JP2000195425A - Manufacture of image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To operate an electron emission characteristic stably for a long hours, and aim elongation of life, by activating a non-vaporizing type getter plural times before and after a baking process of an airtight container in which an electron emission element, an image forming member, the non-vaporizing type getter, and a vaporizing type getter, and thereafter by activating the vaporizing type getter. SOLUTION: After exhausting activated gas in an airtight container 100 sufficiently, a current is sent to current-sending introduction terminals 2, 3 of a non-vaporizing getter 1, and a current-sending heating treatment is executed at a prescribed temperature as long as a prescribed time, to thereby execute activation. Then, the airtight container 100 is heated at a prescribed warm-up rate up to a prescribed temperature, and a baking degassing treatment is executed and retained as long as a prescribed time. After executing baking, the container 100 is cooled at a prescribed rate to a room temperature. The non-vaporizing getter 1 is given again the current-sending heating treatment at a prescribed temperature as long as a prescribed time and activated, by sending a current to the current-sending introduction terminals 2, 3. Thereafter, a vaporizing type getter 4 is induction-heated, and Ba is evaporated and activated, and then a part of an exhaust pipe 11 is sealed. Hereby, prolongation of life of a surface conduction type electron emission element 22 can be aimed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an image forming apparatus using an electron-emitting device, and more particularly to a method for manufacturing an airtight container.

[0002]

2. Description of the Related Art Conventionally, as electron-emitting devices, a thermionic electron-emitting device and a cold cathode electron-emitting device are known.
Field emission type (hereinafter referred to as “FE type”) cold cathode electron emission devices
That. ), Metal / insulating layer / metal type (hereinafter “MIM”)
Type ". ) And surface conduction electron-emitting devices.

As an example of the FE type, WPDyke & W.W.Dolan,
“Field emission”, Advance in Electoron Physics, 8,8
9 (1956) or CASpindt, “PHYSICAL Properties of
thin-film field emission cathodes with molybdeniu
m cones ", J. Appl. Phys., 47, 5248 (1976).

As an example of the MIM type, CAMead, “Operati
on of Tunnel-Emission Devices ", J. Appl. Phys., 32, 646
(1961) are known.

Examples of the surface conduction electron-emitting device type include:
MIElinson, Recio Eng. Electron Phys., 10, 1290, (196
5) are disclosed.

[0006] The surface conduction electron-emitting device utilizes the phenomenon that electron emission occurs when a current flows through a small-area thin film formed on a substrate in parallel with the film surface. Examples of the surface conduction electron-emitting device include a device using an SnO ₂ thin film by Elinson et al. And a device using an Au thin film.
[G. Dittmer: “Thin Solid Films”, 9,317 (1972)], In ₂
O ₃ / SnO ₂ by thin film [M.Hartwell and CGFo
nstak: “IEEE Trans. ED Conf.” 519 (1975)], based on carbon thin film [Hisashi Araki et al .: Vacuum, Vol. 26, No. 1,
22 (1983)].

[0007] Flat panel display devices that emit phosphors by electron beams generated from these cold cathode electron-emitting devices have been developed.

The display device requires an ultra-high vacuum to stably operate the cold-cathode electron-emitting devices for a long time. Therefore, a substrate having a plurality of electron-emitting devices and a phosphor at a position facing the substrate are provided. The substrate is sealed by a method described later across a frame to form a vacuum-tight container.

In fact, as described above, in order to form an electron-emitting device in an airtight container and maintain it as an image display device, the inside of the airtight container is evacuated through an exhaust pipe connected to the airtight container. After the device is evacuated to a vacuum and subjected to a process of forming an electron source in the hermetic container or an activation process, the baking process of maintaining the hermetic container at a high temperature of 300 ° C. to 350 ° C. for several hours or more is performed. Perform sufficient degassing of the interior.

Thereafter, the temperature of the airtight container is lowered to room temperature, and the evaporative getter containing Ba as a main component, which is disposed outside the image display area in the airtight container, is heated or heated at a high frequency, thereby evaporating the Ba material to obtain the getter. A film is formed (hereinafter, referred to as getter flash). Thereafter, the exhaust pipe is sealed by heating and melting, and the exhaust device and the airtight container are separated. The vacuum in the airtight container is maintained by the getter film.

Further, a manufacturing method for maintaining the inside of a vacuum-tight container at an ultra-high vacuum has been proposed in Japanese Patent Application Laid-Open No. 7-302545. The manufacturing method disclosed in this publication includes a step of introducing and holding a gas into the display device while baking the inside of the display device after evacuation and a step of evacuating the display device. Is repeated several times, the gas adsorbed inside can be easily released, the gas adsorbed in the display device can be reduced, and the inside of the display device should be maintained at an ultra-high vacuum. It is what it was.

[0012]

However, conventionally,
The following problems occur in the vacuum process for maintaining the vacuum by the evaporable getter as described above.

The pressure P in the hermetic container is expressed as P = Q / S by the amount Q of gas released from the vacuum surface and the effective pumping speed S. The effective pumping speed is determined by the shape of the airtight container, the position of the getter, and the pumping speed of the getter. That is, when the shape of the hermetic container, the position of the getter, and the exhaust speed of the getter are determined, it is necessary to reduce the amount Q of gas released from the hermetic container in order to reduce the vacuum inside the hermetic container as much as possible. .

By increasing the effective pumping speed S during baking, the pressure P in the hermetic container after baking can be reduced.

[0015] However, the conventional evaporable getter has a problem in that the exhaust capability is lowered at high temperatures, and thus it cannot be used as an exhaust pump after sealing.

Further, when activating the evaporative getter, the inside of the airtight container is temporarily contaminated, so that it is effective to increase the effective pumping speed S as much as possible.

In a flat panel image display using a field emission type electron source, it is necessary to reduce impurities such as water, oxygen and CO as much as possible in order to stably operate the electron emission characteristics of the electron source. Therefore, there is a problem in that the electron emission characteristics of the electron source do not operate stably due to impurities generated in the sealing step of the hermetic container, and the life is reduced.

It is an object of the present invention to provide a method of manufacturing an image forming apparatus having an electron-emitting device which operates stably for a long time without the above-mentioned problems.

[0019]

According to a first aspect of the present invention, there is provided a method of manufacturing an image forming apparatus including an electron-emitting device, a phosphor, an exhaust pipe, a non-evaporable getter, and an evaporable getter. A method of manufacturing an image display device having an airtight container includes a step of activating the non-evaporable getter a plurality of times and a step of activating the evaporable getter.

According to the present invention, there is provided a method of manufacturing an image forming apparatus including an electron-emitting device, an image forming member, a non-evaporable getter, and an airtight container having an evaporable getter, wherein a vacuum exhaust device connected to the airtight container is provided. By performing a degassing process of the evaporable getter while exhausting,
Activating the non-evaporable getter; baking the hermetic container at a high temperature; activating the non-evaporable getter again; activating the evaporable getter; The method includes the steps of sealing a container and activating the non-evaporable getter again.

(Operation) According to the method of manufacturing an image forming apparatus of the present invention, in the method of manufacturing an image display apparatus having an airtight container having an electron-emitting device, a phosphor, an exhaust pipe, a non-evaporable getter and an evaporable getter. The non-evaporable getter is characterized in that it can be activated a plurality of times and that the exhaust characteristics can be maintained at high temperatures.

Therefore, by activating the non-evaporable getter before baking at a high temperature after evacuation, the effective pumping speed S of the hermetic container during baking can be increased.

After the baking, the pumping speed of the non-evaporable getter has decreased, but by activating again, the pumping speed can be largely recovered.

Further, when the exhaust pipe is sealed, water, oxygen, etc., which are generated when the material constituting the exhaust pipe exceeds the softening point, are suppressed from being adsorbed to the airtight container, and the exhaust pipe is activated in advance. Since the airtight container is adsorbed by the non-evaporable getter, the inside of the airtight container is prevented from being recontaminated in the step of sealing the exhaust pipe, and a high vacuum is quickly reached and the high vacuum is maintained.

Further, before the step of sealing the exhaust pipe, a vacuum exhaust device connected to the airtight container via the exhaust pipe and the activated non-evaporable getter are provided.
According to the method for manufacturing an image display device of the present invention, which has a step of heating and degassing while evacuating, a high vacuum is more effectively achieved.

In order to prevent the inside of the hermetic container from being recontaminated when the evaporative activation of the evaporable getter is performed, a vacuum exhaust device connected to the hermetic container via an exhaust pipe and an activation are performed again. According to the method of manufacturing an image forming apparatus of the present invention in which the effective pumping speed S is increased by the non-evaporable getter, a high vacuum is more effectively achieved.

It is more effective to degas by heating the evaporable getter at a temperature equal to or lower than the evaporating temperature before activating the non-evaporable getter for the first time.

In addition, maintaining the high vacuum becomes easy by activating the non-evaporable getter again after the evaporative activation of the evaporable getter.

The method includes a step of activating the non-evaporable getter a plurality of times while evacuating by a vacuum exhaust device connected to the airtight container via an exhaust pipe, and a step of activating the evaporable getter.

According to the method of manufacturing an image forming apparatus of the present invention, since the inside of the hermetic container is maintained at a high vacuum, the life of image forming members such as electron-emitting devices and phosphors is extended,
An image forming apparatus having a long life is provided.

[0031]

(Embodiment 1) An image display apparatus of the present invention is shown in FIG.
Then, the manufacturing method will be described with reference to FIG.

FIG. 2A is a schematic perspective view of the image display device used in this embodiment, and a part of the panel is cut away to show the internal structure.

FIG. 2B is a schematic plan view of the image display device used in the present embodiment, and is an example of an arrangement diagram of the non-evaporable getter 1 and the evaporable getter 4. Reference numerals 2 and 3 are current introduction terminals for supplying current to the non-evaporable getter. 5
Is to prevent the getter material from entering the image area when the evaporable getter material is evaporated by the shielding plate.

In the figure, 25 is a rear plate, 26 is a support frame, 27 is a face plate, and the airtight container 10 for keeping the inside of the display panel at a vacuum by 25 to 27 is used.
0 is formed. When assembling the airtight container 100, it is necessary to seal the members in order to maintain sufficient strength and airtightness for joining the members.

In the drawing, reference numerals 11 and 12 denote exhaust pipes for connecting to a vacuum exhaust device when evacuating the airtight container to a vacuum. Further, these exhaust pipes are also used as a gas introduction pipe for an activation gas in an activation step generated during a process step. In this embodiment, a miniature gauge (total pressure gauge) (not shown) was attached to the end of the exhaust pipe 11 in order to evaluate the effectiveness of this embodiment based on the pressure in the panel.

In FIG. 1, reference numeral 1 denotes a non-evaporable getter for assisting vacuum evacuation of the airtight container and for maintaining a vacuum in the airtight container after sealing the exhaust pipe. In the figure, reference numerals 2 and 3 denote current introduction terminals for supplying current to the non-evaporable getter. In the present embodiment, a non-evaporable getter mainly containing Ti and made of Zr, V and Fe is used, but a non-evaporable getter mainly containing Zr may be used.

The main component is Ti used in the present embodiment.
FIG. 4 shows the H ₂ O adsorption characteristics of the non-evaporable getter composed of r, V and Fe. The vertical axis indicates the exhaust speed, and the horizontal axis indicates the exhaust amount (adsorption amount). The measurement was performed by the throughput method. In the figure, the temperature of the non-evaporable getter is set to room temperature, 150 ° C., 3
The characteristics at a temperature of 00 ° C. are shown. According to this, it can be seen that the adsorption rate and the adsorption amount of the non-evaporable getter increase as the temperature increases. That is, it was confirmed that the non-evaporable getter employed in the present example had good exhaust characteristics at high temperatures.

The non-evaporable getter is at 300 ° C.
After baking for 5 hours, reactivation was performed again at 750 ° C., and the exhaust characteristics at room temperature showed characteristics equivalent to those of the initial stage. Ba was used as the evaporable getter 4 shown in FIG.

On the rear plate 25, N × M surface conduction electron-emitting devices 22 are formed. (N and M are positive integers of 2 or more and are appropriately set according to the target number of display pixels.)

In the N × M surface conduction electron-emitting devices, simple matrix wiring is performed by M row-directional wirings 23 (also referred to as lower wirings) and N column-directional wirings 24 (also referred to as upper wirings). I have.

Next, description will be made with reference to FIG. FIG. 3 is a schematic diagram showing the configuration of the surface conduction electron-emitting device 22.
FIG. 3A is a plan view, and FIG. 3B is a cross-sectional view. FIG.
In the figure, 31 is a substrate, 32 and 33 are device electrodes, 34 is a conductive thin film, and 35 is an electron emitting portion.

While the airtight container is evacuated to a vacuum through the exhaust pipe 11, the conductive thin film 3 is passed through the device electrodes 32 and 33.
By subjecting the conductive thin film 4 to a forming treatment, the conductive thin film is locally destroyed, deformed, or altered to form an electron emitting portion 35 in an electrically high-resistance state. When the pressure becomes 10 ⁻³ Pa or less, an ascent is introduced into the hermetic container through the exhaust pipe 11 as an activating gas by about 1 Pa, and an activation step for remarkably improving the emission current is performed by the above-described element electrode 32 of the surface conduction electron-emitting device. ,
By applying a voltage to 33 and passing a current through the element,
The above-described electron emission unit 35 is activated.

On the lower surface of the face plate 27,
A phosphor 28 as an image forming member is formed. Since the present embodiment is a color display device, phosphors of three primary colors of red, green, and blue used in the field of CRT are separately applied to a portion of the fluorescent film 28.

A metal back 29 known in the field of CRTs is provided on the surface of the fluorescent film 28 on the rear plate side. The purpose of providing the metal back 29 is to improve the light efficiency by mirror-reflecting a part of the light emitted from the fluorescent film 28, to protect the fluorescent film 28 from negative ion collision, and to reduce the electron beam acceleration voltage. It may be used as an electrode for application, or may serve as a conductive path for the excited electrons of the fluorescent film 28.

The metal back 29 is formed by forming a fluorescent film 28 on the face plate substrate 27, smoothing the fluorescent film 28, and vacuum-depositing Al thereon. When a low-voltage fluorescent film is used as the fluorescent film 28, the metal back 29 is not used.

Although not used in the present embodiment, for the purpose of applying an accelerating voltage and improving the conductivity of the fluorescent film, for example, an I.D.
A transparent conductive film such as TO may be provided.

Also, Dox1 to Doxm and Doy1
ＤDoyn and Hv are electric connection terminals of an airtight container provided for electrically connecting the display panel to an electric circuit (not shown). Dox1 to Doxm are connected to the row wiring 23 of the multi-electron beam source and Doy1 to Doy.
n is electrically connected to the column wiring 24 of the multi-electron beam source, and Hv is electrically connected to the metal back 29 of the face plate.

The image display device to which the manufacturing method of the present invention is applied has been described.

Next, a method for manufacturing the image display device of the present invention will be described with reference to FIG.

(Preparation of Rear Plate) (R-1) The blue plate glass was washed, and the lower wiring 23 was formed by screen printing on the rear plate on which a silicon oxide film was formed by a sputtering method. Next, the lower wiring 23 and the upper wiring 24
An interlayer insulating film was formed between them. Further, the upper wiring 24 was formed. Next, device electrodes 32 and 33 connected to the lower wiring 23 and the upper wiring 24 were formed. (R-2) Next, a conductive thin film 34 made of PdO was formed by a sputtering method and then patterned to obtain a desired form. (R-3) Frit glass for fixing the support frame was formed at a desired position by printing.

Through the above steps, a rear plate on which a surface conduction electron-emitting device having a simple matrix wiring, an adhesive for a support frame, and the like were formed.

(Preparation of Face Plate) (F-1) A phosphor and a black conductor were formed on a blue plate glass substrate by a printing method. A smoothing treatment was performed on the inner surface of the fluorescent film, and then Al was deposited by using a vacuum evaporation method or the like to form a metal back. (F-2) Frit glass for fixing the support frame was formed at a desired position by a printing method.

Through the above steps, the phosphor in which the phosphors of the three primary colors are arranged in stripes, the adhesive for the support frame, and the like were formed on the face plate.

(Preparation of Airtight Container by Sealing Rear Plate and Face Plate) (FR-1) The rear plate is held on a hot plate on an X, Y, and θ adjustment stage and sealed while aligning the face plate. Raise the temperature of the rear plate and face plate to the arrival temperature. Although the sealing temperature is determined by the frit glass, the sealing temperature was 410 ° C. in this example. At the stage when the temperature is raised to the sealing temperature,
The support frame is brought into contact with the adjustment plate of X, Y, and θ while adjusting the position of the rear plate and the face plate, and is held for 10 minutes while being pressurized. When the temperature was lowered by 100 ° C., the alignment was stopped, the stage was set free, and the temperature was lowered to room temperature.

(Preparation of Electron Emitting Element by Vacuum Process) (S-1) Airtight container 100 prepared as described above.
The exhaust pipe 11 on the face plate is connected to a vacuum exhaust device, and the inside of the airtight container 100 is exhausted to a vacuum. At this time, a total pressure gauge is attached to the exhaust pipe 12. (S-2) When the pressure in the airtight container becomes 0.1 Pa or less, the external terminals Dox1 to Doxm and Doy1 to Don.
yn, a voltage is applied to the electron-emitting device and the conductive thin film 3
4 was subjected to a forming step. (S-3) Subsequently, the pressure in the airtight container is 1 × 10 ⁻³ P
a, acetone is introduced as an activating gas through the exhaust pipe 11 into the airtight container at a pressure of 1 Pa.
A voltage was applied to the electron-emitting device through ox1 to Doxm and Doy1 to Doyn to perform an activation process.

(Degassing Step in Airtight Container) FIG. 1 shows a flowchart of the degassing step in the airtight container. (D-1) After exhausting the activation gas sufficiently, the non-evaporable getter 1 is activated. An electric current was passed through the current introducing terminals 2 and 3 of the non-evaporable getter 1 to activate the non-evaporable getter 1. The activation temperature of the non-evaporable getter is determined by the non-evaporable getter.
An electric heating process was performed for 15 minutes. (D-2) Next, the airtight container heating device was set, and the airtight container was baked and degassed. The baking temperature was 300 ° C. The heating rate was 2 ° C. per minute. (D-3) After the temperature of the airtight container reaches 300 ° C, 1
It was kept for 0 hour and baked. (D-4) The airtight container was cooled at a rate of 2 ° C. per minute and cooled to room temperature. (D-5) The power introduction terminal 2 of the non-evaporable getter 1 again
An electric current was passed through and 3 to activate the non-evaporable getter. The activation temperature of the non-evaporable getter is 75 in this embodiment.
An electric heating treatment was performed at 0 ° C. for 15 minutes. (D-6) The evaporable getter is heated by induction heating, and B
a was evaporated and activated. (D-7) Remove the airtight container heating device and remove the exhaust pipe 11
Was melted by heating to seal.

As a comparative example, FIG. 5 shows a flowchart of the degassing step in the case where the degassing step in the airtight container is performed according to the following procedure.

(Comparative Example 1) (Degassing Step in Airtight Container) FIG. 5 shows a flowchart of the degassing step in the airtight container. (D-1) The airtight container was baked and degassed.
The baking temperature was 300 ° C. Heating rate is 2 ℃ per minute
And (D-2) The temperature of the airtight container was kept at 300 ° C. for 10 hours, and baking was performed. (D-3) After the completion of the baking, the temperature of the airtight container was lowered at 2 ° C. per minute and cooled to room temperature. (D-4) heating the evaporable getter by induction heating,
a was evaporated and activated. (D-5) Remove the airtight container heating device, and remove the exhaust pipe 11
Was melted by heating to seal.

The pressure inside the airtight container 24 hours after the completion of the sealing is 50% in the airtight container prepared in this embodiment.
It stabilized at a lower value than the comparative example.

Embodiment 2 In this embodiment, an example of an image display device using a surface conduction electron-emitting device will be described. Regarding the image display device, a method of manufacturing the image display device of the present invention will be described with reference to FIGS.

(Preparation of Rear Plate) (R-1) The blue plate glass was washed, and the lower wiring 23 was formed by screen printing on the rear plate on which a silicon oxide film was formed by a sputtering method. Next, the lower wiring 23 and the upper wiring 24
An interlayer insulating film was formed between them. Further, the upper wiring 24 was formed. Next, device electrodes 32 and 33 connected to the lower wiring 23 and the upper wiring 24 were formed. (R-2) Next, a conductive thin film 34 made of PdO was formed by a sputtering method and then patterned to obtain a desired form. (R-3) Frit glass for fixing the support frame was formed at a desired position by printing.

Through the above steps, a rear plate was formed on which a surface conduction electron-emitting device having a simple matrix wiring, an adhesive for a support frame, and the like were formed.

(Preparation of Face Plate) (F-1) A phosphor and a black conductor were formed on a blue plate glass substrate by a printing method. A smoothness treatment was performed on the inner surface of the fluorescent film, and thereafter, Al was deposited using a vacuum deposition method or the like to form a metal back. (F-2) Frit glass for fixing the support frame was formed at a desired position by a printing method.

Through the above steps, a phosphor in which the phosphors of the three primary colors are arranged in stripes, an adhesive for a support frame, and the like were formed on the face plate.

(Preparation of Airtight Container by Sealing Rear Plate and Face Plate) (FR-1) The rear plate is held on a hot plate on an X, Y, and θ adjustment stage, and sealed while aligning the face plate. The temperature of the rear plate and the face plate was raised to the deposition temperature. Although the sealing temperature is determined by the frit glass, the sealing temperature was 410 ° C. in this example. At the stage when the temperature is raised to the sealing temperature,
The support frame is brought into contact with the adjustment plate of X, Y, and θ while adjusting the position of the rear plate and the face plate, and is held for 10 minutes while being pressurized. When the temperature was lowered by 100 ° C., the alignment was stopped, the stage was set free, and the temperature was lowered to room temperature.

(Preparation of Electron Emitting Element by Vacuum Process) (S-1) Airtight container 100 prepared as described above
The exhaust pipes 11 and 12 on the face plate are connected to a vacuum exhaust device, and the inside of the airtight container 100 is exhausted to a vacuum. (S-2) When the pressure in the airtight container 100 becomes 0.1 Pa or less, the terminals Dox1 to Doxm and Doy1 outside the container.
To Doyn, a voltage was applied to the electron-emitting device, and a forming process was performed on the conductive thin film 34. (S-3) Subsequently, the pressure in the airtight container is 1 × 10 ⁻³ P
a, acetone is introduced as an activating gas through the exhaust pipe 11 into the airtight container at a pressure of 1 Pa.
A voltage was applied to the electron-emitting device through ox1 to Doxm and Doy1 to Doyn to perform an activation process.

(Degassing Step in Airtight Container) FIG. 1 shows a flowchart of the degassing step in the airtight container. (D-1) After the activation gas was sufficiently exhausted, a current was applied to the current introduction terminals 2 and 3 of the non-evaporable getter 1 to degas and activate the non-evaporable getter 1. The activation temperature of the non-evaporable getter 1 is determined by the non-evaporable getter 1. In this embodiment, the heating treatment is performed at 750 ° C. for 15 minutes. (D-2) Next, the airtight container was subjected to a baking degassing treatment. The baking temperature was 300 ° C. The heating rate was 2 ° C. per minute. (D-3) The temperature of the airtight container was kept at 300 ° C. for 10 hours, and baking was performed. (D-4) The airtight container was cooled at a rate of 2 ° C. per minute and cooled to room temperature. (D-5) A current was again applied to the current introduction terminals 2 and 3 of the non-evaporable getter to activate the non-evaporable getter. The activation temperature of the non-evaporable getter is 75 in this embodiment.
An electric heating treatment was performed at 0 ° C. for 15 minutes. (D-6) The evaporable getter is heated by induction heating, and B
a was evaporated and activated. (D-7) Remove the airtight container heating device and remove the exhaust pipe 11
And 12 were heated and melted to seal.

The change over time in the electron emission characteristics in the image display device prepared as described above was measured. FIG. 7 shows the result. A pulse waveform of a voltage of 15 V was applied between the electron-emitting devices, and a high voltage of Va = 5 kV was applied to the face plate. At this time, the current flowing through the face plate is defined as Ie. Here, Ie ₀ is an initial emission current. The value normalized by the current value immediately after voltage application is plotted.

(Comparative Example 2) (Degassing Step in Airtight Container) FIG. 5 is a flowchart of the degassing step in the airtight container. (D-1) The baking degassing process of the airtight container was performed. The baking temperature was 300 ° C. The heating rate was 2 ° C. per minute. (D-2) The temperature of the airtight container was kept at 300 ° C. for 10 hours, and baking was performed. (D-3) The airtight container was cooled at a rate of 2 ° C. per minute and cooled to room temperature. (D-4) heating the evaporable getter by induction heating,
a was evaporated and activated. (D-5) Remove the airtight container heating device, and remove the exhaust pipe 11
And 12 were heated and melted to seal.

The change over time in the electron emission characteristics in the image display device prepared as described above was measured. FIG. 7 shows the result.

From FIG. 7, it can be seen that the change rate of the emission current Ie / Ie ₀ which determines the luminance of the phosphor is more stable in the image display device manufactured in this embodiment than in the comparative example. .

(Embodiment 3) In the third embodiment of the present invention, a miniature gauge is provided at the end of the exhaust pipe 11 in order to evaluate the pressure in the panel in the same manner as in Embodiment 1 except for the degassing step in the airtight container. An image forming apparatus equipped with a (total pressure gauge) (not shown) was prepared.

FIG. 8 shows a flowchart of the degassing step in the airtight container. (D-1) After the activation gas was sufficiently exhausted, a current was passed through the current introducing terminals 2 and 3 of the non-evaporable getter 1 to degas and activate the non-evaporable getter. The activation temperature of the non-evaporable getter is determined by the non-evaporable getter. In this embodiment, the heating treatment is performed at 750 ° C. for 15 minutes. (D-2) Next, the airtight container was subjected to a baking degassing treatment. The baking temperature was 300 ° C. The heating rate was 2 ° C. per minute. (D-3) The temperature of the airtight container was kept at 300 ° C. for 10 hours, and baking was performed. (D-4) The airtight container was cooled at a rate of 2 ° C. per minute and cooled to room temperature. (D-5) The power introduction terminal 2 of the non-evaporable getter 1 again
An electric current was passed through and 3 to activate the non-evaporable getter. The activation temperature of the non-evaporable getter is 75 in this embodiment.
An electric heating treatment was performed at 0 ° C. for 15 minutes. (D-6) The evaporable getter is heated by induction heating, and B
a was evaporated and activated. (D-7) Remove the airtight container heating device and remove the exhaust pipe 11
Was melted by heating to seal. (D-8) A current was applied to the current introduction terminals 2 and 3 of the non-evaporable getter 1 again to activate the non-evaporable getter. The activation temperature of the non-evaporable getter is 7 in this embodiment.
An electric heating treatment was performed at 50 ° C. for 15 minutes.

The pressure in the airtight container 24 hours after the completion of the sealing is the first in the airtight container prepared in this embodiment.
15% lower than the pressure in the airtight container of the example. That is, the third activation of the non-evaporable getter further improves the degree of vacuum in the airtight container.

(Embodiment 4) In the first to third embodiments, the activation of the evaporable getter is performed before the airtight container is sealed, but if a leak occurs during sealing, Ba becomes barium oxide. It becomes white and unusable. In other words, it becomes impossible to reconnect the exhaust pipe for regeneration.

Therefore, the fourth embodiment of the present invention activates the evaporable getter after sealing. A miniature gauge (total pressure gauge) is provided at the end of the exhaust pipe 11 to evaluate with the pressure in the panel in the same manner as in Example 1 except for the degassing step in the airtight container.
An image forming apparatus to which (not shown) was attached was prepared.

FIG. 9 shows a flowchart of the degassing step in the airtight container. (D-1) After the activation gas is sufficiently exhausted, the evaporable getter is heated at 120 ° C. for 10 minutes by induction heating, followed by 200 to 50 minutes.
Heating was performed for 20 minutes at a temperature lower than the evaporation temperature of about 0 ° C. to degas the evaporable getter. (D-2) A current was applied to the current introduction terminals 2 and 3 of the non-evaporable getter to perform degassing and activation of the non-evaporable getter. The activation temperature of the non-evaporable getter is determined by the non-evaporable getter.
An electric heating process was performed for 15 minutes. (D-3) Next, the airtight container was subjected to a baking degassing treatment. The baking temperature was 300 ° C. The heating rate was 2 ° C. per minute. (D-4) The temperature of the airtight container was kept at 300 ° C. for 10 hours, and baking was performed. (D-5) The temperature of the airtight container was lowered at 2 ° C. per minute, and cooled to room temperature. (D-6) A current was again applied to the current introduction terminals 2 and 3 of the non-evaporable getter to activate the non-evaporable getter. The activation temperature of the non-evaporable getter is 75 in this embodiment.
An electric heating treatment was performed at 0 ° C. for 15 minutes. (D-7) The evaporable getter is heated by induction heating, and B
a was evaporated and activated. (D-8) Remove the airtight container heating device and remove the exhaust pipe 11
And 12 were heated and melted to seal. (D-9) The evaporable getter is heated by induction heating, and B
a was evaporated and activated.

The pressure inside the airtight container 24 hours after the completion of the sealing is the first in the airtight container prepared in this embodiment.
The pressure was equal to the pressure in the airtight container of the example. (D-
When the degassing process of the evaporable getter of 1) was not performed, the pressure in the hermetic container was about 35% higher than the pressure in the hermetic container created in this example.

(Embodiment 5) In the fifth embodiment of the present invention, an image display device using a surface conduction electron-emitting device was prepared in the same manner as in Embodiment 2 except for the step of degassing the inside of an airtight container.

FIG. 10 shows a flowchart of the degassing step in the airtight container. (D-1) After the activation gas is sufficiently exhausted, the evaporable getter is heated at 120 ° C. for 10 minutes by induction heating, followed by 200 to 50 minutes.
Heating was performed for 20 minutes at a temperature lower than the evaporation temperature of about 0 ° C. to degas the evaporable getter. (D-2) A current was applied to the current introduction terminals 2 and 3 of the non-evaporable getter to perform degassing and activation of the non-evaporable getter. The activation temperature of the non-evaporable getter is determined by the non-evaporable getter.
An electric heating process was performed for 15 minutes. (D-3) Next, baking and degassing of the airtight container was performed. The baking temperature was 300 ° C. The heating rate was 2 ° C. per minute. (D-4) The temperature of the airtight container was kept at 300 ° C. for 10 hours, and baking was performed. (D-5) The temperature of the airtight container was lowered at 2 ° C. per minute, and cooled to room temperature. (D-6) A current was again applied to the current introduction terminals 2 and 3 of the non-evaporable getter to activate the non-evaporable getter. The activation temperature of the non-evaporable getter is 75 in this embodiment.
An electric heating treatment was performed at 0 ° C. for 15 minutes. (D-7) The evaporable getter is heated by induction heating, and B
a was evaporated and activated. (D-8) Remove the airtight container heating device and remove the exhaust pipe 11
And 12 were heated and melted to seal. (D-9) The evaporable getter is heated by induction heating, and B
a was evaporated and activated. (D-10) A current was applied to the current introduction terminals 2 and 3 of the non-evaporable getter again to activate the non-evaporable getter. The activation temperature of the non-evaporable getter is 7 in this embodiment.
An electric heating treatment was performed at 50 ° C. for 15 minutes.

The change over time in the electron emission characteristics in the image display device prepared as described above was measured. The result is shown in FIG. From FIG. 11, Ie / Ie for determining the luminance of the phosphor is shown.
_It can be seen that ₀ is stable.

(Embodiment 6) In the sixth embodiment of the present invention, an image forming apparatus having the structure shown in FIG. 12 was produced.

In this embodiment, a plurality of field emission devices, which are cold cathode electron emission devices, are formed on the rear plate as electron emission devices, and spacers 116 are provided as atmospheric pressure support members for further weight reduction. A color image forming apparatus in which an effective display area was 10 inches diagonally and a length to width ratio was 3: 4 was prepared by installing a phosphor on the face plate.

In FIG. 12, reference numeral 111 denotes a rear plate,
112 is a face plate, 113 is a cathode, 114 is a gate electrode, and 115 is an insulating layer between the gate and the cathode.

FIG. 13 shows an image display apparatus of this embodiment, in which 112 is a face plate, 123 is a support frame,
11 is a rear plate, and 116 is a spacer. In addition,
The gap between the face plate 112 and the rear plate 111 is 1.5 mm. 131 is a non-evaporable getter, 134
Is an evaporable getter, and 128 and 129 are exhaust pipes.

Next, a method for manufacturing the image display device of the present invention will be described with reference to FIG.

(Preparation of Rear Plate) (R-1) The blue plate glass was washed, and a cathode (emitter) 113, a gate electrode 114, wiring, and the like shown in FIG. 12 were prepared by a known method. The cathode material was Mo. (R-2) Frit glass for fixing the support frame was formed at a desired position by printing.

Through the above steps, a rear plate on which a field emission type electron-emitting device having a simple matrix wiring, an adhesive for a support frame, and the like were formed.

(Preparation of Face Plate) (F-1) A phosphor and a black conductor were formed on a blue plate glass substrate by a printing method. A smoothing treatment was performed on the inner surface of the fluorescent film, and then Al was deposited by using a vacuum evaporation method or the like to form a metal back. (F-2) Frit glass for fixing the support frame was formed at a desired position by a printing method.

Through the above steps, a phosphor in which the phosphors of the three primary colors are arranged in stripes, an adhesive for a support frame, and the like were formed on the face plate.

(Preparation of Airtight Container by Sealing Rear Plate and Face Plate) (FR-1) The rear plate is held on a hot plate on an X, Y, and θ adjustment stage, and sealing is performed while aligning the face plate. Raise the temperature of the rear plate and face plate to the arrival temperature. Although the sealing temperature is determined by the frit glass, the sealing temperature was 460 ° C. in this example. At the stage when the temperature is raised to the sealing temperature,
The support frame is brought into contact with the adjustment plate of X, Y, and θ while adjusting the position of the rear plate and the face plate, and is held for 10 minutes while being pressurized. When the temperature was lowered by 100 ° C., the alignment was stopped, the stage was set free, and the temperature was lowered to room temperature.

(Vacuum Process) (S-1) A total pressure gauge is installed in the exhaust pipe 129 on the face plate of the airtight container prepared as described above.
The exhaust pipe 128 was connected to a vacuum exhaust device, and the inside of the airtight container was evacuated to a vacuum.

(Degassing Step in Airtight Container) FIG. 14 is a flowchart of the degassing step in the airtight container. (D-1) After the activation gas has been sufficiently exhausted, the evaporable getter 134 is heated by induction heating at 120 ° C. for 10 minutes, and then at a temperature of 200 to 500 ° C. or lower at an evaporating temperature of 20 minutes or less. Was degassed. (D-2) Lead-in terminal 2 for energization of the non-evaporable getter 131
An electric current was applied to and 3 to perform degassing and activation of the non-evaporable getter 131. The activation temperature of the non-evaporable getter is determined by the non-evaporable getter. In this embodiment, the heating treatment is performed at 750 ° C. for 15 minutes. (D-3) Next, the airtight container was subjected to a baking degassing treatment. The baking temperature was 350 ° C. The heating rate was 2 ° C. per minute. (D-4) The temperature of the airtight container was maintained at 350 ° C. for 10 hours, and baking was performed. (D-5) The temperature of the airtight container was lowered at 2 ° C. per minute, and cooled to room temperature. (D-6) A current was again applied to the current introduction terminals 2 and 3 of the non-evaporable getter to activate the non-evaporable getter. The activation temperature of the non-evaporable getter is 75 in this embodiment.
An electric heating treatment was performed at 0 ° C. for 15 minutes. (D-7) The evaporable getter is heated by induction heating, and B
a was evaporated and activated. (D-8) Remove the airtight container heating device and remove the exhaust pipe 12
8 was heated and melted, and sealing was performed. (D-9) Lead-in terminal 2 for energization of non-evaporable getter again
An electric current was passed through and 3 to activate the non-evaporable getter. The activation temperature of the non-evaporable getter is 75 in this embodiment.
An electric heating treatment was performed at 0 ° C. for 15 minutes.

The pressure in the image display device prepared as described above was measured after the sealing step. The result is shown in FIG. As a comparative example, FIG. 15 shows the measurement results of the pressure in the airtight container when the degassing step in the airtight container was performed according to the following procedure.

(Comparative Example 6) (Degassing Step in Hermetic Container) FIG. 16 is a flowchart of the degassing step in the hermetic container when only the non-evaporable getter is used. (D-1) A current was applied to the current introduction terminals 2 and 3 of the non-evaporable getter to perform degassing and activation of the non-evaporable getter 131. The activation temperature of the non-evaporable getter is determined by the non-evaporable getter.
An electric heating treatment was performed at 0 ° C. for 15 minutes. (D-2) Next, the airtight container was subjected to a baking degassing treatment. The baking temperature was 350 ° C. The heating rate was 2 ° C. per minute. (D-3) The temperature of the airtight container was maintained at 350 ° C. for 10 hours, and baking was performed. (D-4) The airtight container was cooled at a rate of 2 ° C. per minute and cooled to room temperature. (D-5) A current was again applied to the current introduction terminals 2 and 3 of the non-evaporable getter to activate the non-evaporable getter. The activation temperature of the non-evaporable getter was 750 ° C., and the heating treatment was performed for 15 minutes. (D-6) Remove the airtight container heating device and remove the exhaust pipe 12
8 was heated and melted, and sealing was performed. (D-7) Lead-in terminal 2 for energization of non-evaporable getter again
An electric current was passed through and 3 to activate the non-evaporable getter. The activation temperature of the non-evaporable getter was 750 ° C., and the heating treatment was performed for 15 minutes.

FIG. 15 shows that the degree of vacuum of the hermetic container of this embodiment is low from the initial state and is maintained for a long time in a stable and low vacuum state. In the comparative example, Ie / Ie ₀ sharply decreases from a certain time. This is considered to be because the released gas rate in the hermetic container of the comparative example was higher than that of the present example, and the life of the non-evaporable getter was extended.

[0097]

The stability of the device using the electron-emitting device is affected by the vacuum atmosphere in the airtight container.
Therefore, it is necessary to minimize the amount of gases such as water and oxygen, which are gas species that hinder the stability of the element.

In the present invention, since the non-evaporable getter is activated a plurality of times and the exhaust characteristics can be maintained at a high temperature,
By activating the non-evaporable getter before baking at a high temperature after evacuation and activating the non-evaporable getter again after baking, the pumping speed can be greatly recovered, so that the deterioration is quicker. The gas can be removed.

Therefore, according to the present invention, the non-evaporable getter is activated a plurality of times, the non-evaporable getter is activated, and the non-evaporable getter is activated again after the activation of the evaporable getter. By activating the getter, the electron emission characteristics can be operated stably for a long time, and an image forming apparatus having a long life can be provided.

[Brief description of the drawings]

FIG. 1 is a flowchart of a process according to a first embodiment.

FIG. 2 is a schematic view of an image display device using a surface conduction electron-emitting device.

FIG. 3 is a schematic view showing a configuration of a surface conduction electron-emitting device.

FIG. 4 is a graph showing temperature-dependent adsorption characteristics of the non-evaporable getter of the present embodiment.

FIG. 5 is a flowchart of a process of a comparative example.

FIG. 6 is a flowchart of a process according to a second embodiment.

FIG. 7 is a diagram showing a change over time in electron emission characteristics in Example 2 and Comparative Example.

FIG. 8 is a flowchart of a process according to a third embodiment.

FIG. 9 is a flowchart of a process according to a fourth embodiment.

FIG. 10 is a flowchart of a process according to a fifth embodiment.

FIG. 11 is a diagram showing a change over time in electron emission characteristics in Example 5 and Comparative Example.

FIG. 12 is a schematic view showing a configuration of a field emission device.

FIG. 13 is a schematic diagram showing a configuration of an image display device using a field emission device.

FIG. 14 is a flowchart of a process according to the sixth embodiment.

FIG. 15 is a diagram showing changes over time in electron emission characteristics when using the field emission type electron-emitting devices manufactured in Example 6 and the conventional example.

FIG. 16 is a flowchart of a process of a comparative example.

[Explanation of symbols]

 1, 131 Non-evaporable getter 2, 3 Current introduction terminal 4, 134 Evaporable getter 22 Surface conduction electron-emitting device 23 Row direction wiring (lower wiring) 24 Column direction wiring (upper wiring) 25, 31, 111, 125 Rear Plate 26, 123 Support frame 27, 112, 121 Face plate 32, 33 Device electrode 34 Conductive thin film 35 Electron emission unit 113 Cathode 114 Gate electrode 115 Insulating layer 116, 127 Spacer

Claims (10)

[Claims] 1. A method for manufacturing an image forming apparatus including an electron-emitting device, an image forming member, a non-evaporable getter, and an airtight container having an evaporable getter, wherein the non-evaporable getter is activated a plurality of times. Activating the evaporable getter. A method for manufacturing an image forming apparatus, comprising: 2. The method for manufacturing an image forming apparatus according to claim 1, further comprising a step of activating a non-evaporable getter before and after the step of baking the airtight container. Manufacturing method. 3. The method for manufacturing an image forming apparatus according to claim 1, further comprising: activating a non-evaporable getter before sealing the hermetic container; and non-evaporating again after sealing the hermetic container. Activating the mold getter. 4. The method for manufacturing an image forming apparatus according to claim 1, further comprising a step of activating the non-evaporable getter again after the step of activating the evaporable getter. Of manufacturing an image forming apparatus. 5. The method of manufacturing an image forming apparatus according to claim 1, further comprising a step of degassing the evaporable getter before the step of first activating the non-evaporable getter. Of manufacturing an image forming apparatus. 6. A method for manufacturing an image forming apparatus including an airtight container having an electron-emitting device, an image forming member, a non-evaporable getter, and an evaporable getter, wherein the air is exhausted by an exhaust device connected to the airtight container. A step of degassing the evaporable getter; a step of activating the non-evaporable getter; a step of baking the airtight container at a high temperature; and a step of reactivating the non-evaporable getter. A method for manufacturing an image forming apparatus, comprising: activating the evaporable getter; sealing the airtight container; and activating the non-evaporable getter again. 7. The image forming apparatus according to claim 6, further comprising a step of sealing the airtight container, a step of activating the evaporable getter, and a step of activating the non-evaporable getter. A method for manufacturing an image forming apparatus, comprising: 8. The method for manufacturing an image forming apparatus according to claim 1, wherein said electron-emitting device is:
A method of manufacturing an image forming apparatus, wherein the method is a cold cathode type electron-emitting device. 9. The method of manufacturing an image forming apparatus according to claim 1, wherein said electron-emitting device is:
A method for manufacturing an image forming apparatus, wherein the method is a field emission type electron emission element. 10. The method for manufacturing an image forming apparatus according to claim 1, wherein said electron-emitting device is a surface conduction electron-emitting device. Method.