WO2006070446A1

WO2006070446A1 - Electron emitting element, electron emitting device, display and light source

Info

Publication number: WO2006070446A1
Application number: PCT/JP2004/019588
Authority: WO
Inventors: Yukihisa Takeuchi; Tsutomu Nanataki; Iwao Ohwada
Original assignee: Ngk Insulators, Ltd.
Priority date: 2004-12-28
Filing date: 2004-12-28
Publication date: 2006-07-06
Also published as: CN1871683A

Abstract

An electron emitting element (10A) is provided with a lower electrode (16) formed on a glass substrate (11); an emitter part (12) composed of a dielectric film formed on the lower electrode (16); and an upper electrode (14) formed on the emitter part (12). A driving voltage (Va) for electron emission is applied between the upper electrode (14) and the lower electrode (16). At least the upper electrode (14) is provided with a plurality of penetrating parts (20) from which the emitter part (12) is exposed. In the upper electrode (14), a plane (26a) facing the emitter part (12) at a circumference part (26) of the penetrating part is separated from the emitter part (12).

Description

Specification

Electron emitter, electron emitter, display and light source

Technical field

[0001] The present invention relates to an electron-emitting device formed on a glass substrate, an electron-emitting device having a plurality of the electron-emitting devices, a display using the electron-emitting device, and a light source using the electron-emitting device. About.

Background art

[0002] Recently, an electron-emitting device has a force sword electrode and an anode electrode, and is applied to various abrasions such as a field emission display (FED) and a backlight. When applied to FED, a plurality of electron-emitting devices are two-dimensionally arranged, and a plurality of phosphors for these electron-emitting devices are arranged with a predetermined interval.

[0003] As a conventional example of this electron-emitting device, for example, there is Patent Document 15, but since neither of them uses a dielectric in the emitter part, forming processing or fine processing is required between the counter electrodes. In addition, a high voltage must be applied for electron emission, and the panel manufacturing process is complicated and the manufacturing cost increases.

[0004] Therefore, it is considered that the emitter portion is made of a dielectric, and various theories are described in the following Non-Patent Document 13 regarding electron emission from the dielectric. 1-31 1 533

Patent Document 2: Japanese Patent Application Laid-Open No. 7-1 47 1 31

Patent Document 3: Japanese Patent Laid-Open No. 2000-285801

Patent Document 4: Japanese Patent Publication No. 46-20944

Patent Document 5: Japanese Patent Publication No. 44-261 25

Non-Patent Document 1: Yasuoka, Ishii, "Pulsed electron source using a ferroelectric cathode" Applied Physics Vol. 68, No. 5, p 546 550 (1 999) Non-Patent Document 2: VF Puchkarev, GA Mesyats, On the mechanism of emission from the ferroelectric ceramic cathode, J. Appl. Phys., Vol. 78, No. 9, 1 November, 1995, p. 5633-5637

Non-Patent Document 3: H. Riege, Electron emission ferroelectrics-a review, Nuc, Inst and Meth. A340, p. 80-89 (1994)

Disclosure of the invention

Problems to be solved by the invention

Incidentally, in the conventional electron-emitting device 200, as shown in FIG. 40, when the upper electrode 204 and the lower electrode 206 are formed on the emitter section 202, the upper electrode 204 is in close contact with the emitter section 202 in particular. Will be formed. The electric field concentration point is the triple point of the upper electrode 204Z emitter 202Z vacuum. In this case, the peripheral portion of the upper electrode 204 corresponds.

[0006] However, since the peripheral portion of the upper electrode 204 is in close contact with the emitter portion 202, there is a problem that the degree of electric field concentration is small and the energy required to emit electrons is small. In addition, since the electron emission location is limited to the peripheral portion of the upper electrode 204, there are variations in the overall electron emission characteristics, which makes it difficult to control the electron emission and has a problem of low electron emission efficiency.

[0007] The present invention has been made in consideration of such a problem, and can easily generate a high electric field concentration, and can increase the number of electron emission locations. An object of the present invention is to provide an electron-emitting device and an electron-emitting device that can achieve high efficiency, can be driven at a low voltage, and are advantageous in increasing the size and reducing the product cost.

[0008] Further, another object of the present invention is to achieve high output and high efficiency with respect to electron emission, and can be driven at a low voltage, and is advantageous in increasing the plate size and reducing the product cost. An object of the present invention is to provide a high-luminance and low-cost display and light source using a simple electron emission device.

Means for solving the problem

[0009] An electron-emitting device according to the present invention includes a first electrode formed on a glass substrate, An emitter section made of a dielectric film formed on the first electrode; and a second electrode formed on the emitter section. The driving voltage for electron emission is Applied between the second electrode and the second electrode, wherein at least the second electrode has a plurality of through portions from which the emitter portion is exposed, and of the second electrode, the peripheral portion of the through portion The surface facing the emitter part in is separated from the emitter part.

[0010] Further, an electron emission device according to the present invention is an electron emission device having a plurality of electron emission elements formed on a glass substrate, wherein the electron emission elements are formed on the glass substrate. A first electrode, an emitter portion made of a dielectric film formed on the first electrode, and a second electrode formed on the emitter portion, and a drive voltage for electron emission Is applied between the first electrode and the second electrode, and at least the second electrode has a plurality of penetrating portions from which the emitter portion is exposed, and among the second electrodes, A surface of the peripheral portion of the penetrating portion facing the emitter portion is separated from the emitter portion.

[0011] In addition, a display according to the present invention includes: the above-described electron emission device; a transparent plate disposed on a surface of the glass substrate facing an emitter portion of the electron emission device; Among them, an electrode for forming an electric field with the electron-emitting device in the electron-emitting device and a phosphor formed on the electrode on a surface facing the emitter section, The emitted electrons collide with the phosphor to excite the phosphor to emit light.

[0012] Further, the light source according to the present invention includes the above-described electron emission device, a transparent plate disposed opposite to a surface of the glass substrate on which the emitter portion is formed, and the transparent substrate. An electrode for forming an electric field with the electron-emitting device in the electron-emitting device and a phosphor formed on the electrode on a surface of the plate facing the emitter section, and the electron-emitting device Electrons emitted from an element collide with the phosphor to excite the phosphor to emit light. [0013] First, a drive voltage is applied between the first electrode and the second electrode. This drive voltage rapidly increases from a voltage level higher or lower than a reference voltage (for example, OV) to a voltage level lower or higher than the reference voltage with time, such as a pulse voltage or an AC voltage. Is defined as the voltage that changes to.

[0014] In addition, a triple junction is formed at a contact point between the surface of the emitter section where the second electrode is formed, the second electrode, and a medium (for example, vacuum) around the electron-emitting device. . Here, the triple junction is defined as an electric field concentration portion formed by contact between the second electrode, the emitter portion, and the vacuum. The triple junction includes a triple point where the second electrode, the emitter part, and the vacuum exist as one point. In the present invention, the ripple junction is formed in the peripheral portion of the plurality of through portions and the peripheral portion of the second electrode. Therefore, when the drive voltage as described above is applied between the first electrode and the second electrode, electric field concentration occurs in the triple junction described above.

[0015] In the first stage, a voltage higher or lower than the reference voltage is applied between the first electrode and the second electrode, and electric field concentration in one direction occurs in the triple junction described above, for example. Then, electrons are emitted from the second electrode toward the emitter. For example, electrons are emitted from the emitter to the portion corresponding to the penetrating portion of the second electrode or the vicinity of the peripheral portion of the second electrode. Accumulated. That is, the emitter section is charged. At this time, the second electrode functions as an electron supply source.

[0016] In the next second stage, when the voltage level of the driving voltage changes suddenly and a voltage lower or higher than the reference voltage is applied between the first electrode and the second electrode, The electron charged in the part corresponding to the penetrating part of the second electrode or in the vicinity of the peripheral part of the second electrode is the dipole of the emitter part whose polarity is reversed in the reverse direction (negative polarity appears on the surface of the emitter part) As a result, the electrons are expelled from the emitter portion, and electrons are emitted from the portion of the emitter portion where the electrons are accumulated through the penetrating portion. Of course, electrons are also emitted from the vicinity of the outer periphery of the second electrode. At this time, before Electrons corresponding to the charge amount of the emitter in the first stage are emitted from the emitter in the second stage. Further, the charge amount of the emitter section in the first stage is maintained until the electron emission in the second stage is performed.

In another electron emission method, first, in the first output period, preparation for electron emission (for example, polarization in one direction of a substance serving as an emitter) is performed. In the next second output period, when the voltage level of the drive voltage changes suddenly, electric field concentration occurs at the triple junction described above, and primary electrons are emitted from the second electrode by this electric field concentration, Of the substance that becomes the emitter, it will collide with the part exposed from the penetrating part and the vicinity of the outer periphery of the second electrode. As a result, secondary electrons (including reflected electrons of primary electrons) are emitted from the part where the primary electrons collide. That is, in the initial stage of the second output period, secondary electrons are emitted from the vicinity of the penetrating portion and the outer peripheral portion of the second electrode.

[0018] In this electron-emitting device, first, since the plurality of through portions are formed in the second electrode, electrons are evenly emitted from the vicinity of each through portion and the outer peripheral portion of the second electrode, Variations in the overall electron emission characteristics are reduced, making it easier to control electron emission and increasing electron emission efficiency.

[0019] In addition, the present invention is a shape in which a gap is formed between the surface of the second electrode facing the emitter portion in the peripheral portion of the penetrating portion and the emitter portion. When a driving voltage is applied, electric field concentration is likely to occur in the gap portion. This leads to higher efficiency of electron emission, and lower drive voltage (electron emission at a lower voltage level) can be realized.

[0020] As described above, in the present invention, a gap is formed between the surface of the second electrode facing the emitter portion in the peripheral portion of the penetrating portion and the emitter portion. Since the peripheral portion of the penetrating portion in the second electrode has a hook shape (flange shape), the electric field concentration in the gap portion increases, and the hook portion (the periphery of the penetrating portion). Part) easily emits electrons. This leads to higher output and higher efficiency of electron emission, and lower drive voltage. it can. As a result, for example, a display or a light source having a large number of electron-emitting devices arranged side by side can be increased in brightness. In addition, either the method of emitting electrons accumulated in a substance serving as an emitter or the method of emitting secondary electrons by colliding primary electrons from the second electrode with a substance serving as an emitter. Since the periphery of the penetrating portion of the second electrode functions as a gate electrode (control electrode, focus electron lens, etc.), the straightness of the emitted electrons can be improved. This is advantageous in reducing crosstalk when configured as a display electron source.

As described above, in the present invention, high electric field concentration can be easily generated, moreover, the number of electron emission locations can be increased, and high output and high efficiency can be achieved for electron emission. Low voltage driving (low power consumption) is also possible. In particular, since glass substrates are used, product costs can be reduced. In addition, it is possible to promote a reduction in the processing temperature for manufacturing the electron-emitting device, and to reduce the cost of the equipment. Crystallized glass may be used as the glass substrate. In this case, the processing temperature can be in the range of 60 0 80 0 ° C, unlike general glass, and the degree of freedom in material selection can be expanded. By using a glass substrate, it is possible to obtain a large plate corresponding to the backlight of a large screen display or large screen liquid crystal display at a low price. In addition, it is possible to make the transparent plate forming the tube wall and spacer, or phosphor, made of glass, and to adhere the glass substrate on which the electron-emitting device is formed, to the glass substrate. If the element is formed on a substrate other than glass, the coefficient of thermal expansion does not match that of other glass members and frits, making it difficult to manufacture the tube.

[0022] In the present invention, in the emitter portion, at least a surface on which the second electrode is formed has irregularities due to dielectric grain boundaries, and the first electrode includes the dielectric The through portion may be formed in a portion corresponding to the concave portion in the grain boundary. The first electrode includes a substance having a scaly shape. Alternatively, a conductive substance or a collection of substances having a plurality of scale-like shapes may be used.

[0023] With this, in the first electrode, the surface of the peripheral portion of the penetrating portion facing the emitter portion is separated from the emitter portion, that is, the peripheral portion of the penetrating portion A configuration in which a gap is formed between the surface facing the emitter portion and the emitter portion can be easily realized.

[0024] As described above, according to the electron-emitting device and the electron-emitting device according to the present invention, high electric field concentration can be easily generated, and more electron emission points can be provided. High output and high efficiency can be achieved, low voltage drive (low power consumption) is possible, and it is advantageous for increasing the plate size and reducing the product cost.

[0025] Further, according to the display and the light source according to the present invention, a large screen or a large area, high luminance, and low cost can be achieved.

Brief Description of Drawings

FIG. 1 is a cross-sectional view showing a partially omitted electron-emitting device according to the first embodiment.

FIG. 2 is an enlarged cross-sectional view showing a partially omitted electron-emitting device according to the first embodiment.

FIG. 3 is a cross-sectional view showing an enlarged main part of the electron-emitting device according to the first embodiment.

FIG. 4 is a plan view showing an example of the shape of a through-hole formed in the upper electrode.

FIG. 5A is a cross-sectional view showing another example of the upper electrode, and FIG. 5B is a cross-sectional view showing an enlarged main part.

FIG. 6A is a cross-sectional view showing still another example of the upper electrode, and FIG. 6B is a cross-sectional view showing an enlarged main part.

FIG. 7 is a diagram showing a voltage waveform of a drive voltage in the first electron emission method.

[FIG. 8] FIG. 8 shows electron emission in the second output period (second stage) of the first electron emission method. It is explanatory drawing which shows a mode of going out.

FIG. 9 is a diagram showing a voltage waveform of a drive voltage in the second electron emission method.

FIG. 10 is an explanatory view showing the state of electron emission in the second output period (second stage) of the second electron emission method.

[FIG. 11] FIG. 11 is a diagram showing an example of a cross-sectional shape of a collar portion of the upper electrode.

FIG. 12 is a diagram showing another example of the cross-sectional shape of the collar portion of the upper electrode.

FIG. 13 is a diagram showing still another example of the cross-sectional shape of the collar portion of the upper electrode.

FIG. 14 is an equivalent circuit diagram showing a connection state of various capacitors connected between the upper electrode and the lower electrode.

[FIG. 15] FIG. 15 is a diagram for explaining the capacitance calculation of various capacitors connected between the upper electrode and the lower electrode.

FIG. 16 is a plan view showing a part of the first modification of the electron-emitting device according to the first embodiment with a part thereof omitted.

FIG. 17 is a plan view showing a second variation of the electron-emitting device according to the first embodiment with a part thereof omitted.

FIG. 18 is a plan view showing the third modification of the electron-emitting device according to the first embodiment with a part thereof omitted.

FIG. 19 is a diagram showing voltage-charge amount characteristics (voltage-polarization amount characteristics) of the electron-emitting device according to the first embodiment.

20 is an explanatory diagram showing the state at point p 1 in FIG. 19, and FIG. 20 is an explanatory diagram showing the state at point p 2 in FIG. C is an explanatory diagram showing a state from point p 2 to point p 3 in FIG.

[Fig. 21] Fig. 21A is an explanatory diagram showing the state from point p3 to point p4 in Fig. 19. Fig. 21B shows the state immediately before reaching point p4 in Fig. 19. FIG. 21C is an explanatory diagram illustrating a state from point p4 to point p6 in FIG.

[FIG. 22] FIG. 22 is configured using the electron-emitting device according to the first embodiment. It is a block diagram which shows light emission display parts, such as a display, and a drive circuit.

[FIG. 23] FIGS. 2 3 A 2 3 C are waveform diagrams showing the amplitude modulation of the pulse signal by the amplitude modulation circuit.

FIG. 24 is a block diagram showing a signal supply circuit according to a modification.

FIG. 25 is a waveform diagram showing pulse width modulation of the pulse signal by the pulse width modulation circuit.

[Fig.26] Fig. 26 A shows a hysteresis curve when voltage V s I is applied in Fig. 23 A or Fig. 25 A, and Fig. 26 B shows Fig. 23 B or Fig. 25 Fig. 26 is a diagram showing a hysteresis curve when voltage V sm is applied at B. Fig. 26 C is a diagram showing a hysteresis curve when voltage V sh in Fig. 23C or Fig. 25C is applied. It is.

[FIG. 27] FIG. 27 is a configuration diagram showing one arrangement example of the collector electrode, the phosphor, and the transparent plate on the upper electrode.

FIG. 28 is a block diagram showing another arrangement example of the collector electrode, the phosphor and the transparent plate on the upper electrode.

[Fig.29] Fig. 29 A is a diagram showing the waveforms of the write pulse and the lighting pulse used in the first experimental example (experiment of the electron emission state of the electron-emitting device). FIG. 6 is a diagram showing the state of electron emission from the electron-emitting device in the experimental example in FIG.

FIG. 30 is a diagram showing waveforms of an address pulse and a lighting pulse used in the second and fourth experimental examples.

[FIG. 31] FIG. 31 is a characteristic diagram showing the results of a second experimental example (an experiment in which the amount of electrons emitted from the electron-emitting device varies depending on the amplitude of the write pulse).

[FIG. 32] FIG. 32 is a characteristic diagram showing the results of a third experimental example (an experiment in which the amount of electrons emitted from the electron-emitting device varies depending on the amplitude of the lighting pulse).

[Figure 33] Figure 33 shows the fourth experimental example (the amount of electrons emitted from the electron-emitting device is the collector FIG. 6 is a characteristic diagram showing the results of an experiment) that shows how the pressure changes depending on the pressure level.

FIG. 34 is a timing chart showing an example of a driving method for a display or the like.

FIG. 35 is a table showing the relationship between applied voltages in the driving method shown in FIG. 34.

FIG. 36 is a cross-sectional view showing the electron-emitting device according to the second embodiment with a part thereof omitted.

FIG. 37 is a cross-sectional view showing a part of the first modification of the electron-emitting device according to the second embodiment with a part thereof omitted.

FIG. 38 is a cross-sectional view showing a part of the second modification of the electron-emitting device according to the second embodiment with a part thereof omitted.

FIG. 39 is a cross-sectional view showing a third modification of the electron-emitting device according to the second embodiment with a part thereof omitted.

FIG. 40 is a cross-sectional view showing a partially omitted electron-emitting device according to a conventional example.

Explanation of symbols

1 O A. 1 0 A a, 1 0 A c, 1 0 B. 1 0 B a 1 0 B c: Electron-emitting device 1 2: Emitter part 1 4 ... Upper electrode

1 6… Lower electrode 2 0… Penetration part

2 2… Uneven 2 4… Recess

2 6 ... Buttocks 2 8 ... Gap

3 0 ... Projection 3 2 ... Hole

4 4, 4 6 ... Notches 4 8 ... Slippers

5 0… Floating electrode 1 0 0… Display etc.

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiments of the electron-emitting device according to the present invention will be described below with reference to FIGS. [0029] First, the electron emission device according to the present embodiment can be applied not only as a display but also to an electron beam irradiation device, a light source, an alternative use of an LED, an electronic component manufacturing device, and an electronic circuit component.

[0030] The electron beam in the electron beam irradiation apparatus has high energy and excellent absorption performance as compared with the ultraviolet light in the currently widely used ultraviolet irradiation apparatus. Examples of applications include the use of semiconductor devices to solidify insulation films when stacking wafers, the use of printing inks to cure evenly when printing is dried, and the use of sterilizing medical equipment in packages. is there.

[0031] Applications as a light source include a planar light source such as a backlight for a liquid crystal display and a light source application for a projector that uses a high-intensity, high-efficiency specification such as an ultra-high pressure mercury lamp. When the electron-emitting device according to this embodiment is applied to a light source, it has features such as downsizing, long life, high-speed lighting, and reduction of environmental load due to mercury-free.

[0032] Alternative uses of LED include surface light source applications such as indoor lighting, automotive lamps, and traffic lights, and backlights for small liquid crystal displays for chip light sources, traffic lights, and mobile phones.

[0033] Applications of the electronic component manufacturing apparatus include an electron beam source for a film forming apparatus such as an electron beam evaporation apparatus, a plasma generation (for activation of gas, etc.) in a plasma CVD apparatus, an electron source, and an electron for gas decomposition application. There are sources. There are also vacuum microdevice applications such as tera-Hz-driven high-speed switching elements and high-current output elements. In addition, it is also preferably used as a printer component, that is, a light-emitting device that exposes a photosensitive drum in combination with a phosphor, and an electron source for charging a dielectric.

[0034] As an electronic circuit component, a large current output and a high amplification factor are possible.

Applications include digital devices such as switches, relays, and diodes, and analog devices such as operational amplifiers.

First, as shown in FIG. 1, an electron-emitting device 1 OA according to the first embodiment is formed on a glass substrate 11 and is a plate-like emitter made of a dielectric. Part 1 2, first electrode (eg lower electrode) 16 formed on the first surface (eg lower surface) of the emitter part 1 2, and second surface (eg upper surface) of the emitter part 1 2 A formed second electrode (for example, an upper electrode) 14, and a pulse generation source 18 for applying a driving voltage Va between the upper electrode 14 and the lower electrode 16 are provided.

As shown in FIG. 2, the upper electrode 14 has a plurality of through portions 20 through which the emitter portion 12 is exposed. In particular, the surface of the emitter portion 12 is formed with irregularities 22 due to dielectric grain boundaries, and the through portions 20 of the upper electrode 14 are portions corresponding to the concave portions 24 in the dielectric grain boundaries. Is formed. The example of FIG. 2 shows the case where one through portion 20 is formed corresponding to one concave portion 24, but one through portion 20 is formed corresponding to a plurality of concave portions 24. Sometimes it is done. The particle size of the dielectric constituting the emitter section 12 is preferably 0.1 m 10 m, and more preferably 2 m 7 m. In the example of Fig. 2, the particle size of the dielectric is 3 m.

Furthermore, in the first embodiment, as shown in FIG. 3, a surface 26 6 a facing the emitter portion 12 in the peripheral portion 26 of the penetrating portion 20 is included in the upper electrode 14. , Away from the emitter 1 2. That is, in the upper electrode 14, a gap 28 is formed between the surface 26 6 a facing the emitter portion 12 in the peripheral portion 26 of the penetrating portion 20 and the emitter portion 12, and the upper electrode 14 The peripheral portion 26 of the penetrating portion 20 is formed in a bowl shape (flange shape). Therefore, in the following description, “the peripheral portion 2 6 of the through portion 20 of the upper electrode 14” is referred to as “the upper portion 2 6 of the upper electrode 14”. In addition, in the examples of Fig. 1, Fig. 2, Fig. 3, Fig. 5 A, Fig. 5 B, Fig. 6 A, Fig. 6 B, Fig. 8, Fig. 10, 0, Fig. 1 1 Fig. 13 and Fig. 18, the dielectric The cross section of the convex portion 30 of the grain boundary irregularities 22 is typically shown in a semicircular shape, but is not limited to this shape.

[0038] In the first embodiment, the thickness t of the upper electrode 14 is set to 0.01 m ≤ t ≤ 10 m, and the upper surface of the emitter section 12, that is, the grain boundary of the dielectric The maximum angle 0 between the surface of the convex part 3 0 (which is also the inner wall surface of the concave part 2 4) and the bottom face 2 6 of the upper electrode 1 4 2 6 a is 1 ° ≤0≤6 0 ° The In addition, the maximum along the vertical direction between the surface of the convex portion 30 (inner wall surface of the concave portion 24) at the dielectric grain boundary of the emitter portion 12 and the lower surface 26a of the flange portion 26 of the upper electrode 14 The distance d is set to 0 m <d≤ 1 0 m.

[0039] Furthermore, in the first embodiment, the shape of the penetrating portion 20, in particular, as shown in FIG. 4, is the shape of the hole 32, for example, a circular shape or an elliptical shape. Some include curved parts such as tracks, and some polygons such as squares and triangles. In the example of FIG. 4, the hole 32 has a circular shape.

[0040] In this case, the average diameter of the holes 32 is set to 0.1 m or more and 10 m or less. This average diameter indicates the average length of a plurality of different line segments passing through the center of the hole 32.

[0041] Here, materials and the like of each component will be described. As the dielectric composing the emitter section 12, a dielectric having a relatively high relative dielectric constant, for example, 1 000 or more can be used. Such dielectrics include barium titanate, lead zirconate, lead magnesium niobate, lead nickel niobate, lead zinc niobate, lead manganese niobate, lead magnesium tantalate, lead nickel tantalate, antimony Ceramics containing lead stannate, lead titanate, lead magnesium tandastate, lead cobalt niobate, etc., or any combination thereof, those containing 50% by weight or more of these compounds as the main component, Furthermore, lanthanum, calcium, strontium, molybdenum, tungsten, barium, niobium, zinc, nickel, mangan and other oxides, or any combination thereof, or other compounds are appropriately applied to the ceramics. The added one can be mentioned.

[0042] For example, in a two-component system of PMN-PMT (PMN) with lead magnesium niobate (PMN) and lead titanate (PT) (where n and m are mole ratios), the PMN mole ratio is increased. The Curie point is lowered, and the relative dielectric constant at room temperature can be increased.

[0043] Especially, when n = 0. 85-1. 0 and m = 1.0_n, the relative dielectric constant is 3000 or more. It is preferable. For example, when n = 0.91 and m = 0.09, a room temperature relative dielectric constant of 15000 is obtained, and when n = 0.95 and m = 0.05, a room temperature relative dielectric constant of 20000 is obtained.

[0044] Next, in the ternary system of lead magnesium niobate (PMN), lead titanate (PT), and lead zirconate (PZ), in addition to increasing the molar ratio of PMN, A composition near the morphotropic phase boundary (MPB) of cubic or tetragonal and rhombohedral is preferable for increasing the relative dielectric constant. For example, the relative dielectric constant is 5500 at PMN: PT: PZ = 0.375: 0.375: 0.25, the relative dielectric constant at PMN: PT: PZ = 0.5: 0.35: 0.125 4500, which is particularly preferable. Further, it is preferable to improve the dielectric constant by mixing a metal such as platinum in these dielectrics within a range where the insulating property can be ensured. In this case, for example, 20% by weight of platinum may be mixed in the dielectric.

In addition, as described above, a piezoelectric Z electrostrictive layer, an antiferroelectric layer, or the like can be used as the emitter section 12, but when a piezoelectric Z electrostrictive layer is used as the emitter section 12, Piezoelectric Z electrostrictive layers include, for example, lead zirconate, lead magnesium niobate, lead nickel niobate, lead zinc niobate, lead manganese niobate, lead magnesium tantalate, lead nickel tantalate, lead antimony stannate, titanium Examples thereof include ceramics containing lead oxide, barium titanate, lead magnesium tungstate, lead cobalt niobate, or any combination thereof.

[0046] Needless to say, the main component may contain 50% by weight or more of these compounds. Among the ceramics, a ceramic containing lead zirconate is most frequently used as a constituent material of the piezoelectric Z electrostrictive layer constituting the emitter portion 12.

[0047] Further, when the piezoelectric Z electrostrictive layer is formed of ceramics, the ceramics may further include oxides such as lanthanum, calcium, strontium, molybdenum, tanda stainless, barium, niobium, zinc, nickel, manganese, and the like. It May be any combination of these, or a ceramic to which other compounds are appropriately added. In addition, S i OC e O b

2, 2, P

Five

Use ceramics with G e O or any combination of these

3 11

May be. Specifically, P T-P Z-PMN type piezoelectric material with S i O 0.2w

2

t%, or C e O is 0.1 w t%, or P b G e O is 1 2 w t

2 5 3 11

% Added material is preferred.

[0048] For example, it is preferable to use a ceramic containing, as a main component, a component consisting of lead magnesium niobate, lead zirconate and lead titanate, and further containing lanthanum niobium tantalum.

[0049] The piezoelectric Z electrostrictive layer may be dense or porous, and in the case of being porous, the porosity is preferably 40% or less.

[0050] When an anti-ferroelectric layer is used as the emitter section 12, the anti-ferroelectric layer is mainly composed of lead zirconate and a component composed of lead zirconate and lead stannate. In addition, it is desirable to add lead lanthanum oxide to lead zirconate, and to lead zirconate and lead niobate added to components composed of lead zirconate and lead stannate.

[0051] The antiferroelectric layer may be porous. In the case of being porous, the porosity is preferably 30% or less.

[0052] Further, when strontium bismuthate tantalate (SrBiTaO) is used for the emitter portion 12, polarization inversion fatigue is small and preferable. Such polarization

2 2 9

The material with low reversal fatigue is a layered ferroelectric compound, (B i O) ²⁺ (ABO

B a ² P b ² B i ³⁺ , L a ^3+, etc., and the metal B ions are T i ⁴⁺ , T a ⁵⁺ , N b ^5+, etc. It is also possible to add semiconductors to semiconductors by adding additives to barium titanate, lead zirconate, and PZT piezoelectric ceramics. In this case, the electric field concentration can be performed in the vicinity of the interface with the upper electrode 14 that contributes to electron emission by providing a non-uniform electric field distribution in the emitter section 12.

[0053] Further, for example, lead borosilicate glass on piezoelectric Z electrostrictive Z antiferroelectric ceramics. By mixing a glass component such as soot and other low melting point compounds (for example, bismuth oxide), the firing temperature can be lowered.

[0054] When the piezoelectric Z electrostrictive Z antiferroelectric ceramics is used, the shape thereof is a sheet-like molded body, a sheet-like laminated body, or a laminate or adhesive of these on another supporting substrate. It may be.

[0055] Further, by using a lead-free material for the emitter portion 12 or the like, and making the emitter portion 12 a material having a high melting point or transpiration temperature, the electron or ion collision is less likely to be damaged.

[0056] And, as a method for forming the emitter portion 12 on the glass substrate 11 1, various thick film forming methods such as a screen printing method, a dating method, a coating method, an electrophoresis method, an aerosol deposition method, Various thin film forming methods such as ion beam method, sputtering method, vacuum vapor deposition method, ion plating method, chemical vapor deposition method (CVD) and plating can be used.

Among these, the thick film forming method by screen printing method, dating method, coating method, electrophoresis method or the like is a piezoelectric ceramic having an average particle size of 0.015 m, preferably 0.053 m. It can be formed using a paste soot, slurry, suspension, emulsification, sol or the like mainly composed of the above-mentioned particles, and good piezoelectric operation characteristics can be obtained.

[0058] In particular, the electrophoretic method is capable of forming a film with high density and high shape accuracy, and includes "electrochemistry and industrial physical chemistry V o 5 3, N o. 1 (1 9 8 5), p 6 3-6 8 by Kazuo Ansai ”or“ The 1st Electrophoresis Method for High-Order Forming of Ceramics Proceedings (1 9 9 8), p 5-6, p 2 3 2 4 ”and the like as described in technical literature. In this way, it is advisable to select and use a method as appropriate in consideration of the required accuracy and reliability.

[0059] Further, it is preferable to use a method in which a powdered piezoelectric Z electrostrictive material is formed as an emitter portion 12 and impregnated with glass sol particles having a low melting point. By this method, film formation at a low temperature of 700 ° C or below 600 ° C can be achieved. Therefore, it is suitable when the emitter section 12 is formed on the glass substrate 11 as in the first embodiment. The aerosol deposition method is also a method capable of forming a film at a low temperature.

[0060] The upper electrode 14 is made of an organometallic paste that can provide a thin film after firing. For example, a material such as platinum resinate paste is preferably used. Also

, Oxide electrodes that suppress polarization reversal fatigue, for example, ruthenium oxide (RuO)

2

, Iridium oxide (IrO), strontium ruthenate (SrRuO)

twenty three

, La S r CoO (e.g. x = 0.3 or 0.5), La Ca MnO (e.g.

1-x x 3 1-x x 3 e.g. x = 0.2), La Ca Mn Co O (e.g. x = 0.2, y = 0.

1-x x 1-y y 3

05) Or, these are preferably mixed with platinum resinate paste, for example.

Further, as the upper electrode 14, as shown in FIGS. 5A and 5B, an aggregate 17 of substances 15 (for example, graphite) having a plurality of scale-like shapes, FIG. 6A and FIG. As shown in 6 B, an aggregate 21 of conductive substances 19 including a substance 15 having a scale-like shape is also preferably used. In this case, the aggregate 17 or the aggregate 21 does not completely cover the surface of the emitter portion 1 2, but a plurality of through portions 20 where the emitter portion 1 2 is exposed are provided. Of these, the part facing the penetrating part 20 is defined as an electron emission region.

[0062] The upper electrode 14 is made of the above materials using various thick film forming methods such as screen printing, spraying, coating, dubbing, coating, electrophoresis, sputtering, ion beam method, vacuum deposition. , Ion plating, chemical vapor deposition (CVD), plating, and other conventional thin film formation methods, preferably the former thick film formation method. Good.

On the other hand, the lower electrode 16 is made of a conductive material, for example, metal, and is made of white gold, molybdenum, tungsten, or the like. It is also possible to use conductors that are resistant to high-temperature oxidizing atmospheres, such as simple metals, alloys, mixtures of insulating ceramics and simple metals, and mixtures of insulating ceramics and alloys. Preferably, a high melting point precious metal such as platinum, iridium, palladium, rhodium, and molybdenum, or an alloy such as silver-palladium, silver-platinum, or platinum-palladium, or platinum and a ceramic material. It is composed of cermet materials. More preferably, it is made of a material mainly composed of platinum or a platinum-based alloy.

In addition, as the lower electrode 16, carbon or a graph eyelid material may be used. The ratio of the ceramic material added to the electrode material is preferably about 5 30 volume%. Of course, the same material as that of the upper electrode described above may be used.

The lower electrode 16 is preferably formed by the thick film forming method. The thickness of the lower electrode 16 is preferably 20 m or less, and preferably 5 m or less.

[0066] As a firing treatment of the electron-emitting device 10A, a material that becomes the lower electrode 16, a material that becomes the emitter portion 12, and a material that becomes the upper electrode 14 are sequentially laminated on the glass substrate 11. It may be fired as an integral structure from each other, or heat treatment (firing process) is performed each time the lower electrode 16, the emitter part 12, and the upper electrode 14 are formed to form an integral structure with the glass substrate 11. You may do it. Depending on the formation method of the upper electrode 14 and the lower electrode 16, heat treatment (firing treatment) for integration may not be required.

[0067] As the temperature related to the baking treatment for integrating the emitter portion 1 2 formed on the glass substrate 1 1, the upper electrode 1 4 and the lower electrode 1 6, the glass softening point of the glass substrate 1 1 is In view of this, the range is 5 0 0 1 0 0 0 ° C, preferably 6 0 0 8 0 0 ° C. Further, when the film-like emitter part 12 is heat-treated, it is preferable to perform the baking treatment while controlling the atmosphere together with the evaporation source of the emitter part 12 so that the composition of the emitter part 12 does not become unstable at high temperatures. Good.

[0068] As a method of forming a film on the glass substrate 11, a process and a material that have a temperature lower than the softening point of the glass substrate 11 1 are selected, and the lower electrode 16 on the glass substrate 11 1, The emitter portion 1 2 and the upper electrode 14 are sequentially formed. Specifically, as the lower electrode 16, a silver-paste pad or the like that can be fired at low temperature is formed by screen printing, and after firing, the emitter section 12 is formed by the above-described aero deposition method or a glass having a low melting point. The sol particles are formed by impregnating a powder of piezoelectric Z electrostrictive material, etc., and the upper electrode 14 is formed by screen printing or the like with a material that enables low temperature firing, and then fired. It is a method of doing.

[0069] As another method, a sheet in which the emitter portion 12 is formed at a temperature equal to or higher than the softening point of the glass substrate 11 can be bonded to the glass substrate 11. This method has an advantage that the characteristics necessary for electron emission can be easily obtained because the firing temperature of the emitter section 12 is not limited.

[0070] By performing the firing treatment, in particular, the film to be the upper electrode 14 shrinks from, for example, a thickness of 10 μm to a thickness of 0.1 m, and at the same time, a plurality of holes and the like are formed, and as a result, As shown in FIG. 2, a plurality of through portions 20 are formed in the upper electrode 14, and a peripheral portion 26 of the through portion 20 is formed in a bowl shape. Of course, the film to be the upper electrode 14 may be subjected to patterning by etching (wet etching, dry etching), lift-off, or the like in advance (before firing) and then firing. In this case, as will be described later, a notch shape or a slit shape can be easily formed as the through portion 20.

[0071] It should be noted that a method may be employed in which the emitter portion 12 is covered with an appropriate member and fired so that the surface of the emitter portion 12 is not directly exposed to the firing atmosphere.

Next, the principle of electron emission of the electron-emitting device 1 O A will be described. First, the drive voltage Va is applied between the upper electrode 14 and the lower electrode 16. This drive voltage Va is a voltage level that is higher or lower than a reference voltage (for example, OV) over time, such as a pulse voltage or an AC voltage. Is defined as a voltage that changes rapidly.

[0073] In addition, a triple junction is formed at the contact point between the upper surface of the emitter portion 12 and the upper electrode 14 and the medium (for example, vacuum) around the electron emitter 1OA. Is formed. Here, the triple junction is defined as an electric field concentration portion formed by contact between the upper electrode 14, the emitter portion 1 2, and the vacuum.

. The triple junction also includes a triple point where the upper electrode 14, the emitter portion 1 2, and the vacuum exist as one Boyne rod. The degree of vacuum in the atmosphere is preferably 1 0 ² 1 0 — ^{6 Pa} , more preferably 1 0 — ³ 1 0 — ^{5 Pa} .

[0074] In the first embodiment, the triple junction is a ridge of the upper electrode 14

It is formed at the peripheral edge of 2 6 and the upper electrode 14. Therefore, when the drive voltage Va as described above is applied between the upper electrode 14 and the lower electrode 16, electric field concentration occurs at the above-described ripple junction.

First, the first electron emission method will be described with reference to FIG. 7 and FIG. In the first output period T 1 (first stage) in FIG. 7, a voltage V 2 lower than the reference voltage (in this case, OV) is applied to the upper electrode 14, and the lower electrode 16 is lower than the reference voltage. High voltage V 1 is applied. In the first output period T 1, electric field concentration occurs in the triple junction described above, and electrons are emitted from the upper electrode 14 toward the emitter portion 1 2. For example, the upper portion of the emitter portion 1 2 Electrons are accumulated in a portion exposed from the through portion 20 of the electrode 14 and a portion in the vicinity of the peripheral portion of the upper electrode 14. That is, the emitter section 12 is charged. At this time, the upper electrode 14 functions as an electron supply source.

[0076] In the next second output period T 2 (second stage), the voltage level of the drive voltage V a changes rapidly, that is, the voltage V 1 higher than the reference voltage is applied to the upper electrode 14. When a voltage V 2 lower than the reference voltage is applied to the lower electrode 16, this time, the portion corresponding to the through portion 20 of the upper electrode 14 and the vicinity of the peripheral edge of the upper electrode 14 are charged. The emitted electrons are expelled from the emitter 12 by the dipole of the emitter 12 whose polarity is reversed in the opposite direction (a negative polarity appears on the surface of the emitter 12), as shown in FIG. In the portion 12, electrons are emitted from the portion where the electrons are accumulated through the penetrating portion 20. Of course, electrons are also emitted from the vicinity of the outer periphery of the upper electrode 14. Next, the second electron emission method will be described. First, in the first output period T 1 (first stage) in FIG. 9, a voltage V 3 higher than the reference voltage is applied to the upper electrode 14, and a voltage V 4 lower than the reference voltage is applied to the lower electrode 16. Is applied. In the first output period T 1, preparation for electron emission (for example, polarization of the emitter section 12 in one direction) is performed. In the next second output period T 2 (second stage), the voltage level of the drive voltage V a changes suddenly, that is, a voltage V 4 lower than the reference voltage is applied to the upper electrode 14, When a voltage V 3 higher than the reference voltage is applied to the electrode 16, this time, electric field concentration occurs at the triple junction described above, and primary electrons are emitted from the upper electrode 14 due to this electric field concentration, Of the emitter portion 12, the portion exposed from the through portion 20 and the vicinity of the outer peripheral portion of the upper electrode 14 will collide. As a result, as shown in FIG. 10, secondary electrons (including reflected electrons of the primary electrons) are emitted from the portion where the primary electrons collide. That is, in the initial stage of the second output period T 2, secondary electrons are emitted from the penetration portion 20 and the vicinity of the outer periphery of the upper electrode 14.

In the electron-emitting device 1 OA according to the first embodiment, since the plurality of through portions 20 are formed in the upper electrode 14, each of the through portions 20 and the upper electrode 1 are formed. Electrons are evenly emitted from the vicinity of the outer periphery of 4, reducing variations in the overall electron emission characteristics, facilitating control of electron emission, and increasing electron emission efficiency.

[0079] In the first embodiment, the gap 28 is formed between the flange 26 of the upper electrode 14 and the emitter 12, so that the drive voltage Va is applied. In this case, electric field concentration is likely to occur in the gap 28 portion. This leads to higher efficiency of electron emission, and lower drive voltage (electron emission at a low voltage level) can be realized.

[0080] As described above, in the first embodiment, the upper electrode 14 has the flange portion 26 formed in the peripheral portion of the through portion 20 so that the gap portion 28 described above Combined with the fact that the electric field concentration is increased, Electrons are easily emitted. This leads to a high output and high efficiency of electron emission, and a reduction in the drive voltage Va can be realized. As a result, for example, it is possible to increase the brightness of, for example, a display or a light source configured by arranging a large number of electron emitting elements. In addition, the first electron emission method (method of emitting electrons accumulated in the emitter portion 1 2) described above or the second electron emission method (primary electrons from the upper electrode 14 are caused to collide with the emitter portion 1 2. In any case, the eaves 26 of the upper electrode 14 functions as a gate electrode (control electrode, focus electron lens, etc.), improving the straightness of the emitted electrons. It can be made. This is advantageous in reducing crosstalk when configured as a display electron source.

As described above, in the electron-emitting device 1 OA according to the first embodiment, high electric field concentration can be easily generated, and the number of electron emission locations can be increased. High output and high efficiency can be achieved for emission, and low voltage drive (low power consumption) is also possible.

[0082] In particular, in the first embodiment, at least the upper surface of the emitter portion 12 is formed with irregularities 22 due to dielectric grain boundaries, and the upper electrode 14 is a concave portion at the dielectric grain boundaries. Since the through portion 20 is formed in the portion corresponding to 24, the flange portion 26 of the upper electrode 14 can be easily realized.

[0083] Further, the upper surface of the emitter portion 12, that is, the surface of the convex portion 30 at the dielectric grain boundary (the inner wall surface of the concave portion 2 4), and the lower surface 2 6 a of the flange portion 2 6 of the upper electrode 14 The maximum angle 0 is 1 ° ≤0≤60 °, and the surface of the convex part 30 at the grain boundary of the dielectric of the emitter part 1 2 (inner wall surface of the concave part 2 4) and the upper electrode 1 Since the maximum distance d along the vertical direction between the lower surface 2 6 a of the flange 2 6 of 4 is set to 0 m <d ≤ 1 0 m, the electric field in the gap 28 is The degree of concentration can be further increased, and high output and high efficiency for electron emission and low drive voltage can be efficiently achieved.

Further, in the first embodiment, the penetrating portion 20 has the shape of the hole 32. As shown in Fig. 3, the upper electrode 1 4 and the lower electrode 1 6 of the emitter section 1 2 (See Fig. 2) The part where the polarization is inverted or changed according to the drive voltage V a applied between is the part immediately below where the upper electrode 14 is formed (first part) 4 0 and the through part The portion corresponding to the region from the inner circumference of 20 toward the inner portion of the penetration portion 20 (second portion) 4 2, in particular, the second portion 4 2 is the level of the driving voltage V a and the electric field concentration. It will change depending on the degree. Therefore, in the first embodiment, the average diameter of the holes 32 is set to 0.1 m or more and 10 m or less. Within this range, there is almost no variation in the electron emission distribution emitted through the through-hole 20, and electrons can be emitted efficiently.

[0085] When the average diameter of the holes 32 is less than 0.1 m, the region for accumulating electrons is narrowed and the amount of electrons emitted is reduced. Of course, it is conceivable to provide a large number of holes 32, but there is a concern that the manufacturing cost will increase with difficulty. When the average diameter of the hole 3 2 exceeds 10 m, the ratio of the portion (second portion) 4 2 that contributes to electron emission in the portion exposed from the penetrating portion 20 of the emitter portion 1 2 (occupancy rate) ) Is small, the electron emission efficiency decreases.

[0086] The cross-sectional shape of the flange portion 26 of the upper electrode 14 may be a shape that extends horizontally on both the upper surface and the lower surface as shown in FIG. 3, or as shown in FIG. The lower surface 2 6 a of 6 may be substantially horizontal, and the upper end portion of the flange portion 26 may be raised upward. Further, as shown in FIG. 12, the lower surface 2 6 a of the flange 2 6 may be gradually inclined upward toward the center of the penetrating part 20, or as shown in FIG. The lower surface 2 6 a of the flange portion 26 may be gradually inclined downward toward the center of the penetrating portion 20. The example in Fig. 11 can enhance the function as a gate electrode. In the example in Fig. 13, the gap 28 is narrowed, so that electric field concentration is more likely to occur. High output and high efficiency of emission can be improved.

In the first embodiment, as shown in FIG. 14, in the electrical operation, the capacitor C 1 by the emitter section 1 2 is interposed between the upper electrode 14 and the lower electrode 16. And an aggregate of a plurality of capacitors Ca with each gap 28 formed. That is, multiple capacitors C with each gap 28 a is configured as a single capacitor C 2 connected in parallel with each other. In terms of an equivalent circuit, a capacitor C 1 formed by an emitter 12 is connected in series to a capacitor C 2 formed from an aggregate.

[0088] Actually, the capacitor C1 due to the emitter portion 12 is not directly connected in series to the capacitor C2 due to the aggregate, and the number of through-holes 20 formed in the upper electrode 14 and the overall formation area, etc. The capacitor component connected in series changes in response to.

Here, for example, as shown in FIG.

Assuming that 25% of 1 is connected in series with a capacitor C2 by an aggregate, calculate the capacity. First, since the gap 28 is vacuum, the relative dielectric constant is 1. The maximum gap d of the gap 28 is 0.1 m, the area S of one gap 28 is S = 1 mX 1 m, and the number of the gaps 28 is 10,000. When the dielectric constant of the emitter part 1 2 is 2 000, the thickness of the emitter part 1 2 is 20 m, and the opposing area of the upper electrode 14 and the lower electrode 16 is 20 OZ mX 200 m, the capacitor C by the aggregate C The capacitance value of 2 is 0.885 p F, and the capacitance value of capacitor C 1 by the emitter section 1 2 is 35.4 p F. Then, when the portion connected in series with the capacitor C 2 by the aggregate in the capacitor C 1 by the emitter section 12 is 25% of the total, the capacitance value (condenser by the aggregate) in the portion connected in series The capacitance value including the capacitance value of C2 is 0.805 pF, and the remaining capacitance value is 26.6 pF.

[0090] Since the series-connected part and the remaining part are connected in parallel, the overall capacitance value is 27.5 p F. This capacitance value is 78% of the capacitance value 35.4 p F of the capacitor C 1 by the emitter section 12. That is, the overall capacitance value is smaller than the capacitance value of the capacitor C 1 by the emitter unit 12.

[0091] As described above, the aggregate of the capacitors Ca by the plurality of gaps 28 has a relatively small capacitance value of the capacitor Ca by the gaps 28, and is separated from the capacitor C 1 by the emitter section 12. Pressure, applied voltage Va In most cases, it is applied to the gap 28, and in each gap 28, high output of electron emission is realized.

[0092] Further, the capacitor C 2 by the aggregate has a structure connected in series to the capacitor C 1 by the emitter section 12. Therefore, the overall capacitance value is based on the capacitance value of the capacitor C 1 by the emitter section 12. Becomes smaller. From this, it is possible to obtain desirable characteristics that electron emission is high output and overall power consumption is small.

[0093] Further, in the electron-emitting device 1OA according to the first embodiment, since the glass substrate 11 is used, it is easy to increase the size and reduce the cost of the product. Can be planned. In addition, it is possible to promote a reduction in processing temperature related to the production of the electron-emitting device 1 O A and to reduce the cost of the equipment. Crystallized glass may be used as the glass substrate 11. In this case, unlike general glass, the processing temperature can be in the range of 60 ° C. and 80 ° C., and the degree of freedom in material selection can be expanded.

Next, three modified examples of the electron-emitting device 1 O A according to the first embodiment will be described with reference to FIGS.

First, as shown in FIG. 16, the electron-emitting device 10 A a according to the first modified example has a shape of the penetrating portion 20, in particular, a shape viewed from the upper surface, and is a shape of a notch 44. It is different in that. As the shape of the notch 4 4, a comb-like notch 4 6 in which a large number of notches 4 4 are continuously formed as shown in FIG. 16 is preferable. In this case, it is advantageous to reduce the variation in the emission distribution of the electrons emitted through the through-hole 20 and to efficiently emit electrons. In particular, the average width of the notches 44 is preferably 0.1 m or more and 10 m or less. This average width is the average of the lengths of different line segments orthogonal to the center line of the notches 44.

The electron-emitting device 10 A b according to the second modified example is different in that the shape of the penetrating portion 20, particularly the shape seen from the upper surface, is a slit 48, as shown in FIG. . Here, the slit 48 is a slit whose length in the major axis direction (longitudinal direction) is not less than 10 times the length in the minor axis direction (short direction). Therefore, long axis direction (longitudinal direction ) Is less than 10 times the length in the short axis direction (short direction) can be defined as the shape of the hole 3 2 (see Fig. 4). In addition, the slits 48 include those in which a plurality of holes 32 are connected and connected. In this case, the average width of the slit 48 is preferably 0.1 m or more and 10 m or less. This is because variations in the emission distribution of electrons emitted through the through-hole 20 are reduced, which is advantageous in efficiently emitting electrons. This average width indicates the average length of a plurality of different line segments perpendicular to the center line of the slit 48.

As shown in FIG. 18, the electron-emitting device 10 Ac according to the third modification has a portion corresponding to the penetrating portion 20, for example, a dielectric, on the upper surface of the emitter portion 12. The difference is that the floating electrode 50 exists in the recess 24 of the grain boundary. In this case, since the floating electrode 50 also serves as an electron supply source, a large number of electrons can be emitted to the outside through the through-hole 20 in the electron emission stage (second stage). In this case, the electron emission from the floating electrode 50 may be due to electric field concentration at the ripple junction of the floating electrode 5 O Z dielectric Z vacuum.

Here, characteristics of the electron-emitting device 1 O A according to the first embodiment, in particular, voltage-charge amount characteristics (voltage-polarization amount characteristics) will be described.

The electron-emitting device 1 O A according to the first embodiment is shown in FIG.

19 As shown in the characteristics of 9, draw an asymmetric hysteresis curve with reference voltage = 0 (V).

[0100] This characteristic will be described. First, when a portion of the emitter section 12 where electrons are emitted is defined as an electron emission section, at the point p 1 (initial state) where a reference voltage is applied, the electrons are emitted. It is in a state where almost no electrons are accumulated in the emission part. After that, when a negative voltage is applied, the amount of positive charges of the dipole whose polarization is inverted in the electron emitter 12 increases in the electron emitter, and accordingly, from the upper electrode 14 in the first stage toward the electron emitter. Electron emission occurs and electrons are accumulated. When the level of the negative voltage is increased in the negative direction, a certain negative voltage point p 2 is generated as electrons accumulate in the electron emission portion. The amount of positive charge and the amount of negative charge are in equilibrium, and as the negative voltage level is increased in the negative direction, the amount of accumulated electrons further increases, and the amount of negative charge increases accordingly. The state becomes larger than the amount of charge. At point p3, the electron is saturated. The amount of negative charge here is the sum of the amount of electrons remaining as accumulated and the amount of negative charge of the dipole whose emitter 12 is inverted.

[0101] After that, when the level of the negative voltage is decreased, and when a positive voltage is applied exceeding the reference voltage, the emission of electrons in the second stage starts at point p4. If this positive voltage is increased in the positive direction, the amount of emitted electrons increases, and at point p5, the amount of positive charge and the amount of negative charge are balanced. And at point p6, most of the accumulated electrons are emitted, and the difference between the amount of positive charge and the amount of negative charge becomes almost the same as the initial state. In other words, there is almost no accumulation of electrons, and only the negative charge of the dipole whose emitter 12 is polarized appears in the electron emitter.

[0102] The characteristic parts of this characteristic are as follows.

[0103] (1) When the negative voltage at point p2 where the amount of positive charge and the amount of negative charge are in equilibrium is V1, and the positive voltage at point p5 is V2,

I V 1 | G | V2 |

It is.

[0104] (2) More specifically, 1.5 X | V 1 | <| V2 |.

[0105] (3) The rate of change of the amount of positive charge and the amount of negative charge at point p 2 is expressed as AQ 1

When the rate of change in the amount of positive charge and the amount of negative charge at V 1 and point p 5 is 厶 Q 2ZA V 2,

(△ Q 1ZAV 1)> (AQ2ZAV2)

It is.

[0106] (4) When V 3 is the voltage at which electrons are accumulated and saturated, and V4 is the voltage at which electron emission starts,

1≤ | V4 | V3 | ≤ 1.5

It is. Next, the characteristics of FIG. 19 will be described in terms of voltage-polarization characteristics. In the initial state, the explanation is based on the assumption that the emitter section 12 is polarized in the negative direction, for example, the negative pole of the dipole faces the upper surface of the emitter section 12 (see Fig. 2 OA). To do.

First, as shown in FIG. 19, at a point では p 1 (initial state) to which a reference voltage (for example, OV) is applied, the dipole negative electrode is connected to the emitter section 1 as shown in FIG. 2 is directed to the upper surface of 2, so that almost no electrons are accumulated on the upper surface of the emitter portion 1 2.

[0109] After that, when a negative voltage is applied and the level of the negative voltage is increased in the negative direction, the polarization starts to reverse from around the point where the negative coercive voltage is exceeded (see point p 2 in Fig. 9). All polarizations are reversed at point p3 in Fig. 19 (see Fig. 20B). Due to this polarization inversion, electric field concentration occurs at the triple junction described above, and electron emission from the upper electrode 14 to the emitter section 1 2 occurs in the first stage. For example, the upper electrode 1 of the emitter section 1 2 Electrons are accumulated in a portion exposed from the through portion 20 of 4 and a portion near the peripheral portion of the upper electrode 14 (see FIG. 20C). In particular, electrons are emitted (internal emission) from the upper electrode 14 toward a portion of the emitter portion 12 exposed from the through portion 20 of the upper electrode 14. Then, at point p 3 in Fig. 19, the accumulated state of electrons is saturated.

[01 10] After that, if the level of the negative voltage is decreased, and if a positive voltage is applied exceeding the reference voltage, the charged state on the upper surface of the emitter section 12 is maintained until a certain voltage level is reached. (See Fig. 21 A). When the level of the positive voltage is further increased, a region where the negative pole of the dipole starts to face the upper surface of the emitter section 1 2 occurs just before point p4 in Fig. 19 (see Fig. 21B). After point p 4 in Fig. 19, emission of electrons begins due to the Coulomb repulsive force due to the negative pole of the dipole (see Fig. 21C). If this positive voltage is increased in the positive direction, the amount of emitted electrons increases, and the region where the polarization reverses again from around the point where the positive coercive voltage is exceeded (point 卜 p 5) expands. Accumulation Most of the electrons that have been released are emitted, and the amount of polarization at this time is almost the same as the amount of polarization in the initial state.

[0111] Characteristic portions of the characteristics of the electron-emitting device 1 OA are as follows.

[0112] (A) When negative coercive voltage is v 1 and positive coercive voltage is V 2,

I V 1 | <| V 2 |

It is.

[0113] (B) More specifically, 1.5 X | V 1 |

[0114] (C) The rate of change of polarization when negative coercive voltage V 1 is applied is expressed as Δ q 1 Z 厶

V 1, the rate of change in polarization when a positive coercive voltage V 2 is applied, Δ q 2 を

When V 2

(Δ q 1 V 1)> (Aq 2ZA v 2)

It is.

[0115] (D) When V 3 is the voltage at which electrons are accumulated and saturated, and V 4 is the voltage at which electron emission starts,

1≤ | v 4 les | v 3 | ≤ 1.5

It is.

[0116] Since the electron-emitting device 1OA according to the first embodiment has the above-described characteristics, the electron-emitting device 1OA includes a plurality of electron-emitting devices 1OA arranged according to a plurality of pixels. Each electron-emitting device 1 can be easily applied to a light source that emits a phosphor by emitting electrons from OA and a display that displays an image.

Next, a display and a light source (hereinafter referred to as a display 100 or the like) configured using the electron-emitting device 1 OA according to the first embodiment will be described. In the following description, the unit element of the display is referred to as “pixel”, and the unit element of the light source is referred to as “light emitting element”.

[0118] This display or the like 100 has a large number of electron-emitting devices as shown in FIG.

1 OA is arranged in a matrix or staggered manner corresponding to pixels, and an electron emission device (light emission display unit) 102 according to the present embodiment and the light emission display unit 102 And a driving circuit 10 4 for driving. In this case, one electron-emitting device 1 OA may be assigned per pixel (light-emitting device), or a plurality of electron-emitting devices 1 OA may be assigned per pixel (light-emitting device). In this embodiment, in order to simplify the description, a case where one electron-emitting device 1 OA is assigned per pixel (light emitting device) will be described.

[0119] This drive circuit 1 0 4 is provided with a plurality of row selection lines 1 0 6 for selecting a row for the light emitting display section 1 0 2 and data for the light emitting display section 1 0 2 as well. A plurality of signal lines 1 0 8 for supplying the signal S d are wired.

[0120] Further, the drive circuit 10 04 selectively supplies a selection signal S s to the row selection lines 1 0 6 to sequentially select the electron-emitting devices 1 OA in units of one row 1 1 0 and a signal supply circuit 1 1 which outputs a data signal S d in parallel to the signal line 1 0 8 and supplies the data signal S d to the row selected by the row selection circuit 1 1 0 (selected row). 2 and a signal control circuit 1 1 4 for controlling the row selection circuit 1 1 0 and the signal supply circuit 1 1 2 based on the input video signal SV and synchronization signal Sc.

[0121] The row selection circuit 1 1 0 and the signal supply circuit 1 1 2 are connected to the power supply circuit 1 1 6 (for example, 5 0 and 0), in particular, between the row selection circuit 1 1 0 and the power supply circuit 1 1 6 A pulse power supply 1 1 8 is connected between the negative electrode line and GND (ground). The pulse power supply 1 1 8 outputs a pulsed voltage waveform having a reference voltage (for example, O V) in a charge accumulation period Td, which will be described later, and a voltage (for example, −400 V) in the light emission period Th.

[0122] The row selection circuit 1 1 0 outputs the selection signal S s to the selected row and the non-selection signal Sn to the non-selected row during the charge accumulation period T d. In the row selection circuit 1 1 0, the power supply voltage from the power supply circuit 1 1 6 (for example, 5 0 V) and the voltage from the pulse power supply 1 1 8 (for example, −4 0 0 V) are added to the light emission period Th. Outputs a constant voltage (for example, -3 5 0 V).

The signal supply circuit 1 1 2 has a pulse generation circuit 1 2 0 and an amplitude modulation circuit 1 2 2. The pulse generation circuit 1 2 0 has a constant pulse during the charge accumulation period Td. A pulse signal Sp having a constant amplitude (for example, 50 V) is generated and output, and a reference voltage (for example, OV) is output during the light emission period Th.

[0124] The amplitude modulation circuit 1 2 2 modulates the amplitude of the pulse signal Sp from the pulse generation circuit 1 2 0 according to the luminance level of the pixel (light emitting element) in the selected row during the charge accumulation period T d, Each is output as a data signal S d of a pixel (light emitting element) relating to the selected row, and the reference voltage from the pulse generation circuit 120 is output as it is during the light emission period Th. The timing control and the supply of the luminance level of a plurality of selected pixels (light emitting elements) to the amplitude modulation circuit 12 2 are performed through the signal control circuit 1 14.

[0125] For example, as shown in three examples in Fig. 2 3 A and Fig. 2 3 C, when the luminance level is low, the amplitude of the pulse signal Sp is set to the low level V s I (see Fig. 2 3 A) and the luminance When the level is medium, the amplitude of the pulse signal S p is set to the medium level V sm (see Fig. 23 B). When the luminance level is high, the amplitude of the pulse signal S p is set to the high level V sh ( (See Figure 2 3C). In this example, an example divided into three is shown, but when applied to a display or the like 1 0 0, the pulse signal S p is, for example, 1 2 8 steps depending on the luminance level of the pixel (light emitting element) The amplitude is modulated in steps of 2 and 5 6.

Here, a modified example of the signal supply circuit 1 1 2 will be described with reference to FIG. 2 4 25 C.

As shown in FIG. 24, the signal supply circuit 1 1 2 a according to the modification includes a pulse generation circuit 1 2 4 and a pulse width modulation circuit 1 2 6. In the pulse generation circuit 1 2 4, in the voltage waveform applied to the electron-emitting device 1 OA during the charge accumulation period T d (shown by the solid line in Fig. 25). Generates and outputs a pulse signal Spa whose level changes (indicated by a broken line in Fig. 25A and Fig. 25C), and outputs a reference voltage during the light emission period Th. The pulse width modulation circuit 1 2 6 selects the pulse width W p of the pulse signal Spa from the pulse generation circuit 1 2 4 (see FIG. 25 A and FIG. 25 C) during the charge accumulation period T d. According to the luminance level of the pixel (light emitting element) related to the row And output as a data signal S d of the pixel (light emitting element) for each selected row. During the light emission period Th, the reference voltage from the pulse generation circuit 1 2 4 is output as it is. Also in this case, the timing control and the supply of the luminance level of the selected pixels (light emitting elements) to the pulse width modulation circuit 1 26 are performed through the signal control circuit 1 14.

[0128] For example, as shown in three examples in Figure 25 A and Figure 25 C, when the brightness level is low, the pulse width W p of the pulse signal Spa is shortened, and the substantial amplitude is reduced to the low level V. s I (see Fig. 25 A). When the brightness level is medium, the pulse width W p of the pulse signal Spa is set to the medium length, and the substantial amplitude is set to the medium level V sm ( When the luminance level is high, increase the pulse width W p of the pulse signal Spa to make the actual amplitude high V sh (see Figure 25 C). Here, three examples are shown, but when applied to a display or the like 100 0, the pulse signal Spa is, for example, 1 2 8 steps or 2 5 according to the luminance level of the pixel (light emitting element). Pulse width modulated in 6 steps.

Here, the change in the characteristic diagram when the level of the negative voltage related to the above-described electron accumulation is changed is represented by three amplitude modulations for the pulse signal S p shown in FIGS. 2 3 A and 23 C. And the negative voltage level V s shown in Fig. 2 3 A and Fig. 25 A in relation to the three pulse width modulation examples for the pulse signal Spa shown in Fig. 2 5 A and Fig. 2 5 C. In I, as shown in FIG. 26 A, the amount of electrons stored in the electron-emitting device 1 OA is small. At the negative voltage level V s shown in Fig. 2 3 B and Fig. 2 5 B, as shown in Fig. 2 6 B, the amount of accumulated electrons is medium, and Fig. 2 3 C and Fig. 2 5 At the negative voltage level V sh shown in C, as shown in Fig. 26 C, the amount of accumulated electrons is large and almost saturated.

[0130] However, as shown in these Fig. 2 6 A 2 6 C, the voltage level at the point p 4 where electron emission starts is almost the same. That is, even after the electrons are accumulated, even if the applied voltage changes up to the voltage level shown at point p4, the amount of accumulated electrons is almost unchanged and the memory effect is exhibited. [0131] Further, when the electron-emitting device 1 OA according to the first embodiment is used as a pixel (light emitting device) of a display or the like 100, as shown in FIG. A transparent plate made of, for example, glass or acrylic is disposed above, and a collector electrode made of, for example, a transparent electrode on the back surface (the surface facing the upper electrode 14) of the transparent plate 1 30. 2 is arranged, and phosphor 1 3 4 is applied to the collector electrode 1 3 2. A bias voltage source 1 3 6 (collector voltage V c) is connected to the collector electrode 1 3 2 via a resistor. In addition, the electron-emitting device 10 A is naturally disposed in the vacuum space. The degree of vacuum in the atmosphere is preferably 1 0 ² 1 0 — ^{6 Pa} , more preferably 1 0 — ³ 1 0 — ^{5 Pa} .

[0132] The reason for choosing such a range is that, in low vacuum, (1) because there are many gas molecules in the space, it is easy to generate plasma, and if too much plasma is generated, there will be a lot of positive ions. (2) The emitted electrons collide with gas molecules before they reach the collector electrode 1 3 2 and are sufficiently accelerated by the collector voltage V c This is because the phosphor 1 3 4 may not be sufficiently excited.

[0133] On the other hand, in a high vacuum, electrons are likely to be emitted from the point where the electric field concentrates, but there is a problem that the structure support and the vacuum seal part are large, which is disadvantageous for miniaturization. .

In the example of FIG. 27, the collector electrode 1 3 2 is formed on the back surface of the transparent plate 1 3 0, and the phosphor 1 3 is formed on the surface of the collector electrode 1 3 2 (surface facing the upper electrode 1 4). In addition, as shown in FIG. 28, the phosphor 1 3 4 is formed on the back surface of the transparent plate 1 30 and the collector electrode 1 3 is covered so as to cover the phosphor 1 3 4 2 may be formed.

This is a configuration used in a CRT or the like, and the collector electrode 1 3 2 functions as a metal back. The electrons emitted from the emitter section 1 2 penetrate the collector electrode 1 3 2 and enter the phosphor 1 3 4 to excite the phosphor 1 3 4. Accordingly, the collector electrode 1 3 2 is thick enough to allow electrons to pass through, and is preferably 100 η m or less. The greater the kinetic energy of the electron, the greater the collector electrode 1 3 The thickness of 2 can be increased.

[0136] With such a configuration, the following effects can be obtained.

(A) When the phosphor 1 34 is not conductive, charging (negative) of the phosphor 1 34 can be prevented and the acceleration electric field of electrons can be maintained.

(B) The collector electrode 1 32 reflects the light emitted from the phosphor 1 34, and the light emitted from the phosphor 1 34 can be efficiently emitted to the transparent plate 1 30 side (light emitting surface side).

(C) Excessive collision of electrons with the phosphor 1 34 can be prevented, and deterioration of the phosphor 1 34 and gas generation from the phosphor 1 34 can be prevented.

Next, four experimental examples (first and fourth experimental examples) for the electron-emitting device 1 OA according to the first embodiment are shown.

[0141] In the first experimental example, the electron emission state of the electron-emitting device 10A is observed. That is, as shown in FIG. 29A, a write pulse Pw having a voltage of −7 OV is applied to the electron-emitting device 1 OA to accumulate electrons in the electron-emitting device 1 OA, and then 28 OV A lighting pulse P h having a voltage was applied to emit electrons. The electron emission state was measured by detecting the light emission of phosphor 1 34 with a light receiving element (photodiode). The detected waveform is shown in Fig. 29B. The duty ratio of the write pulse Pw and the lighting pulse Ph was 50%.

[0142] From this first experimental example, it can be seen that light emission started in the middle of the rise of the lighting pulse Ph, and light emission ended at the initial stage of the lighting pulse Ph. Therefore, even if the duration of the lighting pulse Ph is shortened, it is considered that there is no effect on light emission. This leads to a shortening of the high voltage application period, which is advantageous in reducing power consumption.

[0143] The second experimental example shows how the amount of electrons emitted from the electron-emitting device 1 OA varies depending on the amplitude of the write pulse Pw shown in FIG. The change in the amount of emitted electrons was measured by detecting the light emission of the phosphor 134 with a light receiving element (photodiode), as in the first experimental example. The experimental results are shown in Fig. 31.

[0144] In Figure 3 1, the solid line A shows the characteristics when the amplitude of the lighting pulse P h is 200 V and the amplitude of the write pulse Pw is changed from -1 OV to -8 OV. The solid line B shows the characteristics when the amplitude of the lighting pulse Ph is 35 OV and the amplitude of the write pulse Pw is changed from -1 OV to -8 OV.

As shown in FIG. 31, when the write pulse P w is changed from −20 V to −40 V, it can be seen that the emission luminance changes almost linearly. In particular, when the amplitude of the lighting pulse Ph is 3550 V and 20 OV, the dynamic range of the emission luminance change with respect to the write pulse Pw is broad in the case of 35 OV. It can be seen that this is advantageous in improving brightness and improving contrast in image display. This tendency seems to be more advantageous as the amplitude of the lighting pulse Ph is increased in the range until the emission luminance is saturated with respect to the amplitude setting of the lighting pulse Ph. Therefore, it is preferable to set the optimal value.

[0146] The third experimental example shows how the amount of electrons emitted from the electron-emitting device 1OA changes with the amplitude of the lighting pulse Ph shown in Fig. 30. The change in the amount of emitted electrons was measured by detecting the light emission of phosphor 1 34 with a light receiving element (photodiode), as in the first experimental example. The experimental results are shown in Figure 32.

[0147] In Figure 3 2, the solid line C shows the characteristics when the amplitude of the write pulse P w is set to -4 OV and the amplitude of the lighting pulse P h is changed from 5 OV to 40 OV. Shows the characteristics when the amplitude of the write pulse P w is −7 OV and the amplitude of the lighting pulse P h is changed from 50 V to 400 V.

[0148] As shown in Fig. 32, it can be seen that when the lighting pulse Ph is changed from 10 0 V to 3 0 0 V, the emission luminance changes almost linearly. In particular, when the amplitude of the write pulse P w is -4 OV and -7 OV, it is lit when -70 V, and the dynamic range of the emission luminance change with respect to Luth P h is wide. Therefore, it can be seen that it is advantageous for improving the brightness and contrast of the image display. This tendency seems to be more advantageous as the amplitude (in this case, absolute value) of the write pulse P w is increased in the range until the emission luminance is saturated with respect to the amplitude setting of the write pulse P w. Even in this case, it is preferable to set the optimum value in relation to the withstand voltage and power consumption of the signal transmission system. That's right.

[0149] The fourth experimental example shows how the amount of electrons emitted from the electron-emitting device 1 OA varies depending on the level of the collector voltage Vc shown in Fig. 27 or Fig. 28. The change in the amount of emitted electrons was measured by detecting the emission of phosphor 1 34 with a light receiving element (photodiode), as in the first experimental example. The experimental results are shown in Figure 33.

[0150] In Fig. 33, the solid line E shows the characteristics when the level of the collector voltage V c is 3 kV and the amplitude of the lighting pulse Ph is changed from 8 OV to 50 OV. The solid line “ The characteristics when the level of the voltage V c is 7 kV and the amplitude of the lighting pulse Ph is changed from 8 OV to 50 OV are shown.

[0151] As shown in Fig. 33, when the collector voltage Vc is set to 7 kV, the dynamic range of the light emission luminance change with respect to the lighting pulse Ph is wider than when 3 kV is used. It can be seen that it is advantageous in improving brightness and contrast in This tendency seems to be more advantageous as the level of the collector voltage V c increases, but in this case as well, it is preferable to set the optimum value in relation to the withstand voltage and power consumption of the signal transmission system.

Here, one driving method of the above-described display 100 will be described with reference to FIGS. 34 and 35. FIG. FIG. 34 typically shows the operation of a pixel (light emitting element) in one row and one column, two rows and one column, and n rows and one column. The electron-emitting device 1 OA used here has a coercive voltage V 1 at point p 2 in FIG. 19 of −2 OV, for example, coercive voltage V 2 at point p 5 is +7 OV, and voltage at point p 3 V 3 has a characteristic of -50 V and voltage V 4 at point p 4 has a characteristic of +5 OV.

Furthermore, as shown in FIG. 34, when the display period of one image is one frame, one charge accumulation period Td and one light emission period Th are included in the one frame. In addition, one charge accumulation period Td includes n selection periods T s. Since each selection period T s becomes the selection period T s of the corresponding row, n−1 rows that do not correspond become the non-selection period T n. [0154] Then, in this driving method, all the electron-emitting devices 1 0 in the charge accumulation period T d

By scanning A and applying a voltage corresponding to the brightness level of each pixel (light-emitting element) corresponding to each of the plurality of electron-emitting elements 1 OA corresponding to the pixel (light-emitting element) to be turned ON (light-emitting target) A plurality of electron-emitting devices corresponding to the ON target pixel (light-emitting device) 1 Charges (electrons) corresponding to the luminance level of the pixel (light-emitting device) corresponding to each OA are accumulated, and the next light emission period T Apply a constant voltage to all electron-emitting devices 1 OA in h, and the brightness of each pixel (light-emitting device) corresponding to each of the plurality of electron-emitting devices 1 OA corresponding to the ON target pixel (light-emitting device) The amount of electrons is emitted according to the level, and the pixel (light emitting element) to be turned on emits light.

More specifically, as shown in FIG. 35, first, in the selection period T s of the first row, a selection signal S of, for example, 50 V is applied to the row selection line 1 0 6 of the first row. For example, a non-selection signal 5 of 0 is supplied to the row selection lines 1 0 6 of the other rows. Among the pixels (light emitting elements) in the first column, the voltage of the data signal S d supplied to the signal line 10 8 of the pixel (light emitting element) to be turned on (light emitting element) is OV or more and 3 OV or less. The voltage is in the range and according to the luminance level of the corresponding pixel (light emitting element). OV when the brightness level is maximum. The modulation according to the luminance level of the data signal Sd is performed through the amplitude modulation circuit 12 2 shown in FIG. 22 and the pulse width modulation circuit 1 26 shown in FIG.

[0156] Thus, the electron emitter 1 corresponding to each pixel (light emitting element) to be turned ON in the first row 1 OA has a space between the upper electrode 14 and the lower electrode 16 according to the luminance level. -A voltage of 5 OV or more and-2 OV or less is applied. As a result, each electron-emitting device 1 OA described above accumulates electrons according to the applied voltage. For example, the electron emission element corresponding to the pixel (light emitting element) in the first row and the first column is, for example, at the maximum luminance level, and thus is in the state of the point p 3 in the characteristic of FIG. The maximum amount of electrons is accumulated in the portion exposed from the through portion 20 of the upper electrode 14.

[0157] An electron-emitting device 1 corresponding to a pixel (light-emitting device) indicating OFF (quenching) 1 The voltage of the data signal S d supplied to the OA is, for example, 50 V. As a result, 0 is applied to the electron-emitting device 10 corresponding to the OFF target pixel (light-emitting device). The state of the characteristic point p 1 in Fig. 19 is entered, and no electrons are accumulated.

[0158] After the supply of the data signal Sd to the first row is completed, the selection signal Ss of 5 OV is applied to the row selection line 106 of the second row in the selection period Ts of the second row. Then, the non-selection signal Sn of 0 V is supplied to the row selection line 106 of the other row. In this case as well, between the upper electrode 14 and the lower electrode 16 of the electron-emitting device 1 OA corresponding to the pixel (light-emitting device) that should be turned on (light-emitting) is -5 OV or more depending on the luminance level. A voltage of 2 OV or less is applied. At this time, a voltage of OV or more and 5 OV or less is applied between the upper electrode 14 and the lower electrode 16 of the electron emission device 1 OA corresponding to the pixel (light emitting device) in the non-selected state, for example, the first row. However, since this voltage is a voltage that does not reach point 4 in the characteristics of Fig. 19, the electron emission corresponding to the pixel (light emitting element) that should be turned ON (light emitting) in the first row Element 1 Electrons are not emitted from the OA. That is, the pixel (light emitting element) in the first row in the non-selected state is not affected by the data signal S d supplied to the pixel (light emitting element) in the second row in the selected state.

[0159] Similarly, in the selection period T s of the n-th row, the 50 V selection signal S s is supplied to the row selection line 106 of the n-th row, and 0 is supplied to the row selection line 106 of the other rows. V non-selection signal Sn is supplied. Also in this case, the electron emission element 1 corresponding to the pixel (light emitting element) to be turned ON (light emitting element) 1 -5 OV or more between the upper electrode 14 and the lower electrode 16 of the OA, depending on the luminance level. A voltage of 2 OV or less is applied. At this time, the electron-emitting device 1 corresponding to each pixel (light-emitting device) in one row (n-1) in the non-selected state 1 OV is between OV and 5 OV between the upper electrode 14 and the lower electrode 16 of the OA Electrons are emitted from the electron-emitting device 1 OA corresponding to the pixel (light-emitting device) that should be turned on (light-emitting device) among these non-selected pixels (light-emitting devices). There is no.

[0160] When the selection period T s of the n-th row has elapsed, the light emission period T h is entered. This light emission In the period T h, a reference voltage (for example, OV) is applied to the upper electrode 14 of the all electron-emitting device 1 OA through the signal supply circuit 1 1 2, and the lower electrode 16 of the all-electron emitting device 1 OA is -350 V voltage (pulse power supply 1 1 8-400 V + row selection circuit 1 1 0 power supply voltage 50 V) is applied. As a result, a high voltage (+350 V) is applied between the upper electrode 14 and the lower electrode 16 of the all-electron emission element 1 OA. All the electron-emitting devices 1 OA are in the state of the point p 6 in the characteristic of FIG. 19 respectively, and as shown in FIG. 21C, from the part where the electrons are accumulated in the emitter section 12, Electrons are emitted through the penetration 20. Of course, electrons are also emitted from the vicinity of the outer periphery of the upper electrode 14.

[0161] That is, an electron-emitting device corresponding to a pixel (light-emitting device) to be turned on (light-emitting device)

Electrons are emitted from 1 OA, and the emitted electrons are guided to the collector electrode 1 32 corresponding to these electron-emitting devices 1 OA to excite the corresponding phosphor 1 34 and emit light. As a result, an image is displayed from the surface of the transparent plate 130.

[0162] Similarly, for each frame, in the charge accumulation period Td, electrons are accumulated in the electron emitter 1 OA corresponding to the pixel (light emitting element) to be turned on (light emitting element), and accumulated in the light emitting period Th. By emitting the emitted electrons and causing them to emit fluorescent light, a moving image or a still image is displayed from the surface of the transparent plate 130.

Thus, the electron-emitting device according to the first embodiment has a plurality of electron-emitting devices 1 OA arranged in accordance with a plurality of pixels (light-emitting devices), and each electron-emitting device Element 1 It becomes easy to apply to a display or the like that displays an image by emitting electrons from OA.

[0164] For example, as described above, during the charge accumulation period Td in one frame, all the electron-emitting devices are scanned, and a plurality of electron-emitting devices 1 OA corresponding to the ON target pixels (light-emitting devices) are obtained. By applying a voltage according to the luminance level of the corresponding pixel (light emitting element), the brightness of the pixel (light emitting element) corresponding to each of the plurality of electron emitting elements 1 OA corresponding to the pixel (light emitting element) to be turned on Depending on the level A plurality of electron emission elements corresponding to the ON target pixel (light emission element) by applying a constant voltage to all the electron emission elements 1 OA in the next light emission period Th. 1 The amount of electrons corresponding to the brightness level of the corresponding pixel (light emitting element) can be emitted from each OA, and the pixel (light emitting element) to be turned on can emit light.

[0165] In the first embodiment, for example, the relationship between the voltage V 3 at which electrons are accumulated and saturated and the voltage V 4 at which the emission of electrons starts is 1≤ | V 4 | Z | V 3 | ≤ 1.5.

[0166] Normally, for example, the electron-emitting devices 1 OA are arranged in a matrix, the electron-emitting devices 1 OA are selected in units of one row in synchronization with the horizontal scanning period, and the electron-emitting devices 1 in the selected state are selected. When the data signal S d corresponding to the luminance level of each pixel (light emitting element) is supplied to OA, the data signal S d is also supplied to the non-selected pixel (light emitting element).

[0167] When the electron-emitting device 10 A in the non-selected state emits, for example, electrons due to the influence of the data signal Sd, there is a problem in that the degradation of the image quality of the display image causes a decrease in contrast.

However, since the first embodiment has the characteristics described above, the voltage level of the data signal S d supplied to the selected electron-emitting device 1 OA is changed from the reference voltage to the voltage V 3. Even if the voltage relationship is set so that, for example, a signal having a polarity opposite to that of the data signal Sd is supplied to the non-selected electron-emitting device 1 OA, the non-selected state This pixel (light emitting element) is not affected by the data signal S d to the pixel (light emitting element) in the selected state. That is, the amount of electrons accumulated in each pixel (light emitting element) accumulated in the selection period T s of each pixel (light emitting element) (the amount of charge of the emitter section 1 2 in each electron emitting element 1 OA) is the next light emitting period. As a result, the memory effect in each pixel (light emitting element) can be realized, and high luminance and high contrast can be achieved.

[0169] On the other hand, in this display 1 0 0, all charge storage period T d The necessary charge is stored in the electron-emitting device 1 OA, and the voltage required for electron emission is applied to all the electron-emitting devices 1 OA in the subsequent light emission period Th, so that Electrons are emitted from a plurality of electron-emitting devices 1 OA corresponding to (light-emitting devices), and the pixels (light-emitting devices) to be turned on emit light.

[0170] Normally, when a pixel (light emitting element) is composed of the electron emitting element 1 OA, it is necessary to apply a high voltage to the electron emitting element 1 OA in order to cause the pixel (light emitting element) to emit light. Therefore, when accumulating electric charges during scanning to the pixel (light emitting element) and further emitting light, it is necessary to apply a high voltage over a period of displaying one image (for example, one frame). There is a problem that power consumption increases. In addition, the circuit for selecting each electron-emitting device 1 OA and supplying the data signal S d needs to be a circuit corresponding to a high voltage.

However, in this example, after the electric charges are accumulated in all the electron-emitting devices 1 OA, a voltage is applied to all the electron-emitting devices 1 OA, and the pixels corresponding to the electron-emitting devices 10 A to be turned on (Light emitting element) is made to emit light.

Therefore, the period T h during which the voltage for electron emission (emission voltage) is applied to all the electron-emitting devices 1 OA is naturally shorter than one frame, and FIG. 29A and FIG. As can be seen from the first experimental example shown in 29 B, the period during which the emission voltage is applied can be shortened, compared with the case where charge accumulation and light emission are performed during scanning of the pixel (light-emitting element). Power consumption can be greatly reduced.

[0173] Further, the electron emission element 1 Td during which charge is accumulated in OA, and the pixel to be turned on

The electron emission element 1 corresponding to the (light emitting element) 1 OA is separated from the period T h during which electrons are emitted, so that the circuit for applying a voltage corresponding to the luminance level to each electron emission element 1 OA is designed to be driven at a low voltage. be able to.

[0174] Further, the data signal corresponding to the image and the selection signal SsZ non-selection signal Sn in the charge accumulation period Td need to be driven for each row or column, as seen in the above-described embodiment. In addition, since the driving voltage may be several tens of ports, an inexpensive multi-output driver used in a fluorescent display tube or the like can be used. Meanwhile, light emission period T In h, the voltage that sufficiently discharges electrons may be higher than the drive voltage. However, since all the pixels to be turned on (light-emitting elements) need to be driven at once, a circuit component with multiple outputs Do not need. For example, it is only necessary to have a drive circuit with only one output composed of high breakdown voltage discrete components, which is advantageous in terms of cost and cost. The drive voltage and discharge voltage can be reduced by reducing the thickness of the emitter section 12. Therefore, for example, the driving voltage can be set to several ports by setting the film thickness.

[0175] Furthermore, according to this driving method, the second stage of electron emission not based on row scanning is performed at the same time for all pixels (light emitting elements) separately from the first stage based on row scanning. It is easy to secure the light emission time regardless of the screen size, and the brightness can be increased. In addition, since images are displayed on the screen all at once, it is possible to display moving images without false contours or image blurring.

Next, an electron-emitting device 1 OB according to the second embodiment will be described with reference to FIG.

The electron-emitting device 1OB according to the second embodiment has substantially the same configuration as the electron-emitting device 1OA according to the first embodiment described above, as shown in FIG. The upper electrode 14 is made of the same material as the lower electrode 16, the upper electrode 14 is thicker than 10 m, and the through-hole 20 is etched (wet etching, dry It is characterized in that it is artificially formed using etching), lift-off, and laser. As the shape of the penetrating portion 20, the shape of the hole 32, the shape of the notch 44, and the shape of the slit 48 can be adopted as in the first embodiment described above.

Furthermore, the lower surface 26 6 a of the peripheral portion 26 of the through portion 20 in the upper electrode 14 is gradually inclined upward toward the center of the through portion 20. This shape can be easily formed by using, for example, lift-off.

[0179] Also in the electron-emitting device 1OB according to the second embodiment, the above-described first

1 Electron-emitting device according to one embodiment 1 As with OA, high electric field concentration is easily achieved In addition, the number of electron emission locations can be increased, high output and high efficiency can be achieved for electron emission, and low voltage drive (low power consumption) is also possible. Also in this case, since the glass substrate 11 is used, it is possible to easily increase the size of the plate and to reduce the product cost.

[0180] Further, like the electron-emitting device 1OBa according to the first modification shown in Fig. 37, the floating electrode 50 is provided on the upper surface of the emitter section 12 corresponding to the through-hole 20. May be present.

[0181] Further, like the electron-emitting device 1OBb according to the second modification shown in FIG. 38, an electrode having a substantially T-shaped cross section is formed as the upper electrode 14. May be.

Also, like the electron-emitting device 10 0 Be according to the third modification shown in FIG. 39, the shape of the upper electrode 14, particularly, the peripheral portion 2 of the through portion 20 of the upper electrode 14 6 may be raised. In this case, the film material to be the upper electrode 14 may include a material that is gasified during the firing process. Thereby, in the firing process, the material is gasified, and as a result, a large number of through portions 20 are formed in the upper electrode 14, and the peripheral portion 26 of the through portion 20 is lifted. Become.

[0183] It should be noted that the electron-emitting device according to the present invention is not limited to the above-described embodiment, and can of course have various configurations without departing from the gist of the present invention.

Claims

The scope of the claims

[1] a first electrode (1 6) formed on a glass substrate (1 1);

An emitter portion (12) made of a dielectric film formed on the first electrode (16);

A second electrode (1 4) formed on the emitter section (1 2), and a drive voltage (Va) for electron emission is the first electrode (16) and the second electrode Applied between the electrodes (1 4)

At least the second electrode (1 4) has a plurality of through portions (20) from which the emitter portion (1 2) is exposed,

Of the second electrode (14), the surface (26a) facing the emitter (12) in the peripheral portion (26) of the penetrating portion (20) is the emitter portion (12). An electron-emitting device characterized in that the electron-emitting device is spaced apart from).

[2] The electron-emitting device according to claim 1,

Of the emitter portion (1 2), at least the surface on which the second electrode (1 4) is formed is formed with irregularities (22) due to dielectric grain boundaries,

The electron emission element, wherein the second electrode (14) has the penetrating portion (20) formed in a portion corresponding to the concave portion (24) in the grain boundary of the dielectric.

[3] The electron-emitting device according to claim 1 or 2,

The second electrode (1 4) is composed of an aggregate (17) of a plurality of scale-like substances (15) or a conductive substance (15) containing a scale-like substance (15). An electron-emitting device characterized by being an assembly (2 1) of 1 9).

[4] The electron-emitting device according to any one of claims 1 to 3,

The first electrode (1 6), the emitter part (1 2), and the second electrode (1 4) are at a temperature lower than the softening point of the glass substrate (1 1), and the glass substrate (1 1 ) An electron-emitting device characterized in that a film is directly formed thereon.

[5] The electron-emitting device according to any one of claims 1 to 3,

The emitter part (1 2) has a temperature higher than the softening point of the glass substrate (1 1). An electron-emitting device comprising: a sheet formed by bonding to the glass substrate (1 1).

An electron-emitting device having a plurality of electron-emitting devices (1 OA) formed on a glass substrate (1 1),

The electron-emitting device (1 OA) is

A first electrode (1 6) formed on the glass substrate (1 1) and an emitter section (1 the emitter section (1) made of a dielectric film formed on the first electrode (1 6) 2) a second electrode (1 4) formed thereon, and a drive voltage (Va) for electron emission is the first electrode (1 6) and the second electrode (1 4) ) Applied between

Of the second electrode (14), the surface (26a) facing the emitter (12) in the peripheral portion (26) of the penetrating portion (20) is the emitter portion (12). An electron-emitting device characterized in that it is spaced apart from

An electron emission device according to claim 6,

A transparent plate (1 30) disposed opposite to the surface of the glass substrate (1 1) where the emitter (1 2) is formed in the electron emission device;

Electrode (1 32) for forming an electric field between the transparent plate (1 30) and the electron emitter (1 OA) in the electron emission device on a surface facing the emitter (1 2) When,

A phosphor (1 34) formed on the electrode (1 32),

A display characterized in that electrons emitted from the electron-emitting device (1 OA) collide with the phosphor (1 34) to excite the phosphor (1 34) to emit light.

An electron emission device according to claim 6,

Of the glass substrate (1 1), the emitter (1 2) in the electron emission device ) And a transparent plate (1 30) arranged facing the surface on which

A phosphor (1 34) formed on the electrode (1 32),

A light source characterized in that electrons emitted from the electron-emitting device (1 OA) collide with the phosphor (1 34) to excite the phosphor (1 34) to emit light.