JP2003016924A - Field emission type electron source - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a field emission type electron source applicable to a device required to reduce angular distribution in an electron emitting direction like an electron source of a high precision display. SOLUTION: A strong electric field drift layer 6 is composed of drift parts 6a formed of a plurality of oxidized porous polycrystal silicon layers formed at the intersecting parts of lower electrodes 12a and surface electrodes 7, and separation parts 6b formed of polycrystal silicon layers which fill spaces between the drift parts 6a. Barrier ribs 13 are provided for limiting broadening of electron beams emitted from each electron source element 10a, between one surface side of an insulating substrate 11 and a face plate 30 arranged opposedly to the insulating substrate 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a field emission electron source adapted to emit an electron beam by field emission.

[0002]

2. Description of the Related Art Conventionally, a field emission electron source in which a strong electric field drift layer made of an oxidized or nitrided porous semiconductor layer is formed on one surface side of a conductive substrate and a surface electrode is formed on the strong electric field drift layer. Have been proposed (for example, JP-A-8-250766, JP-A-9-259795, JP-A-10-326557, and JP-2966).
842, Japanese Patent No. 2987140, etc.).

As a field emission type electron source of this type, for example, one having a structure shown in FIG. 7 is known. In the field emission electron source 10 'having the configuration shown in FIG. 7, a strong electric field drift layer 6 made of an oxidized porous polycrystalline silicon layer is formed on the main surface side of an n-type silicon substrate 1 which is a conductive substrate, A surface electrode 7 made of a metal thin film is formed on the drift layer 6, and an ohmic electrode 2 is formed on the back surface of the n-type silicon substrate 1. In the example shown in FIG. 7, the non-doped polycrystalline silicon layer 3 is interposed between the n-type silicon substrate 1 and the strong electric field drift layer 6, but the n-type polycrystalline silicon layer 3 is not interposed. A configuration in which the strong electric field drift layer 6 is formed on the silicon substrate 1 has also been proposed.

A field emission type electron source 10 'having the structure shown in FIG.
In order to emit electrons from the surface electrode 7, a collector electrode 21 arranged opposite to the surface electrode 7 is provided, and the surface electrode 7 is placed in a vacuum state between the surface electrode 7 and the collector electrode 21. A DC voltage Vps is applied between the surface electrode 7 and the n-type silicon substrate 1 so that the electrode 2) is on the higher potential side (positive electrode), and the collector electrode 2
A DC voltage Vc is applied between the collector electrode 21 and the surface electrode 7 so that 1 is on the high potential side with respect to the surface electrode 7. If the direct current voltages Vps and Vc are set appropriately, the electrons injected from the n-type silicon substrate 1 will not be affected by the strong electric field drift layer 6.
And is emitted through the surface electrode 7 (note that the chain line in FIG. 7 is the electron e emitted through the surface electrode 7).
^-Shows the flow). A material having a small work function (for example, gold) is used for the surface electrode 7, and the film thickness of the surface electrode 7 is 10
It is set to about 15 nm to 15 nm.

A field emission type electron source 1 having the above-mentioned structure.
At 0 ′, the current flowing between the surface electrode 7 and the ohmic electrode 2 is called the diode current Ips, and the collector electrode 21
Current flowing between the front surface electrode 7 and the front surface electrode 7 (that is, the front surface electrode 7
The emission current (emission electron current) Ie is referred to as the emission current Ie (see FIG. 7).
The larger the ratio of e (= Ie / Ips), the higher the electron emission efficiency. In this field emission electron source 10, a DC voltage Vps applied between the surface electrode 7 and the ohmic electrode 2 is applied.
Can emit electrons even at a low voltage of about 10 to 20 V, and the emission current Ie increases as the DC voltage Vps increases.

In this field emission type electron source 10 ', the electron emission characteristics (emission current, electron emission efficiency, etc.) have a low degree of vacuum dependency, and the popping phenomenon does not occur during electron emission, and stable electron emission is achieved. It can be released with efficiency.

In the above-mentioned field emission electron source 10 ', the strong electric field drift layer 6 is an n-type silicon substrate 1 which is a conductive substrate.
After depositing a non-doped polycrystalline silicon layer on the
The polycrystalline silicon layer is formed by making it porous by anodizing and oxidizing the porous polycrystalline silicon layer (porous polycrystalline silicon layer) at a temperature of, for example, 900 ° C. by a rapid heating method. There is.

As shown in FIG. 8, the strong electric field drift layer 6 formed as described above has at least a columnar polycrystalline silicon grain (semiconductor crystal) 51 and a thin layer formed on the surface of the grain 51. Silicon oxide film 52, nanometer-order silicon microcrystals 63 interposed between grains 51, and silicon that is an oxide film formed on the surface of silicon microcrystals 63 and having a film thickness smaller than the crystal grain size of the silicon microcrystals 63. It is considered to be composed of the oxide film 64. That is, in the strong electric field drift layer 6, it is considered that the surface of each grain contained in the polycrystalline silicon layer before the anodic oxidation treatment is made porous and the crystal state is maintained in the central portion of each grain. . Therefore, most of the electric field applied to the strong electric field drift layer 6 is concentratedly applied to the silicon oxide film 64, and the injected electrons are accelerated by the strong electric field applied to the silicon oxide film 64, and are transferred to the surface between the grains 51. Since it drifts toward the direction of the arrow in FIG. 8 (upward in FIG. 8), the electron emission efficiency can be improved. Here, in the field emission type electron source 10 ′ having such a strong electric field drift layer 6, the heat generated in the strong electric field drift layer 6 is radiated through the grains 51, so that the popping phenomenon at the time of electron emission is prevented. It is considered to have been done. The electrons that have reached the surface of the strong electric field drift layer 6 are considered to be hot electrons, and easily tunnel through the surface electrode 7 and are emitted into a vacuum.

In the above-mentioned field emission electron source 10 ', an n-type silicon substrate is used as a conductive substrate, but as shown in FIG. 9, a conductive material is formed on one surface of an insulating substrate 11' made of a glass substrate. A field emission type electron source 10 ″ using the one in which the conductive layer 12 is formed is also proposed. Here, FIG.
The same components as those of the field emission electron source 10 ′ shown in FIG.

A field emission electron source 10 "having the structure shown in FIG.
In order to emit electrons from the surface electrode 7, a collector electrode 21 arranged opposite to the surface electrode 7 is provided, and a vacuum is applied between the surface electrode 7 and the collector electrode 21. Surface electrode 7 so that it is on the high potential side (positive electrode)
DC voltage Vps is applied between the collector electrode 21 and the surface electrode 7 while the DC voltage Vps is applied between the collector electrode 21 and the surface electrode 7 so that the collector electrode 21 is on the higher potential side than the surface electrode 7. To do. If the DC voltages Vps and Vc are appropriately set, the electrons injected from the conductive layer 12 drift in the strong electric field drift layer 6 and are emitted through the surface electrode 7 (note that the chain line in FIG. 9 indicates the surface electrode). 7 electrons e emitted through ^-. showing the flow of) the field emission electron source 10 'having the above configuration, the current flowing between the surface electrode 7 and the conductive layer 12 is called the diode current Ips, collector The current flowing between the electrode 21 and the surface electrode 7 (that is,
If the electron current emitted through the surface electrode 7 is called the emission current (emitted electron current) Ie (see FIG. 9), the ratio of the emission current Ie to the diode current Ips (= Ie / Ips) is large. The higher the electron emission efficiency, the higher. In addition, this field emission type electron source 10 "
Then, electrons can be emitted even when the DC voltage Vps applied between the surface electrode 7 and the conductive layer 12 is a low voltage of about 10 to 20 V, and the emission current Ie increases as the DC voltage Vps increases.

The field emission type electron source 1 shown in FIG.
When 0 ”is applied as the electron source of the display,
For example, the configuration shown in FIG. 10 may be adopted.

The display shown in FIG. 10 has a frame between a rear plate (not shown) made of a flat glass substrate to which the field emission electron source 10 is adhered and a face plate 30 made of the flat glass substrate. A space between the rear plate and the face plate is maintained in vacuum by interposing a support spacer (not shown) in the shape of a circle.
A collector electrode (transparent electrode) made of an ITO film is formed on the surface of the face plate 30 facing the field emission electron source 10, and pixels 31 as shown in FIG. 11 are provided. There is. Here, the pixel 31 has three primary colors R.I. Three G and B phosphor cells 32a, 32b, 32c are formed by coating, and the phosphor cells 32a, 32a, between each pixel 31 and in each pixel 31 are formed.
32b and 32c are separated by a separation layer 33 having a black pattern called a black stripe.

The field emission type electron source 10 shown in FIG.
Insulating substrate 11 'made of glass substrate and insulating substrate 1
1 ', a lower electrode 12a made of a plurality of conductive layers arranged on one surface, and a drift portion 6a made of a plurality of oxidized porous polycrystalline silicon layers formed so as to overlap the lower electrode 12a and a drift. A strong electric field drift layer 6 having a separation portion 6b made of a polycrystalline silicon layer filling the spaces between the portions 6a, and a plurality of surface electrodes 7 formed on the strong electric field drift layer 6 in a direction intersecting the lower electrode 12a. Is equipped with.

In this field emission electron source 10, a plurality of lower electrodes 12a are arranged in a row on one surface of the insulating substrate 11.
And the drift portion 6a of the strong electric field drift layer 6 is sandwiched between the surface electrode 7 and the plurality of surface electrodes 7 formed on the strong electric field drift layer 6, a pair of the surface electrode 7 and the lower electrode 12a is appropriately selected. Then, by applying voltage between the selected pairs,
The strong electric field acts only on the drift portion 6a at the portion corresponding to the intersection of the selected surface electrode 7 and the lower electrode 12a, and electrons are emitted. That is, it is equivalent to disposing the electron source element 10a including the surface electrode 7, the lower electrode 12a, and the drift portion 6a at a lattice point of a matrix (lattice) including the surface electrode 7 and the lower electrode 12a, and applying a voltage. Electrons can be emitted from a desired electron source element 10a by selecting a set of the front surface electrode 7 and the lower electrode 12a to be operated. Each electron source element 10a has one phosphor cell 32.
It is formed for each individual sub-pixel consisting of a, 32b and 32c. That is, in the thickness direction of the insulating substrate 11 ′, one sub-pixel is arranged so as to overlap with one electron source element 10 a.

The drift portion 6a is considered to have the same structure as that shown in FIG. That is, the drift unit 6
a is at least a columnar polycrystalline silicon grain (semiconductor crystal) 51, a thin silicon oxide film 52 formed on the surface of the grain 51, a nanometer-order silicon microcrystal 63 interposed between the grains 51, and silicon. It is considered to be composed of a silicon oxide film 64 which is an oxide film formed on the surface of the microcrystal 63 and having a film thickness smaller than the crystal grain size of the silicon microcrystal 63.

By the way, in the above display, the airtight space surrounded by the face plate 30, the rear plate and the supporting spacers is kept in a vacuum state. Three
In order to prevent 0 and the rear plate from contacting each other, a reinforcing spacer (not shown) is interposed between the field emission electron source 10 and the face plate 30 in addition to the supporting spacer.

[0017]

By the way, in the electron source used for a high-definition display, it is required to shorten the distance between the pixels 31 and the distance between the sub-pixels, but the electron emission from the electron source element 10a is required. If the angular distribution in the directions becomes large, there is a problem that color mixing occurs and color shift occurs, and necessary colors are not displayed.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a device that requires a small angular distribution in the electron emission direction, such as an electron source of a high-definition display. It is to provide a field emission type electron source which can be applied.

[0019]

In order to achieve the above object, the invention of claim 1 comprises an insulating substrate, and a plurality of electron source elements formed on one surface side of the insulating substrate to emit electrons.
The insulating substrate is provided with a partition wall for limiting the spread of the electron beam emitted from the electron source element between the face plate arranged to face the insulating substrate on one surface side of the insulating substrate. Since the spread of the electron beam emitted from the source element is limited by the partition wall, there is little variation in the emission direction of the electron beam, and the spread of the emitted electron beam is small. It can be applied to a device that requires a small angular distribution in the electron emission direction.

According to a second aspect of the present invention, in the first aspect of the present invention, the electron source element includes a lower electrode formed on the one surface side of the insulating substrate, and an electron source element on the one surface side in the thickness direction of the insulating substrate. A surface electrode facing the lower electrode, and a drift portion formed of an oxidized, nitrided, or oxynitrided porous semiconductor layer interposed between the lower electrode and the surface electrode, and the surface electrode between the surface electrode and the lower electrode. Electrons injected from the lower electrode drift through the drift electrode and are emitted through the surface electrode due to the electric field that acts on the drift portion when a voltage is applied with the high potential side as the emission source of the electron beam emitted from the electron source element. Since the directions are easily aligned with the normal direction of the surface electrode and the angular distribution of the electron emission direction is relatively small, increase the screen brightness when used as the electron source of the display. It can be.

According to a third aspect of the present invention, in the first or second aspect of the present invention, a plurality of electron source elements are respectively arranged at positions corresponding to lattice points of the matrix, and a plurality of partition walls are provided. Since the cross section orthogonal to the thickness direction of the insulating substrate is formed in a straight line, it is possible to prevent the spread of electrons from overlapping between the electron source elements arranged with the partition wall interposed therebetween. When used as a light source, electrons can be prevented from reaching subpixels corresponding to electron source elements adjacent to each other in the juxtaposed direction of R, G, and B subpixels, and color shift due to color mixing can be prevented. be able to.

According to a fourth aspect of the present invention, in the first or second aspect of the invention, the partition wall is formed in a mesh shape in a cross section orthogonal to the thickness direction of the insulating substrate, and an electron is formed in the mesh shape. Since the source elements are arranged one by one, the spread of the electron beam emitted from each electron source element by disposing one electron source element in the mesh of the mesh-shaped partition wall Is limited over the entire circumference, and when used as an electron source of a full-color display, the electrons emitted from each electron source element have sub-pixels and columns corresponding to electron source elements adjacent in the row direction. Since it can be prevented that the sub-pixels corresponding to the electron source elements adjacent to each other in the direction are reached, color shift due to color mixture can be prevented.

According to a fifth aspect of the invention, in the first or second aspect of the invention, a plurality of electron source elements are arranged at positions corresponding to the lattice points of the matrix, and a plurality of partition walls are provided, and each partition wall is provided. Has a part that restricts the spread of the electron beam in the row direction of the matrix and a part that restricts the spread of the electron beam in the column direction. Therefore, when used as an electron source of a full-color display, the electrons emitted from each electron source element Since it is possible to prevent the sub-pixels corresponding to the adjacent electron source elements and the sub-pixels corresponding to the adjacent electron source elements in the column direction from being reached, it is possible to prevent color shift due to color mixing.

According to a sixth aspect of the invention, in the third or fifth aspect of the invention, at least one of the plurality of partition walls also serves as a spacer for keeping a prescribed distance between the insulating substrate and the face plate. The step of positioning and arranging a reinforcing spacer, which is separate from the insulating substrate, with respect to the insulating substrate is unnecessary, and when used as an electron source of a display, the assembly process is simplified.

According to a seventh aspect of the present invention, in the invention of the fourth aspect, the partition wall is an insulating substrate so that a part of a mesh-like mesh portion keeps a predetermined distance between the insulating substrate and the face plate. Since it is extended in the thickness direction of the base plate, the partition wall has a function as a reinforcing spacer for keeping the distance between the insulating substrate and the face plate at a specified distance. The step of positioning and arranging the spacer for use with the insulating substrate is unnecessary, and the assembly step is simplified when used as the electron source of the display.

According to an eighth aspect of the invention, in the first to seventh aspects of the invention, the partition wall is made of ceramic,
As compared with the case where the partition wall is formed of glass, the partition wall can be easily manufactured and the mechanical strength of the partition wall can be increased.

According to a ninth aspect of the invention, in the first to eighth aspects of the invention, since the partition wall and the insulating substrate are integrally formed, the step of disposing the partition wall with respect to the insulating substrate is unnecessary. , Can reduce the production cost.

According to a tenth aspect of the present invention, in the first to seventh aspects of the present invention, the partition wall is formed integrally with the face plate. Therefore, when the partition wall is used as an electron source of a display, the partition wall is to the face plate. Since the process of positioning and arranging is not required, the assembly process can be simplified,
The production cost can be reduced.

[0029]

BEST MODE FOR CARRYING OUT THE INVENTION (Embodiment 1) Hereinafter, a display using the field emission electron source of this embodiment will be exemplified.

In the display having the structure shown in FIG. 1, a field emission electron source 10 and a face plate 30 made of a flat glass substrate are arranged to face each other. Although not shown, a collector electrode (transparent electrode) made of an ITO film is formed on the surface of the face plate 30 facing the field emission electron source 10 and the collector electrode is used as the field emission electron source 10. A plurality of pixels (pixels) are formed on the opposite surface of the. Here, one pixel is provided with three sub-pixels composed of R, G, and B phosphor cells.

In the field emission electron source 10, a strong electric field drift layer 6 is laminated on one surface side of an insulating substrate 11 having a plurality of lower electrodes 12a arranged on one surface side. A plurality of front surface electrodes 7 formed in a direction orthogonal to the lower electrode 12a are provided on the surface 6. That is, the lower electrode 12 a and the surface electrode 7 are arranged so as to be orthogonal to each other with the strong electric field drift layer 6 interposed therebetween. Here, the strong electric field drift layer 6 includes a drift portion 6a formed of a plurality of oxidized porous polycrystalline silicon layers formed at respective intersecting portions of the plurality of lower electrodes 12a and the plurality of surface electrodes 7, The drift portion 6a is filled with a separation portion 6b made of a polycrystalline silicon layer. The lower electrode 12a is embedded in the insulating substrate 11 with the surface on the one surface side of the insulating substrate 11 exposed, and the one surface of the insulating substrate 11 and the surface of the lower electrode 12a are Are on the same plane. The lower electrode 12a is formed in a strip shape, and the pads 27 are formed on both ends in the longitudinal direction. The surface electrode 7 is formed in a strip shape and is connected to the pads 28 at both ends in the longitudinal direction.

In this field emission electron source 10, a plurality of lower electrodes 12a arranged in a line on one surface side of the insulating substrate 11 are arranged.
, And the plurality of surface electrodes 7 formed on the strong electric field drift layer 6, the drift portion 6a of the strong electric field drift layer 6 is sandwiched between the surface electrode 7 and the lower electrode 12a. By applying a voltage between the selected and selected pairs, a strong electric field acts only on the drift portion 6a at the portion corresponding to the intersection of the selected surface electrode 7 and the lower electrode 12a, and electrons are emitted. That is, the surface electrode 7 and the lower electrode 12
This corresponds to disposing the electron source element 10a including the surface electrode 7, the lower electrode 12a, and the drift portion 6a at the lattice point of the matrix (lattice) including a, and the surface electrode 7 and the lower electrode 12a to which a voltage is applied. It becomes possible to emit electrons from a desired electron source element 10a by selecting the combination of Here, the drift portion 6a is considered to have the same configuration as that of FIG. 8 described above. That is, the drift portion 6a includes at least a columnar polycrystalline silicon grain (semiconductor crystal) 51, a thin silicon oxide film 52 formed on the surface of the grain 51, and nanometer-order silicon microcrystals interposed between the grains 51. 6
3 and a silicon oxide film 64 which is an insulating film formed on the surface of the silicon microcrystal 63 and having a film thickness smaller than the crystal grain size of the silicon microcrystal 63.
Here, it is considered that each grain 51 is formed along the thickness direction of the insulating substrate 11. In the electron source element 10a described above, the emission direction of the electron beam emitted through the front surface electrode 7 is easily aligned with the normal direction of the front surface electrode 7, so that it is not necessary to provide a complicated shadow mask or electron converging lens, and the display is thin. Can be realized. In addition, the surface electrode 7
The voltage applied between the lower electrode 12a and the lower electrode 12a
Since the electrons can be emitted even at a low voltage, the power consumption can be reduced.

By the way, in this embodiment, as the above-mentioned insulating substrate 11, the one having the structure as shown in FIGS. 2 and 3 is used. That is, in the present embodiment, as the insulating substrate 11, the spread of the electron beam emitted from each electron source element 10a between the insulating substrate 11 and the face plate 30 that is arranged to face the insulating substrate 11 at a distance. A ceramic substrate integrally formed with a plurality of partition walls 13 for limiting the above is used. Here, the partition wall 13 is formed in a direction orthogonal to the lower electrode 12a (that is, in a direction parallel to the surface electrode 7), and is a separation portion interposed between the drift portions 6a adjacent to each other in the extension direction of the lower electrode 12a. 6b is divided and protrudes toward the face plate 30 side. Here, the partition wall 13 is formed in a strip shape, and the thickness (thickness in the extending direction of the lower electrode 12a) is set to about several μm according to the interval between the sub-pixels.
The pitch between the partition walls 13 in the extension direction of 2a is 50 μm
It is set to about 100 μm.

As the partition wall 13, the insulating substrate 11 is used.
Types of partition walls 13a, 1 having different protrusion sizes from each other
3b, the partition 13a having a small projection size from the insulating substrate 11 has a projection size of 500 μm or less, and the partition 13b having a large projection size from the insulating substrate 11 has a projection size of the insulating substrate 11 and the face plate 30. Is set so as to maintain a specified distance (for example, 2 mm to 5 mm). That is, since the partition wall 13b also serves as a reinforcing spacer for keeping the insulating substrate 11 and the face plate 30 at a specified distance, a reinforcing spacer separate from the insulating substrate 11 is used as the insulating substrate. The step of positioning and arranging with respect to 11 is unnecessary, and the assembly process of the display is simplified. Such a ceramic substrate can be easily formed by a sintering method or the like, and the partition wall 13 can be easily adapted to various shapes.
The partitions 13a and the partitions 13b do not have to be alternately arranged, and the interval between the partitions 13b also serving as the reinforcing spacer may be set to, for example, about 1 cm to 2 cm.

In the field emission electron source 10 according to this embodiment, however, the electron source element 10a emits the electron between the face plate 30 facing the insulating substrate 11 on one surface side of the insulating substrate 11. Since each of the electron source elements 1 has a partition wall 13 that limits the spread of the electron beam.
The spread of the electron beam emitted from 0a is limited by the partition wall 13, the variation in the emission direction of the electron beam is small, and the spread of the emitted electron beam is small. Therefore, it is possible to reduce the angular distribution of the electron emission direction. It can be applied to required high-definition displays and devices that require equivalent angular distribution. Further, the electron source element 10 according to the present embodiment
In a, since the emission direction of the emitted electron beam is easily aligned with the normal direction of the surface electrode 7 and the angular distribution of the electron emission direction is relatively small, the brightness of the screen of the display can be increased.

Further, in this embodiment, since the cross section of the partition wall 13 which is orthogonal to the thickness direction of the insulating substrate 11 is formed in a straight line shape, the electrons are provided between the electron source elements 10a arranged with the partition wall 13 interposed therebetween. Can be prevented from overlapping, so that electrons can be prevented from reaching the sub-pixels corresponding to the electron source elements 10a adjacent to each other in the direction in which the R, G, and B sub-pixels are arranged side by side, and colors due to color mixing can be prevented. The shift can be prevented.

Further, in this embodiment, the thickness of the insulating substrate 11 is set so that the insulating substrate 11 can be used as a rear plate.
0 and supporting spacers (not shown) also serve as a rear plate for forming an airtight space in which all electron source elements 10a are housed, so that the field emission electron source 10 is bonded to the rear plate made of a glass substrate. The number of parts can be reduced, the number of assembling steps can be reduced, and the cost can be reduced as compared with the case of using the same. In addition, Al ₂ O ₃ ,
Since ceramics such as AiN and SiC have a higher thermal conductivity than glass, the electron source element 10 is different from the conventional case where the insulating substrate 11 ′ made of a glass substrate is used.
The heat generated in a can be efficiently dissipated, and the reliability as an electron source can be improved.

Incidentally, the electron source element 10 in this embodiment.
Since a has a small degree of vacuum dependence of emission current and electron emission efficiency and can stably emit electrons even in a relatively low vacuum, airtightness surrounded by the face plate 30, the insulating substrate 10 and the supporting spacers is used. The vacuum degree of space is 10
^-4 Pa to 10 ¹ Pa is set.

Further, in this embodiment, as described above, since the ceramic substrate in which the partition wall 13 and the lower electrode 12a are integrally formed on the insulating substrate 11 is used, the lower electrode 12a should be formed regardless of the partition wall 13. Therefore, there is an advantage that the layout design of the lower electrode 12a becomes easy, but it is not always necessary to integrally form the lower electrode 12a on the insulating substrate 11, and for example, as shown in FIG. A ceramic substrate in which only 13 is integrally formed may be used. Here, in the present embodiment, the partition wall 1
Since 3 is made of ceramic, it is possible to easily form the partition wall 13 and to increase the mechanical strength of the partition wall 13 as compared with the case of using glass.

Further, each of the electron source elements 10a described above is provided for each sub-pixel made of any one of R, G, and B phosphors provided on the side of the face plate 30 facing the field emission electron source 10. Therefore, if the surface electrode 7 and the lower electrode 12a are formed only in a portion that overlaps the drift portion 6a in the thickness direction of the insulating substrate 11 and the bus electrode made of a low resistance conductive material is provided, The delay time until the electron beam is emitted from the generated electron source element 10a can be shortened, and the reduction or variation of the emission current due to the voltage drop in the wiring can be suppressed.

(Embodiment 2) The field emission type electron source 10 according to the present embodiment has substantially the same basic configuration as that of Embodiment 1, and as shown in FIG. 5, the partition wall 13 has a different shape from that of Embodiment 1. is doing. The partition wall 13 in the field emission electron source 10 of the present embodiment is the same in that it is integrally formed on the insulating substrate 11, but the spread of the electron beam emitted from the electron source element 10a is extended by the lower electrode 12a. The first portion (the portion extending in the left-right direction in FIG. 5) 13d that limits the direction and the spreading direction of the electron beam emitted from the electron source element 10a (the left-right direction in FIG. 5). And a second portion 13c that limits the distance. Here, the surface electrode 7 is wired through a gap 14 formed between the partition walls 13 adjacent to each other in the extension direction of the lower electrode 12. That is, the surface electrode 7 is formed in a comb shape, and the second portion 13d of the partition wall 13 corresponds to the comb groove.
Is located. The same components as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

Therefore, in this embodiment, for example, the extension direction of the lower electrode 12a is the row direction of the matrix, and the surface electrode 7 is
If the extension direction of each partition is the column direction of the matrix, each partition wall 13
Is used as an electron source for a full-color display, since it has a site (the second site 13d) that restricts the spread of the electron beam in the row direction of the matrix and a site (the first site 13c) that restricts the spread of the electron beam in the column direction. If
It is possible to prevent the electrons emitted from each electron source element 10a from reaching the sub-pixel corresponding to the electron source element 10a adjacent in the row direction and the sub-pixel corresponding to the electron source element 10a adjacent in the column direction. Therefore, it is possible to prevent color shift due to color mixture.

Further, each of the electron source elements 10a described above is provided for each sub-pixel made of any one of R, G, and B phosphors provided on the surface of the face plate 30 facing the field emission electron source 10. Therefore, if the surface electrode 7 and the lower electrode 12a are formed only in a portion that overlaps the drift portion 6a in the thickness direction of the insulating substrate 11 and the bus electrode made of a low resistance conductive material is provided, The delay time until the electron beam is emitted from the generated electron source element 10a can be shortened, and the reduction or variation of the emission current due to the voltage drop in the wiring can be suppressed.

Also, as in the first embodiment, a plurality of partition walls 1
For at least one partition wall 13 of the three, the reinforcing spacer for maintaining the protruding dimension from the one surface of the insulating substrate 11 so that the partition wall 13 keeps the insulating substrate 11 and the face plate 30 at a specified distance. If it is set so that it can also serve as the insulating substrate 11, the step of positioning and arranging the reinforcing spacer, which is separate from the insulating substrate 11, with respect to the insulating substrate 11 is unnecessary, and the display assembling process is simplified. Be converted.

By the way, in this embodiment, the insulating substrate 1 is used.
Although a ceramic substrate integrally formed with a plurality of partition walls 13 having the above-described shape is used as No. 1, a cross section orthogonal to the thickness direction of the insulating substrate 11 is formed in a mesh shape as shown in FIG. 6, for example. By using a ceramic substrate integrally formed with the partition wall 13 and disposing one electron source element 10a in each mesh (the mesh is formed in a rectangular shape in the example of FIG. 6), The spread of the electron beam emitted from the electron source element 10a is restricted over the entire circumference for each electron source element 10a, and when used as the electron source of a full-color display, It is possible to prevent emitted electrons from reaching the sub-pixels corresponding to the electron source elements 10a adjacent in the row direction and the sub-pixels corresponding to the electron source elements 10a adjacent in the column direction. From, it is possible to prevent the color shift due to mixing.

By the way, in each of the above embodiments, the drift portion 6a of the strong electric field drift layer 6 is formed by the oxidized porous polycrystalline silicon layer. However, the drift portion 6a is nitrided or oxynitrided. It may be formed of a layer, or may be formed by oxidizing, nitriding, or oxynitriding a porous semiconductor layer other than the porous polycrystalline silicon layer. When the drift portion 6a is formed of a nitrided porous polycrystalline silicon layer, each silicon oxide film 5 described in FIG.
Both 2 and 64 are silicon nitride films, and when the drift portion 6a is an oxynitrided porous polycrystalline silicon layer, both silicon oxide films 52 and 64 are silicon oxynitride films.

In each of the above embodiments, the insulating substrate 1
The partition wall 13 is integrally formed on the first plate 1, but the partition wall 13 may be integrally formed on the face plate 30. In this case,
The step of positioning the partition wall 13 with respect to the face plate 30 is unnecessary, the assembly process can be simplified, and the production cost can be reduced.

[0048]

According to the invention of claim 1, an insulating substrate, a plurality of electron source elements formed on one surface side of the insulating substrate to emit electrons, and an insulating substrate on one surface side of the insulating substrate. And a partition wall that limits the spread of the electron beam emitted from the electron source element between the face plate and the face plate that face each other, and the spread of the electron beam emitted from the electron source element is limited by the partition wall. Since there is little variation in the emission direction of the electron beam and the spread of the emitted electron beam is small, the device is required to have a small angular distribution in the electron emission direction like the electron source of a high-definition display. There is an effect that it can be applied.

According to a second aspect of the present invention, in the first aspect of the invention, the electron source element includes a lower electrode formed on the one surface side of the insulating substrate, and an electron source element on the one surface side in the thickness direction of the insulating substrate. A surface electrode facing the lower electrode, and a drift portion formed of an oxidized, nitrided, or oxynitrided porous semiconductor layer interposed between the lower electrode and the surface electrode, and the surface electrode between the surface electrode and the lower electrode. Electrons injected from the lower electrode drift through the drift electrode and are emitted through the surface electrode due to the electric field that acts on the drift portion when a voltage is applied with the high potential side as the emission source of the electron beam emitted from the electron source element. Since the directions are easily aligned with the normal direction of the surface electrode and the angular distribution of the electron emission direction is relatively small, increase the screen brightness when used as the electron source of the display. There is an effect that can be.

According to a third aspect of the present invention, in the first or second aspect of the invention, a plurality of electron source elements are arranged at positions corresponding to the lattice points of the matrix, and a plurality of partition walls are provided. Since the cross section orthogonal to the thickness direction of the insulating substrate is formed in a straight line, it is possible to prevent the spread of electrons from overlapping between the electron source elements arranged with the partition wall interposed therebetween. When used as a light source, electrons can be prevented from reaching subpixels corresponding to electron source elements adjacent to each other in the juxtaposed direction of R, G, and B subpixels, and color shift due to color mixing can be prevented. The effect is that you can.

According to a fourth aspect of the present invention, in the first or second aspect of the present invention, the partition wall has a mesh-shaped cross section orthogonal to the thickness direction of the insulating substrate, and an electron is formed in the mesh-shaped mesh. Since the source elements are arranged one by one, the spread of the electron beam emitted from each electron source element by disposing one electron source element in the mesh of the mesh-shaped partition wall Is limited over the entire circumference, and when used as an electron source of a full-color display, the electrons emitted from each electron source element have sub-pixels and columns corresponding to electron source elements adjacent in the row direction. Since it can be prevented from reaching the sub-pixels corresponding to the electron source elements adjacent in the direction, there is an effect that color shift due to color mixture can be prevented.

According to a fifth aspect of the present invention, in the first or second aspect of the invention, a plurality of electron source elements are arranged at positions corresponding to the lattice points of the matrix, and a plurality of partition walls are provided. Has a part that restricts the spread of the electron beam in the row direction of the matrix and a part that restricts the spread of the electron beam in the column direction. Therefore, when used as an electron source of a full-color display, the electrons emitted from each electron source element are arranged in the row direction. Since it is possible to prevent the sub-pixels corresponding to the adjacent electron source elements and the sub-pixels corresponding to the adjacent electron source elements in the column direction from being reached, it is possible to prevent color shift due to color mixture. is there.

According to a sixth aspect of the invention, in the third or fifth aspect of the invention, at least one of the plurality of partition walls also serves as a spacer for keeping a prescribed distance between the insulating substrate and the face plate. , The step of positioning and arranging a reinforcing spacer, which is separate from the insulative substrate, with respect to the insulative substrate is unnecessary, and when used as an electron source of a display, the assembly process can be simplified. .

According to a seventh aspect of the invention, in the invention of the fourth aspect, the partition wall is an insulating substrate so that a part of a mesh-like mesh portion keeps a prescribed distance between the insulating substrate and the face plate. Since it is extended in the thickness direction of the base plate, the partition wall has a function as a reinforcing spacer for keeping the distance between the insulating substrate and the face plate at a specified distance. There is no need for a step of positioning and arranging a spacer for use with the insulating substrate, and there is an effect that the assembly step is simplified when used as an electron source of a display.

According to the invention of claim 8, in the invention of claims 1 to 7, since the partition wall is made of ceramic,
Compared with the case where the partition wall is made of glass, the partition wall can be easily produced and the mechanical strength of the partition wall can be increased.

According to a ninth aspect of the invention, in the first to eighth aspects of the invention, since the partition wall and the insulating substrate are integrally formed, the step of disposing the partition wall with respect to the insulating substrate is unnecessary. There is an effect that the production cost can be reduced.

According to a tenth aspect of the present invention, in the first to seventh aspects of the present invention, the partition wall is formed integrally with the face plate. Therefore, when the partition wall is used as an electron source of a display, the partition wall is to the face plate. Since the process of positioning and arranging is not required, the assembly process can be simplified,
This has the effect of reducing production costs.

[Brief description of drawings]

FIG. 1 shows the first embodiment and is a schematic configuration diagram of a display using a field emission electron source.

FIG. 2 is a schematic configuration diagram of the above field emission electron source.

FIG. 3 is a schematic explanatory diagram of a main part of the above.

FIG. 4 is a schematic configuration diagram of a main part of another configuration example of the above.

FIG. 5 is a schematic configuration diagram of a field emission electron source showing a second embodiment.

FIG. 6 is a schematic configuration diagram of a main part of another configuration example of the above.

FIG. 7 is an operation explanatory view of a field emission type electron source showing a conventional example.

FIG. 8 is an explanatory diagram of an operation of the above field emission electron source.

FIG. 9 is an operation explanatory view of a field emission electron source showing another conventional example.

FIG. 10 is a schematic configuration diagram of a display using the same as above.

FIG. 11 is an explanatory view of a main part of a display using the same as above.

[Explanation of symbols]

6 Strong electric field drift layer 6a Drift section 6b Separation part 7 Surface electrode 10 Field emission electron source 10a Electron source element 11 Insulating substrate 13 partitions 12a lower electrode 30 face plate

Continued front page    (72) Inventor Takuya Komoda             1048, Kadoma, Kadoma-shi, Osaka Matsushita Electric Works Co., Ltd.             Inside the company (72) Inventor Tsutomu Kagehara             1048, Kadoma, Kadoma-shi, Osaka Matsushita Electric Works Co., Ltd.             Inside the company (72) Inventor Yoshifumi Watanabe             1048, Kadoma, Kadoma-shi, Osaka Matsushita Electric Works Co., Ltd.             Inside the company (72) Inventor Takashi Hatai             1048, Kadoma, Kadoma-shi, Osaka Matsushita Electric Works Co., Ltd.             Inside the company (72) Inventor Toru Baba             1048, Kadoma, Kadoma-shi, Osaka Matsushita Electric Works Co., Ltd.             Inside the company F-term (reference) 5C032 AA01 CC10                 5C036 EE03 EE14 EF01 EF06 EF09                       EG02 EG12 EH04 EH05 EH11

Claims (10)

[Claims] 1. An insulating substrate, a plurality of electron source elements which are formed on one surface side of the insulating substrate and emit electrons, and a face plate which is arranged on the one surface side of the insulating substrate so as to face the insulating substrate. A field emission electron source, comprising: a partition wall that restricts the spread of an electron beam emitted from the electron source element. 2. The electron source element includes a lower electrode formed on the one surface side of an insulating substrate, a surface electrode facing the lower electrode on the one surface side in the thickness direction of the insulating substrate, and a lower electrode. A drift portion formed of an oxidized, nitrided or oxynitrided porous semiconductor layer interposed between the surface electrode and the surface electrode, and drifts when a voltage is applied between the surface electrode and the lower electrode with the surface electrode on the high potential side. 2. The field emission electron source according to claim 1, wherein electrons injected from the lower electrode drift in the drift portion and are emitted through the surface electrode by an electric field acting on the portion. 3. A plurality of electron source elements are respectively arranged at positions corresponding to lattice points of a matrix, and a plurality of partition walls are provided, and each partition wall has a linear cross section orthogonal to the thickness direction of the insulating substrate. The field emission electron source according to claim 1 or 2, wherein 4. The partition is characterized in that a cross section of the insulating substrate orthogonal to the thickness direction is formed in a mesh shape, and one electron source element is disposed in each mesh of the mesh shape. The field emission electron source according to claim 1 or 2. 5. A plurality of electron source elements are respectively arranged at positions corresponding to lattice points of a matrix, and a plurality of partition walls are provided, and each partition wall restricts the spread of an electron beam in the row direction of the matrix. The field emission electron source according to claim 1 or 2, wherein the field emission electron source has a portion that is restricted in a direction. 6. The field emission type according to claim 3, wherein at least one of the plurality of partition walls also serves as a spacer for keeping a predetermined distance between the insulating substrate and the face plate. Electron source. 7. The partition wall is formed by extending a part of a mesh-shaped mesh portion in a thickness direction of the insulating substrate so as to maintain a predetermined distance between the insulating substrate and the face plate. The field emission electron source according to claim 4. 8. The field emission type electron source according to claim 1, wherein the partition wall is made of ceramics. 9. The field emission electron source according to claim 1, wherein the partition wall and the insulating substrate are integrally formed. 10. The field emission electron source according to claim 1, wherein the partition wall is formed integrally with the face plate.