KR20070078930A - Electron emission device and electron emission display device using the same - Google Patents

Abstract

An electron emission device and an electron emission display device using the same are provided to activate frequently a getter by using a driving voltage by installing a getter at driving electrodes in an outline of active region. A pair of substrates(10,12) are used for composing a vacuum vessel. A plurality of electron emission elements are formed at one of two substrates. A plurality of driving electrodes(20) are formed on the substrate in order to control electrons emitted from the electron emission unit. An end of each driving electrode is extended to the outside of the vacuum vessel. A getter(26) is attached to the driving electrodes in the inside of the vacuum vessel in order to receive a voltage necessary for activation from the driving electrode. The driving electrodes include scan electrodes(22) and data electrodes. The getter is attached to one electrode for receiving a large voltage of the scan electrodes and the data electrodes.

Description

ELECTRON EMISSION DEVICE AND ELECTRON EMISSION DISPLAY DEVICE USING THE SAME

1 is a partially cutaway perspective view of an electron emission display device according to an exemplary embodiment of the present invention.

2 is a partially exploded perspective view of a field emission array (FEA) type electron emission display device according to an embodiment of the present invention.

3 is a partial cross-sectional view of a field emission array (FEA) type electron emission display device in accordance with one embodiment of the present invention.

4 is a partial cross-sectional view of a surface conduction emission (SCE) type electron emission display device according to an embodiment of the present invention.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron emission device, and more particularly, to an electron emission device and an electron emission display device using the same, which may reactivate the getter at any time after fabricating the vacuum container by changing the mounting position of the getter.

In general, electron emission elements may be classified into a method using a hot cathode and a cold cathode according to the type of electron source.

Here, the electron-emitting device using the cold cathode is a field emitter array (FEA) type, a surface conduction emission type (SCE) type, a metal-insulation layer-metal Metal (MIM) type and Metal-Insulator-Semiconductor (MIS) type are known.

The electron emitting device is arranged in an array on one of the first and second substrates constituting the vacuum container to form an electron emitting device, and the electron emitting device is combined with a light emitting unit provided on the other substrate to emit electrons. Configure a display device.

The electron emission device has electron emission portions and a plurality of driving electrodes that function as scan and data electrodes to emit an intended amount of electrons in units of pixels, and the electron emission display device fluoresces electrons emitted from the electron emission portion. The layer is excited to have a predetermined light emission or display function.

The first substrate and the second substrate are integrally bonded to each other by a sealing member, and then the inner space is evacuated to a vacuum of approximately 10 ⁻⁶ Torr to form a vacuum container together with the sealing member. The vacuum container can ensure excellent emission characteristics and lifetime characteristics of the electron emitting portion when the inside thereof is kept in a high vacuum state.

Therefore, the electron emission display device has a getter mounted inside the chamber attached to either one of the first substrate and the second substrate, or inside the chamber attached to one of the substrates. The degree of vacuum is increased by absorbing and removing residual gas inside the vessel.

On the other hand, since outgassing occurs continuously in the internal structure facing the vacuum area after the vacuum container is produced, the degree of vacuum decreases in the process of using the product after completion of the product.

By the way, the conventional getter is not reused after being activated once in the manufacture of the vacuum container, it is not possible to prevent a decrease in the degree of vacuum generated during use. As a result, the conventional electron emission display device has a problem that the degree of vacuum decreases as the use time increases, so that the emission efficiency decreases and the lifetime of the electron emission unit is shortened.

Accordingly, an object of the present invention is to provide an electron emission device and an electron emission display device using the same, which can prevent a decrease in vacuum degree by frequently reactivating a getter after fabricating a vacuum container.

In order to achieve the above object, the present invention,

A pair of substrates constituting the vacuum vessel, electron emission portions formed on any one of the pair of substrates, and a drive provided to one substrate to control electron emission of the electron emission portion, the end of which extends out of the vacuum vessel An electron emitting device comprising electrodes and a getter attached to the drive electrodes inside the vacuum vessel to receive a voltage required for activation from the drive electrode.

The driving electrodes include scan electrodes and data electrodes, and the getter may be attached to an electrode to which a large voltage is applied among the scan electrodes and the data electrodes.

When the electron emitting device is of field emission array type, the getter may be attached to the scan electrodes.

The getter may be installed outside the active area in which the electron emitters are located, and may be formed of a non-evaporable getter.

In addition, the present invention, in order to achieve the above object,

A pair of substrates constituting the vacuum vessel, electron emission portions formed on any one of the pair of substrates, and a drive provided to one substrate to control electron emission of the electron emission portion, the end of which extends out of the vacuum vessel Electrodes, a getter attached to the driving electrodes inside the vacuum vessel to receive a voltage required for activation from the driving electrodes, fluorescent layers formed on the other one of the pair of substrates, and located on one surface of the fluorescent layers. Provided is an electron emission display device comprising an anode electrode.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a partially cutaway perspective view of an electron emission display device according to an exemplary embodiment of the present invention.

Referring to the drawings, the electron emission display device includes a first substrate 10 and a second substrate 12 which are disposed in parallel to each other at predetermined intervals. Sealing members 14 are disposed at the edges of the first substrate 10 and the second substrate 12 to bond the two substrates, and the inner space is evacuated with a vacuum of approximately 10 ⁻⁶ Torr so that the first substrate 10 The second substrate 12 and the sealing member 14 constitute a vacuum container.

On the opposite side of the first substrate 10 to the second substrate 12 is provided an electron emitting unit 16 consisting of electron emitting elements to form an electron emitting device together with a vacuum container, and the electron emitting device is provided. 2 is combined with the light emitting unit 18 provided on the substrate 12 to form an electron emission display device.

The electron emission unit 16 includes electron emission portions (not shown) and scan electrodes 22 and data electrodes 24 as driving electrodes 20 for controlling electron emission of the electron emission portion, The intended amount of electrons is emitted toward the light emitting unit 18 pixel by pixel. The scan electrodes 22 and the data electrodes 24 have their ends extending out of the vacuum chamber to receive the corresponding driving voltages from a driving circuit portion (not shown).

Each of the electron emission elements constituting the electron emission unit 16 has a field emitter array (FEA) type, a surface conduction emission type (SCE) type, and metal-insulation using a cold cathode electron source. It can be made of either a metal-insulator-metal (MIM) type or a metal-insulator-semiconductor (MIS) type.

The light emitting unit 18 includes a fluorescent layer and an anode electrode for electron beam acceleration. The fluorescent layer is composed of red, green, and blue fluorescent layers to display a full color screen, and the anode electrode is applied with a direct current voltage of hundreds to thousands of volts to transfer electrons emitted from the electron emission part to the fluorescent layer. It acts as a puller.

Also inside the vacuum vessel is a getter 26 for adsorbing residual gas after exhaust. The getter 26 may be non-evaporative and is activated by receiving a predetermined voltage from the electrode. The electron emission display device of the present embodiment does not have a separate electrode for activating the getter, and the getter 26 is disposed at a predetermined portion of the driving electrode 20 to obtain a getter 26 with a driving voltage applied to the driving electrodes 20. ) Is activated.

The getter 26 may be attached to any one of the scan electrodes 22 and the data electrodes 24, and may be attached to the electrodes having a higher applied voltage. For example, when the electron emission unit 16 is a field emission array (FEA) type, the getter 26 may be attached to the scan electrodes 22 and activated by the scan driving voltage applied to the scan electrodes 22. .

The getter 26 is located outside the active area where the electron emitters are located so as not to affect the electron emission action of the electron emitter. Although one getter is illustrated in the drawing, the number and position of the getters 26 are not limited to the illustrated example and can be variously modified.

As the getters are provided in the scan electrodes 22 outside the active region in this manner, the getters 26 are frequently activated by the scan driving voltage whenever the user uses the display device. Therefore, the gas adsorbed on the surface of the getter 26 after the exhaust is diffused to increase the adsorption efficiency of the getter 26, and the getter 26 again adsorbs the residual gas by outgassing to suppress the decrease in the degree of vacuum.

Hereinafter, the internal structure of the field emission array (FEA) type electron emission display device will be described with reference to FIGS. 2 and 3, and the internal structure of the surface conduction emission type (SCE) type electron emission display device will be described with reference to FIG. 4. Explain.

2 and 3, in a field emission array (FEA) type electron emission display device, the electron emission unit 16 ′ is formed along a direction perpendicular to each other with the first insulating layer 28 interposed therebetween. 30 and gate electrodes 32 and electron emitters 34 formed on the cathode electrode 30.

When the intersection region of the cathode electrodes 30 and the gate electrodes 32 is defined as a pixel region, electron emission portions 34 are formed in each pixel region over the cathode electrodes 30, and the first insulating layer 28 is formed. And openings 281 and 321 corresponding to the electron emission parts 34 are formed in the gate electrodes 32 and the gate electrodes 32 to expose the electron emission parts 34 on the first substrate 10.

The electron emission part 34 may be made of materials emitting electrons when a electric field is applied in a vacuum, such as a carbon-based material or a nanometer (nm) size material. The electron emission part 34 may include, for example, carbon nanotubes, graphite, graphite nanofibers, diamonds, diamond-like carbons, fullerenes (C ₆₀ ), silicon nanowires, or combinations thereof. Screen printing, direct growth, chemical vapor deposition or sputtering can be applied.

On the other hand, the electron emission unit may be formed of a tip structure having a pointed tip mainly made of molybdenum (Mo) or silicon (Si).

In addition, the second insulating layer 36 and the focusing electrode 38 may be positioned on the gate electrodes 32 and the first insulating layer 28. The focusing electrode 38 forms one opening 381 in each pixel region to collectively focus electrons emitted from one pixel region, or one opening corresponding to each of the electron emission units 34 to form each opening. Electrons emitted from the emitter 34 may be individually focused. The first case is shown in the figure.

The light emitting unit 18 ′ is formed between the fluorescent layer 40, for example, red, green, and blue fluorescent layers 40R, 40G, and 40B positioned at arbitrary distances from each other, and between each fluorescent layer 40. It includes a black layer 42 positioned to increase the contrast of the screen. The fluorescent layer 40 is disposed such that a fluorescent layer of one color corresponds to each crossing region of the cathode electrode 30 and the gate electrode 32.

An anode electrode 44 formed of a metal film such as aluminum (Al) is formed on the fluorescent layer 40 and the black layer 42. The anode 44 receives the high voltage necessary for accelerating the electron beam from the outside to maintain the fluorescent layer 40 in a high potential state, and visible light emitted toward the first substrate 10 of the visible light emitted from the fluorescent layer 40. Is reflected toward the second substrate 12 to increase the brightness of the screen.

The anode electrode may be formed of a transparent conductive film such as indium tin oxide (ITO). In this case, the anode is positioned on one surface of the fluorescent layer 40 and the black layer 42 facing the second substrate 12. Moreover, the structure which forms simultaneously the above-mentioned metal film and a transparent conductive film as an anode electrode is also possible.

In addition, spacers 46 (see FIG. 3) are disposed between the first substrate 10 and the second substrate 12 to support the compressive force applied to the vacuum container and to keep the distance between the two substrates constant. The spacers 46 are positioned corresponding to the black layer 42 so as not to invade the fluorescent layer 40.

The field emission array (FEA) type electron emission display device of the above-described configuration supplies a predetermined voltage to the cathode electrodes 30, the gate electrodes 32, the focusing electrode 38, and the anode electrode 44 from the outside. Drive.

For example, any one of the cathode electrodes 30 and the gate electrodes 32 receives a scan driving voltage to serve as scan electrodes, and the other electrodes receive a data driving voltage to serve as data electrodes. In addition, the focusing electrode 38 receives a voltage required for electron beam focusing, for example, 0 V or a negative DC voltage of several to several tens of volts, and the anode electrode 44 requires a voltage for accelerating the electron beam, for example, several hundred to several thousand volts. DC voltage of is applied.

Then, in the pixels where the voltage difference between the cathode electrode 30 and the gate electrode 32 is greater than or equal to the threshold, an electric field is formed around the electron emission part 34 to emit electrons therefrom. The emitted electrons are focused to the center of the electron beam bundle while passing through the opening 381 of the focusing electrode 38, and are attracted by the high voltage applied to the anode electrode 44 to impinge on the fluorescent layer 40 of the corresponding pixel to emit light. Let's do it.

Referring to FIG. 4, in a surface conduction emission (SCE) type electron emission display device, first electrodes 48 and second electrodes 50 are disposed on the first substrate 10 and spaced apart from each other. The first conductive thin film 52 and the second conductive thin film 54 which are located close to each other while covering a portion of the surface of each electrode are formed in the field 48 and the second electrodes 50.

An electron emission unit 56 is formed between the first conductive thin film 52 and the second conductive thin film 54 to be connected to the conductive thin films, and the electron emission unit 56 is formed through the first electrodes. Electrical connection with the 48 and the second electrode 50.

The first electrode 48 and the second electrode 50 may be formed of various conductive materials. The first conductive thin film 52 and the second conductive thin film 54 may include nickel (Ni), gold (Au), It consists of a thin film of fine particles using a conductive material such as platinum (Pt) and palladium (Pd). The electron emission section 56 is preferably formed of graphite carbon, a carbon compound, or the like, and carbon nanotubes, graphite, graphite nanofibers, diamonds, diamond-like carbons, C, as in the field emission array (FEA) type described above. ₆₀ , silicon nanowires, and combinations thereof.

On the other hand, the light emitting unit 18 "provided on the second substrate 12 is made the same as in the above-described field emission array type (FEA), and thus detailed description thereof will be omitted.

In the above structure, when a predetermined driving voltage is applied to the first electrode 48 and the second electrode 50, the electron emission unit 56 is formed through the first conductive thin film 52 and the second conductive thin film 54. As the current flows in a direction parallel to the surface of the surface conduction electron emission, the emitted electrons are attracted to the second substrate 12 by the high voltage applied to the anode electrode 44 and correspond to the fluorescent layer of the corresponding pixel ( 40) to emit light.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications and changes can be made within the scope of the claims and the detailed description of the invention and the accompanying drawings. Naturally, it belongs to the range of.

As described above, in the electron emission display device according to the present invention, the getter is installed on the drive electrodes outside the active area, and thus the getter may be activated at any time by using the driving voltage when the display device operates. Therefore, the electron emission display device according to the present invention can suppress the deterioration of the degree of vacuum and ensure excellent emission characteristics and lifetime characteristics of the electron emission portion for a long time.

Claims (7)

A pair of substrates constituting the vacuum container; Electron emission parts formed on one of the pair of substrates; Drive electrodes provided on the one substrate to control electron emission of the electron emission unit, and an end portion of which is extended out of the vacuum container; And A getter attached to the driving electrodes inside the vacuum container to receive a voltage required for activation from the driving electrode; Electron emitting device comprising a. The method of claim 1, The driving electrodes include scan electrodes and data electrodes, And the getter is attached to an electrode to which a large voltage is applied among the scan electrodes and the data electrodes. The method of claim 2, And the getter is attached to the scan electrodes, wherein the electron emitting device is of a field emission array type. The method of claim 1, And the getter is installed outside the active area in which the electron emitting portions are located. The method of claim 1, And the getter is non-evaporative. An electron emitting device according to any one of claims 1 to 5; Fluorescent layers formed on the other one of the pair of substrates; And An anode located on one surface of the fluorescent layers Electron emission display device comprising a. The method of claim 6, A black layer located between the fluorescent layers; And a spacer disposed corresponding to the black layer between the pair of substrates.

Images