and finally, a baking process is performed to remove the resin component in the paste layer to obtain conductivity. The lower electrode layer 110 can be obtained. The photosensitive paste layer may be formed of an organic metal mixed resist which is a mixture of a photosensitive resin and an organic metal.

Subsequently, an insulating intermediate layer 125 is formed on the entire surface of the glass substrate 100 and the lower electrode layer 110, as shown in FIG. Further, as shown in FIG. 16, a second preparation layer 135 is formed on this intermediate layer 125.
As the second preparation layer 135, the first preparation layer 115
Similarly to the above, a conductive layer may be used, or the above-mentioned photosensitive paste layer may be used. Then, patterning is performed on the second preparation layer 135 (general photolithography and etching methods may be used. When the paste layer is used, further firing is performed), and as shown in FIG. The upper electrode layer 130 having the above is formed.

Next, by patterning the intermediate layer 125, the insulating layer 120 can be formed as shown in FIG. Thus, a three-layer structure including the lower electrode layer 110, the insulating layer 120, and the upper electrode layer 130 can be formed. Therefore, finally, by forming the electron emission film 140 on the side surface of the three-layer structure, the electron emission device according to the present invention can be obtained as shown in FIG. In the step of forming the electron emission film 140, for example, a solvent in which a material that causes a surface conduction electron emission phenomenon is dissolved in an organic solvent is prepared, and the solvent is applied and dried on the side surface portion of the three-layer structure. You can take various methods.

[0049]

【Example】

<Example of Material> As the material of each part of the structure shown in FIG. 5, the following materials are preferably used.

Lower electrode layer 52 and upper electrode layer 54: Any conductive material can be used as long as it functions as an electrode, but is required to have withstand voltage, heat resistance, workability, corrosion resistance and specific resistance. It is preferable to select an appropriate material in consideration. Specifically, Al, Ni, Pd, Pb, Pt, W, Mo, C
It is preferable to use a metal material such as r, Ti, Cu, Au, and Ag.

Insulating layer 53: In particular, it is preferable to use a material having low surface conductivity, specifically, quartz glass, Si.
It is preferable to use O ₂ , Si ₃ N _4, or the like.

Electron emission film 55: Any material may be used as long as it is a material known to have a surface conduction electron emission phenomenon. Metal oxides such as SnO ₂ , In ₂ O ₃ and PbO, metals such as Au and Ag, carbon and various semiconductors are generally known materials. In addition, for example, as disclosed in Japanese Patent Publication No. 6-87392, a thin-film conductor film containing fine particles is heated by energization, and the thin-film conductor film is locally broken, deformed or altered by Joule heat. Then, the electron emission film can be formed by bringing the state into an electrically high resistance state.
Alternatively, the electron emission film may be formed by a gas deposition method as disclosed in the publication.

<Example of Manufacturing Method of Electron-Emitting Element> A Cr layer having a thickness of 3 μm is deposited by a sputtering method on a clean quartz glass substrate having a thickness of 3 mm (FIG. 13). In addition, a resist agent (ORM8 manufactured by Tokyo Ohka Kogyo Co., Ltd.
5 ”) is spin coated with a spinner and then 80
Allow to dry for 30 minutes at ° C. After air cooling, a desired pattern is exposed, the resist is developed and washed with water, and then left in an oven at 135 ° C for 30 minutes. After air cooling, Cr is developed using a Cr etching solution (“MR-DS” manufactured by Tokyo Ohka Kogyo Co., Ltd.) and washed with water.

Next, the substrate was left for 5 minutes in a resist stripping solution kept at 120 ° C. (“Clean Stop” manufactured by Tokyo Ohka Kogyo Co., Ltd.), and then in a strip rinse solution at room temperature for 1 minute and isopropyl alcohol at room temperature. The resist is peeled off by immersing each in 1 minute. This substrate is washed with water and then dried. Through the above steps, patterning of the lower electrode layer 110 is completed (FIG. 14).

Subsequently, the film thickness is 20 μm by the sputtering method.
Of SiO ₂ is deposited (FIG. 15), and a Cr layer having a film thickness of 3 μm is deposited thereon by a sputtering method (FIG. 16).
On top of that, a resist agent (“OR manufactured by Tokyo Ohka Kogyo Co., Ltd.
M85 ") is spin-coated with a spinner and left to dry in an oven at 80 ° C for 30 minutes. After air cooling, a desired pattern is exposed, the resist is developed and washed with water, and then left in an oven at 135 ° C for 30 minutes. After air cooling, Cr
Etching solution ("MR-D" manufactured by Tokyo Ohka Kogyo Co., Ltd.
S ") is used to develop Cr and wash with water.

Next, the substrate was left for 5 minutes in a resist stripping solution (“Clean Stop” manufactured by Tokyo Ohka Kogyo Co., Ltd.) kept at 120 ° C., and then in a strip rinse solution at room temperature for 1 minute and isopropyl alcohol at room temperature. The resist is peeled off by immersing each in 1 minute. This substrate is washed with water and then dried. Through the above steps, the patterning of the upper electrode layer 130 is completed (FIG. 17).

Subsequently, a resist agent ("ORM85" manufactured by Tokyo Ohka Kogyo Co., Ltd.) is spin-coated on this with a spinner, and left to dry in an oven at 80 ° C for 30 minutes. After air cooling, a desired pattern is exposed, the resist is developed and washed with water, and then left in an oven at 135 ° C for 30 minutes. After air cooling, the intermediate layer 125 is patterned by immersing it in a hydrofluoric acid aqueous solution kept at room temperature for 10 minutes.

Next, the substrate was left for 5 minutes in a resist stripping solution (“Clean Stop” manufactured by Tokyo Ohka Kogyo Co., Ltd.) kept at 120 ° C., and then in a strip rinse solution at room temperature for 1 minute and isopropyl alcohol at room temperature. The resist is peeled off by immersing each in 1 minute. This substrate is washed with water and then dried. Through the above steps, the insulating layer 12
The patterning of 0 is completed (FIG. 18).

Furthermore, an organic solvent containing an organopalladium compound (“CATA PASTE CC manufactured by Okuno Chemical Industries Co., Ltd.
P ”) is printed at a desired position (side surface portion of the three-layer structure) by a screen printing method and left for 15 minutes to form a thin film on the side surface portion. After that, it is baked at about 200 ° C for 20 minutes,
An electron emission film 140 containing fine particles of
9).

<Example of Manufacturing Method of Counter Substrate> An ITO layer having a thickness of 1 μm is deposited on a clean quartz glass substrate having a thickness of 3 mm by a sputtering method. A phosphor layer made of ZnO: Zn having a film thickness of 20 μm was vapor-deposited thereon by an EB vapor deposition method to fabricate a counter substrate 20.

<Example of Electron Emitting Operation> 10
The cathode / anode voltage between the counter substrate and the electron-emitting device was held by keeping the electron-emitting device manufactured in the above-mentioned example and the counter substrate in parallel at a distance of 3 mm in a vacuum chamber kept at ⁻¹⁰ Pa. Was applied as 5 kV. As the operating voltage of the electron-emitting device, when the upper electrode layer was kept at the ground potential and 20 V was applied to the lower electrode layer, electrons were emitted toward the counter substrate, and good light emission characteristics were obtained. Further, when a large number of electron-emitting devices arranged in a matrix were driven by a simple matrix and a signal corresponding to predetermined image information was given, image formation was observed on the counter substrate.

[0062]

As described above, according to the present invention, since the electron-emitting device is constituted by the vertical structure, the dimensional accuracy can be easily ensured and the device electrode can be used also as the wiring. Even when a large number of substrates are arranged on the same substrate, the entire structure is simplified and the manufacturing process can be simplified.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing the structure of a conventional surface conduction electron-emitting device 10 and a counter substrate 20.

2 is a top view of components formed on a glass substrate 11 in the electron-emitting device 10 shown in FIG. 1, and a cross section taken along a cutting line 1-1 in this figure is shown in FIG.

3 is a cross-sectional view showing a state where electrons are being emitted from an electron-emitting device 10 shown in FIG.

FIG. 4 is a diagram showing dimensions of a main part of the electron-emitting device 10 shown in FIG.

FIG. 5 is a perspective view showing a structure of an electron-emitting device 50 according to an embodiment of the present invention.

6 is a cross-sectional view showing wiring for the electron-emitting device 50 shown in FIG.

7 is a cross-sectional view showing a state where electrons are being emitted from the electron-emitting device 50 shown in FIG.

8 is a diagram showing dimensions of a main part of the electron-emitting device 50 shown in FIG.

FIG. 9 is an electron emission device 60 according to another embodiment of the present invention.
It is a perspective view which shows the structure of.

FIG. 10 is a perspective view and a sectional view showing the structure of an electron-emitting device according to still another embodiment of the present invention.

FIG. 11 is a perspective view showing a state in which four electron-emitting devices of the present invention are formed on a glass substrate 100.

FIG. 12 is a plan view for explaining the driving principle of the electron-emitting device according to the present invention.

13 is a perspective view showing a first stage of a manufacturing process for obtaining the structure shown in FIG.

14 is a perspective view showing a second stage of the manufacturing process for obtaining the structure shown in FIG. 11. FIG.

15 is a perspective view showing a third stage of the manufacturing process for obtaining the structure shown in FIG. 11. FIG.

16 is a perspective view showing a fourth step of the manufacturing process for obtaining the structure shown in FIG.

17 is a perspective view showing a fifth step of the manufacturing process for obtaining the structure shown in FIG. 11. FIG.

18 is a perspective view showing a sixth stage of the manufacturing process for obtaining the structure shown in FIG. 11. FIG.

FIG. 19 is a perspective view showing the final stage of a manufacturing process for obtaining the structure shown in FIG. 11.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Electron emission element 11 ... Glass substrate 12 ... Electrode 13 ... Electrode 14 ... Electron emission film 20 ... Counter substrate 21 ... Glass substrate 22 ... Transparent electrode 23 ... Phosphor layer 31 ... Power supply 32 ... Power supply 33 ... Switch 50 ... Electron emission Element 51 ... Glass substrate 52 ... Lower electrode layer 53 ... Insulating layer 54 ... Upper electrode layer 55 ... Electron emitting film 60 ... Electron emitting element 62 ... Lower electrode layer 63 ... Insulating layer 64 ... Upper electrode layer 65 ... Electron emitting film 70 ... Electron emitting element 72 ... Lower electrode layer 73 ... Insulating layer 74 ... Upper electrode layer 75 ... Electron emitting film 80 ... Electron emitting element 82 ... Lower electrode layer 83 ... Insulating layer 84 ... Upper electrode layer 85 ... Electron emitting film 100 ... Glass substrate 110 ... Lower electrode layer 115 ... First preparation layer 120 ... Insulating layer 125 ... Intermediate layer 130 ... Upper electrode layer 135 ... Second preparation layer 140 ... Electron emission film 150 ... Selector 160 ... Driver 200 ... dimensions of the electron-emitting devices D1 to D5 ... each part

Claims (8)

[Claims] 1. A function of arranging a three-layer structure, in which an insulating layer is sandwiched between a lower electrode layer and an upper electrode layer, on a substrate, and emitting electrons by energizing the side surface of the three-layer structure. An electron-emitting device characterized in that an electron-emitting film having the above is formed. 2. The electron-emitting device according to claim 1, wherein the side surface portion of the three-layer structure is aligned with the substrate so that the end surface of the lower electrode layer, the end surface of the insulating layer, and the end surface of the upper electrode layer are aligned. An electron-emitting device characterized by forming a flat surface having a predetermined angle. 3. The electron-emitting device according to claim 1, wherein the side surface portion of the three-layer structure is formed so that the upper end surface of the lower electrode layer is exposed and the upper end surface of the insulating layer is exposed. An electron-emitting device characterized by having a step-like shape. 4. The electron-emitting device according to claim 1, wherein the upper surface of the end portion of the lower electrode layer is exposed, and the end surface of the insulating layer is aligned with the end surface of the upper electrode layer. An electron-emitting device characterized in that its side surface has a two-step step shape. 5. The electron-emitting device according to claim 1, wherein the end surface of the lower electrode layer is aligned with the end surface of the insulating layer, and
An electron-emitting device characterized in that a side surface portion of a three-layer structure has a two-stepped shape so that an upper surface of an end portion of an insulating layer is exposed. 6. The electron-emitting device according to claim 1, wherein an end face forming an electron-emitting film of some or all layers of the three-layer structure forms an inclined surface with respect to the substrate. An electron-emitting device characterized by the above. 7. The electron-emitting device according to claim 1, wherein a plurality of lower electrode layers extending in the column direction are arranged in the row direction, and an upper electrode layer extending in the row direction is arranged in the column direction. By arranging a plurality of sections, a plurality of sections arranged in a matrix are formed on the substrate, and an insulating layer is sandwiched between both electrode layers at the intersection of the lower electrode layer and the upper electrode layer to form a three-layer structure. An electron-emitting device characterized in that an electron-emitting film is formed on a side surface of each three-layer structure, and an independent electron-emitting film is formed for each section. 8. A method for manufacturing an electron-emitting device according to claim 1, wherein a first preparation layer is formed on an insulating substrate, and the first preparation layer is patterned. To form a lower electrode layer, forming an insulating intermediate layer on the substrate and the lower electrode layer, and forming a second preparation layer on the intermediate layer; Patterning a preparation layer to form an upper electrode layer; patterning the intermediate layer to form an insulating layer; and a three-layer structure including the lower electrode layer, the insulating layer, and the upper electrode layer. And a step of forming an electron emission film on a side surface of the electron emission device.