JPH07245071A - Display device - Google Patents

Abstract

PURPOSE:To prevent the generation of unnecessary gas, and achieve long life of a display device by installing a getter member to receive electron beams radiated from cathode electrodes on the outer side of a picture element display part. CONSTITUTION:An insulation film 12 having cavities 12a is formed on an Si substrate 11, and a cathode array is formed of cathode electrodes 14 comprising micro-chips on the substrate 11 in the cavities 12a. A getter member 17 is installed on the outer side of a fluorescent screen comprising phosphor 16 formed on a glass plate 15 to receive electron beams radiated from the electrodes 14 without radiating electron beams to the fluorescent screen among the electrodes 14. The electron beams are thus radiated to the member 17 constantly during usage of a display to keep an active condition by its heat, thereby the generation of unnecessary gas is prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat panel display, and more particularly to a flat panel display type display device using a micro cathode array.

[0002]

2. Description of the Related Art Conventionally, a flat panel display using a field emission type cathode array of micron order is known as shown in FIG. As shown in FIG. 3, in this conventional flat panel display, a silicon dioxide (SiO ₂ ) film 22 having a cavity 22 a is formed on a silicon substrate 21. This Si around the cavity 22a
Molybdenum (Mo) and niobium (N) are formed on the O ₂ film 22.
A gate electrode 23 made of b) or the like is formed, and a molybdenum cone-shaped cathode electrode 24 is formed on the Si substrate 21 inside the cavity 22a.

A fluorescent screen having a fluorescent material 26 formed on a flat glass plate 25 faces in parallel with the Si substrate 21 on which the cathode array composed of a large number of cathode electrodes 24 is formed. The space between the Si substrate 21 and the Si substrate 21 is sealed while being kept in a vacuum. The flat panel display is evacuated in the manufacturing process and sealed in a state where the vacuum is maintained. However, when the flat panel display is actually used, the electron beam rushes into the phosphor screen and gas is released. Due to this gas, the degree of vacuum in the tube deteriorates. Due to the deterioration of the degree of vacuum, ion bombardment occurred inside the tube, destroying the gate electrode and the cathode electrode, and causing the display to malfunction.

[0004]

The conventional flat panel display has a problem that the gas generated by the electron beam penetrating the phosphor screen destroys the gate electrode and the cathode electrode and causes the display to malfunction. .

The present invention has been made in view of the above problems, and it is an object of the present invention to provide a display device in which there is no fear of destruction of the gate electrode or the cathode electrode due to gas generation and the reliability of display operation is improved. To aim.

[0006]

In order to achieve the above object, the present invention provides a plurality of cathode electrodes formed on a substrate and an electron beam emitted from the cathode electrodes which is arranged so as to face the substrate. A transparent substrate on the surface of which a pixel display region made of a fluorescent substance is formed, a low-voltage region formed between the substrate and the transparent substrate, and an electron beam emitted from the cathode electrode formed outside the pixel display unit. A getter member for receiving the display device is provided.

In particular, it is desirable that the getter member is arranged at a position where the electron beam according to the image signal is irradiated, because the getter member can be activated with high efficiency during use. Further, it is desirable that the getter member is tantalum, titanium, zirconium, niobium simple substance or an alloy thereof in order to prolong the life.

Further, the surface of the getter member on which the electron beam enters is made of a non-getter material such as nickel or stainless steel, and the opposite surface is made of a material having a getter effect such as tantalum, titanium or zirconium. This is desirable from the standpoint of preventing re-emission of the gettered gas and enhancing the getter efficiency without deteriorating the getter ability.

The low pressure region is preferably a vacuum because electrons are efficiently emitted from the cathode electrode, but a small amount of gas, for example, an inert gas such as argon may be filled.

[0010]

With the above structure, the getter member is constantly irradiated with the electron beam while the display is in use, and the heat keeps the active state, so that unnecessary gas generation can be prevented and the low pressure region can be maintained even during a long use time. Can be kept in a good low pressure state, and the life of the display device can be maintained for a long time.

[0011]

EXAMPLES The present invention will be described below with reference to examples. (Embodiment 1) FIG. 1A is a sectional view showing a flat panel display type display device according to the present invention, and an enlarged view in the circle is FIG. 1B.

As shown in FIG. 1, in the flat panel display according to this embodiment, for example, a vertical 120
An insulating film 12 such as a SiO ₂ film having a cavity 12a is formed on a conductive flat silicon substrate 11 having a size of 150 mm, a width of 150 mm, and a thickness of 1 mm. The insulating film 1 around the cavity 12a
A gate electrode 13 made of, for example, molybdenum is formed on the surface 2.

Further, the Si inside the cavity 12a is
A cathode electrode 14 made of a microchip is formed on the substrate 11. A cathode array is formed by these many cathode electrodes 14. In this example, the Si on which the cathode array was formed
A fluorescent screen in which a phosphor 16 is formed on a glass plate 15 is provided so as to face the substrate 11. Here, the pixel screen is composed of a phosphor screen as a pixel display region made of a phosphor that receives an electron beam emitted from the cathode array. In this embodiment, the fluorescent screen has a length of 93 m.
It is formed in the part of m and 121 mm in width. A vacuum region is formed between the Si substrate 11 and the glass transparent substrate 15 as a low voltage region.

Further, on the outside of the fluorescent screen, 1 in FIG.
A getter member shown by 7 is attached so as to receive an electron beam emitted from the cathode electrode 14 of the cathode electrode 14 which does not irradiate the fluorescent screen with the electron beam. Here, the outside of the pixel display area refers to an area that is the outer periphery of the pixel display area when the display device is viewed from above the paper surface of FIG.

The getter member will be described in more detail. This getter member is made of a zirconium plate material having a thickness of 7 μm, has a width of 5 mm and a length of 95 mm, and is attached to both sides of the fluorescent screen as described above. The width of the getter member 17 is set to be substantially the same as the width of the video signal not displayed on the screen.

The cathode array, the fluorescent screen portion and the getter member 17 thus constructed use a vacuum sealing member 18 in the drawing to form a vacuum region which is a low pressure region between the substrate 11 and the transparent substrate 15 and form a vacuum. Complete the device.

Next, a method of manufacturing the flat panel display according to this embodiment having the above-mentioned structure will be described. As shown in FIG. 1, first, an insulating film 12 such as a SiO ₂ film is formed on a Si substrate 11 by, for example, a thermal oxidation method, a CVD method, or a sputtering method, and then, on the insulating film 12, for example, a sputtering method or an electron is used. A metal film such as molybdenum or niobium for forming a gate electrode is formed by a beam evaporation method.

Next, a resist pattern (not shown) having a shape corresponding to the gate electrode 13 to be formed is formed on this metal film by lithography. Next, the gate electrode 13 is formed by etching the metal film by using the resist pattern as a mask by a wet etching method or a dry etching method.

Thereafter, the insulating film 12 is etched by wet etching or dry etching using the resist pattern and the gate electrode 13 as a mask to form a cavity 12a.

Next, after removing the resist pattern, electron beam evaporation is performed from a direction inclined at a predetermined angle with respect to the substrate surface to form a peeling layer made of, for example, aluminum or nickel on the gate electrode. Then, for example, molybdenum is deposited as a material for forming a cathode by an electron beam evaporation method from a direction perpendicular to the substrate surface.
As a result, the Si substrate 11 inside the cavity 12a is
A cathode 14 is formed on top.

Next, the peeling layer is removed together with the metal film formed thereon by the lift-off method. Next, a method of manufacturing the getter member 17 will be described. A zirconium plate material having a wall thickness of 7 μm was formed into a width of 5 mm and a length of 95 mm, and
^The member is activated by heat treatment at 1300 ° C. in a vacuum device having a vacuum degree of ⁻⁵ Pa or less.

Next, the getter member 17 is attached to the vacuum sealing member 18 as shown in FIG. 1 (b). A lead terminal (not shown) is connected to the getter member 17 so that a voltage can be electrically applied from the outside of the display.

Thereafter, as shown in FIG. 1, the screen portion 16 coated with the phosphor and the vacuum sealing member 18 are attached to the Si substrate 11 and electrostatically adhered in a vacuum device to obtain a desired flat panel. Complete the display.

Next, an operation example of this flat panel display will be described. The video signal is generated by the cathode electrode 14 and the gate electrode 13 formed by the simple matrix method.
Entered in. Considering the cathode electrode 14 as a reference, a gate voltage of +100 V is applied in the highest brightness state. In the fluorescent screen portion, + 400V is applied to a transparent electrode (not shown) such as ITO. The amount of electrons emitted from the cathode is modulated by the voltage of the gate electrode. The electrons are guided by the electric field of the fluorescent screen and enter the fluorescent screen to cause the phosphor to emit light.

Next, the action of the getter will be described. + 400V is applied to the getter member 17. Therefore, the electrons emitted from the cathode electrode 14 always strike the getter member 17 with energy of 400 eV according to the amount of the video signal. This electron impact causes the getter member 17 to reach 200
It reaches a temperature of ~ 300 ° C. By controlling the temperature to this temperature, the getter material 17 is always kept in the activated state, and the vacuum degree in the tube is always kept in a good state.

As described above, according to this embodiment, the getter is always irradiated with the electron beam during use of the display and kept active due to its heat, so that the getter material 17 is not provided. Compared to display devices,
A good vacuum state can be maintained even during a long use time, and stable display operation can be maintained for a long time.

Further, since this getter member is not of the flash type, there is no harmful effect such as electrical leakage between the electrodes. In order to solve this problem, flash type getters are used in cathode ray tubes and the like. That is, this is a method in which a getter in which a ring made of barium alloy is packed in a ring such as stainless steel is heated by high frequency heating to deposit barium metal on the tube wall to form an active getter surface. With such a method, the vacuum in the tube can be maintained for a long time, but in the case of a flat panel display, there is no place to attach the flash type getter and a place to deposit the vapor. Even if there is some place, such a gettering agent is a conductive substance and therefore leaks between the electrodes, which is not preferable. In this embodiment, by selecting a place where the getter member is attached to the outside of the pixel display area, a getter action in a flat panel type display device can be surely provided, which is a completely new structure display which has never existed before. A device can be provided. (Embodiment 2) In the following embodiment, the same parts as those in Embodiment 1 are designated by the same reference numerals, and detailed description thereof will be omitted. Although the getter member is made of a zirconium material in the first embodiment, the getter member is made of tantalum, titanium or niobium alone or an alloy thereof (including a zirconium alloy). This is the difference from Example 1. The structure is similar to that shown in FIG. Also in this embodiment, the same effect as that of the first embodiment can be expected, and further, there is an effect of extending the life. (Third Embodiment) In the first and second embodiments, the case where the getter member is made of a single material has been described.
As shown in FIG. 2, the surface of the getter member on which the electron beam is incident is made of a non-gettering material 27 ₁ such as nickel or stainless steel, and the opposite surface is a material having a gettering effect such as tantalum, titanium or zirconium. If a structure made of 27 ₂ is used, a better effect can be expected.

The reason is that when the getter member is made of a single material, the gas adsorbed in the vicinity of the surface of the getter member due to the incidence of the electron beam is re-emitted even if the amount is small. As a measure against this, if the side on which the electron beam is made incident is made of a non-gettering substance, the above problems will be eliminated. The getter having such a structure can be generally manufactured as a clad material, but can also be manufactured by a plating method or a sputtering method. Also in this embodiment, the first embodiment
Of course, it has the same effect as.

[0029]

According to the present invention, there is no fear of damaging the gate electrode or the cathode electrode due to gas generation, and the reliability of display operation can be improved.

[Brief description of drawings]

FIG. 1 is a sectional view of a first embodiment of the present invention.

FIG. 2 is a sectional view of a third embodiment of the present invention.

FIG. 3 is a sectional view of a conventional display device.

[Explanation of symbols]

 11 ... Si substrate 12 ... Insulating film 13 ... Gate electrode 14 ... Cathode 15 ... Glass substrate 16 ... Phosphor 17 ... Getter member 18 ... Vacuum sealing member

Front page continuation (72) Inventor Shuichi Uchigo 33 33, Isogocho, Isogo-ku, Yokohama Ceremony Company Toshiba Technical Research Institute

Claims (1)

[Claims] 1. A transparent substrate having a plurality of cathode electrodes formed on a substrate, and a pixel display region formed on a surface thereof, the pixel display region being composed of a phosphor arranged to face the substrate and receiving an electron beam emitted from the cathode electrode. And a low voltage region formed between the substrate and the transparent substrate, and a getter member formed outside the pixel display unit for receiving an electron beam emitted from the cathode electrode. .