JPH07302543A - Image formation device and its manufacture - Google Patents

Abstract

PURPOSE:To perform proper bonding over an entire container at its required minimum temperature if there is a distribution of the heating temperature during bonding. CONSTITUTION:A first frit glass 7a is applied to a part of a support frame 4 coming into contact with a front surface plate 2 and a rear surface plate 3, and a second frit glass 7b is applied to a part of a spacer 1 coming into contact with the front surface plate 2 and the rear surface plate 3. The front frit glass 7a and the second frit glass 7b are different from each other in their softening temperatures, the temperature of the outer circumferential part is higher than the internal temperature when heating is performed for bonding, therefore, the first frit glass 7a with its high softening temperature is applied to the outer circumferential part and the second frit glass 7b with its low softening temperature is applied to the inside.

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 a thin image forming apparatus which forms an image by applying an electron source, and an image forming apparatus.

[0002]

2. Description of the Related Art Conventionally, two types of electron emitters, a thermoelectron source and a cold cathode electron source, are known. Among them, the cold cathode electron source includes a field emission type (hereinafter abbreviated as “FE type”), a metal / insulating layer / metal type (hereinafter abbreviated as “MIM type”), a surface conduction type electron emitting device, and the like.

As an example of the FE type, WPDyke & WWDol
an, "Field emission", Advance in Electron Physics, 8,
89 (1956) and CASpindt, "Physical properties of thin-
film field emission cathodes with molybdenum cone
s ", J. Appl. Phys., 47, 5248 (1976) and the like.

As an example of the MIM type, CAMead, "The tu
nnel-emission amplifier ", J.Appl.Phys., 32,646 (1961)
Etc. are known.

Examples of surface conduction electron-emitting devices include E.
I. Elinson, Radio Eng. Electron Phys., 10, 1290 (1965).

The surface conduction electron-emitting device utilizes a phenomenon in which electron emission occurs when a current is passed through a thin film of a small area formed on a substrate in parallel with the film surface.

As the surface conduction electron-emitting device, one using the SnO ₂ thin film by Erinson et al.
By thin film [G.Dittmer: "Thin Solid Films", 9,31
7, (1972)], In ₂ O ₃ / SnO ₂ thin film [M.Ha
rtwell and CGFonstad: "IEEE Trans. ED Conf.", 519,
(1975)], a carbon thin film [Hiraki Araki et al .: "Vacuum", Vol. 26, No. 1, p. 22 (1983)] and the like.

A conventional image forming apparatus for forming an image by applying the above-mentioned electron-emitting device will be described with reference to FIGS. 6 and 7.

FIG. 6 is an exploded perspective view for explaining the structure of a conventional image forming apparatus, and FIG. 7 is a vertical sectional view of the image forming apparatus shown in FIG.

An image forming apparatus generally has a rear plate 103 having an electron-emitting device group mounted thereon, as shown in FIGS. 6 and 7.
And a front plate 102, which is arranged opposite to the rear plate 103 and has an image forming member on which an image is formed by irradiation of an electron beam from an electron-emitting device group, the front plate 102 and the rear plate 103.
And a supporting frame 1 for supporting the peripheral edges of the front plate 102 and the rear plate 103 so as to surround the electron-emitting device group.
04, and the joint portion of the front plate 102, the rear plate 103, and the support frame 104 is fixed by frit glass.

Further, the inside of the image forming apparatus is 10 ⁻⁶ To
Since the electron-emitting device is operated in a vacuum of about rr or higher, it is necessary to have a structure that can withstand the atmospheric pressure at this time.

In particular, in a flat image forming apparatus using a large-area back plate and front plate, when the atmospheric pressure applied perpendicularly to the surfaces of the front plate and the back plate is to be supported, each plate is thickened. Therefore, the feasibility becomes poor in terms of weight and cost. For this reason, the spacer 101 is arranged inside the support frame 104 between the front plate 102 and the rear plate 103 as a pillar to form an atmospheric pressure resistant structure and reduce the weight.

The spacer 101 is fixed by using frit glass like other joints. Further, it also has a function of accurately maintaining the distance between the electron-emitting device group formed on the back plate 103 and the image forming member of the front plate 102 at the position opposite to the electron-emitting device group.

[0014]

In the conventional example shown in FIGS. 6 and 7, frit glass having the same softening temperature is applied to a spacer and a support frame, or a front plate and a back plate, and these are bonded to each other. By heating above, the image forming apparatus has an airtight structure.

At the time of such joining, it is desirable to heat the entire container uniformly, but in reality, as the front plate and the back plate become larger, it becomes difficult to heat the container uniformly, and the temperature distribution at the time of heating is increased. Unevenness may occur. Therefore, when the joining is performed, the joining portion having the lowest temperature is heated so as to reach the softening temperature of the frit glass, so that the other joining portions are heated to the softening temperature of the frit glass or higher.

By the way, regarding the heating temperature at the time of joining,
The lower temperature is preferable in consideration of the influence on the element, the influence on the substrate and the frame. However, the conventional method as described above is not preferable because the portions other than the joint portion having the lowest temperature are heated more than necessary.

Therefore, from the viewpoint of simply lowering the heating temperature, it is conceivable to use a frit glass having a softening temperature lower than that of the conventionally used frit glass, but the softening temperature lower than that of the conventional one. Regarding frit glass having a temperature, crystallization tends to occur on the higher temperature side than the softening temperature, and if crystallization occurs, the fluidity of the frit glass at the time of bonding may be poor or the physical properties may change. However, there is a fact that the range from the softening temperature, which is the temperature range that can be actually used, to the temperature at which crystallization starts is narrow because it leads to poor bonding.

For this reason, since the temperature distribution at the time of joining is large, the frit glass is crystallized at the joining portion having a high temperature when the joining portion having a low temperature is set to the softening temperature.
Good joining cannot be performed, and conversely, if the high temperature joining portion is set to the softening temperature, the low temperature joining portion does not reach the softening temperature, which means that good joining cannot be performed, In any case, good joining cannot be realized in the entire container.

In view of the above-mentioned conventional state of the art, the present invention manufactures an image forming apparatus capable of performing good joining over the entire container at a necessary minimum temperature when the heating temperature at the time of joining has a distribution. An object is to provide a method and an image forming apparatus.

[0020]

The present invention for achieving the above object includes a back plate having a plurality of electron-emitting devices mounted thereon,
A front plate, which is arranged to face the back plate and has an image forming member on which an image is formed by irradiation of an electron beam emitted from the electron-emitting device; and between the back plate and the front plate, An airtight structure including at least a support frame that supports the peripheral edges of the back plate and the front plate, and a spacer that is arranged between the front plate and the back plate, which are bonded to each other using frit glass and then heated. In the method of manufacturing an image forming apparatus, a plurality of frit glasses having different softening temperatures are prepared, and the front plate, the rear plate, the support frame, and the variation in the reached temperature at the time of heating at each joining portion between the spacers. Correspondingly, frit glass with a high softening temperature is applied to the joints where the temperature is relatively high, and low softening temperature is applied to the joints where the temperature is relatively low. Characterized by applying a frit glass.

In this method of manufacturing an image forming apparatus, a reinforcing plate is provided on the back plate, and a softening temperature of the back plate or the reinforcing plate is adjusted according to the temperature reached at the time of heating at the joint between the back plate and the back plate. A plurality of different frit glasses may be applied and fixed.

At this time, it is preferable that the reinforcing plate has the same coefficient of thermal expansion as the back plate.

An image forming apparatus manufactured by such a manufacturing method also belongs to the present invention.

The image forming apparatus is characterized in that the inside of the apparatus formed by joining is in a vacuum, and the electron-emitting device is a surface conduction electron-emitting device.

[0025]

According to the present invention as described above, an image is formed by irradiating a back plate having a plurality of electron-emitting devices mounted thereon and an electron beam emitted from the electron-emitting devices which is arranged so as to face the back plate. A front plate on which the image forming member is mounted, a support frame between the back plate and the front plate for supporting the back plate and the peripheral edge of the front plate, and a spacer arranged between the front plate and the back plate. When bonding to each other using frit glass, prepare a plurality of frit glasses having different softening temperatures, the front plate, the back surface,
Corresponding to the variation in the temperature reached during heating at each joint between the support frame and the spacer, frit glass having a high softening temperature is applied to the joint where the temperature becomes relatively high, so that the temperature becomes relatively low. The frit glass having a low softening temperature is applied to the joining portion.

As a result, even if there is a difference in the heating temperature distribution at the time of joining, good joining can be achieved over the entire container at the minimum necessary temperature, and the influence of heat on the electron-emitting device and each component can be suppressed. It becomes possible.

[0027]

Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) FIG. 1 is a longitudinal sectional view showing a first embodiment of an image forming apparatus, which is suitable for carrying out the method of manufacturing an image forming apparatus according to the present invention, and FIG. FIG. 2 is a plan view showing a part of the image forming apparatus shown in FIG.

As shown in FIGS. 1 and 2, the image forming apparatus of this embodiment has a back plate 3 on which an electron-emitting device group 6 is mounted.
A front plate 2, which is arranged so as to face the rear plate 3 and has an image forming member 5 on which an image is formed by irradiation of electron beams emitted from the electron-emitting device group 6, the rear plate 3 and the front plate. 2 and at least a support frame 4 for supporting the peripheral edges of the back plate 3 and the front plate 2, and a spacer 1 arranged between the front plate 2 and the back plate 3 as an atmospheric pressure supporting member or a space setting member. Then, these are airtightly joined using frit glass.

In particular, the first frit glass 7a is applied to the portion of the support frame 4 in contact with the front plate 2 and the rear plate 3, and the portion of the spacer 1 in contact with the front plate 2 and the rear plate 3 is The second frit glass 7b is applied. The first frit glass 7a and the second frit glass 7b have different softening temperatures, and in the case of the container structure shown in FIGS. 1 and 2, the outer peripheral portion is higher than the inner temperature during heating for joining. Since it becomes higher, the first frit glass 7a having a higher softening temperature is applied to the outer peripheral portion, and the second frit glass 7b having a lower softening temperature is applied to the inside.

Next, a method of manufacturing the image forming apparatus in this embodiment will be described.

In this embodiment, the spacer 1 was made by etching photosensitive glass into a thin plate shape, and the front plate 2, the back plate 3 and the support frame 4 were made by cutting soda-lime glass.

A plurality of electron-emitting devices were formed on the back plate 3.

As the front plate 2, a glass substrate coated with a phosphor as an image forming member is used, as the first frit glass 7a, a softening temperature of 410 ° C. is used, and as the second frit glass 7b. Has a softening temperature of 38
The thing of 0 degreeC was used.

Next, the above-mentioned two kinds of frit glasses 7a and 7b having different softening temperatures are applied to the joint portions shown in FIGS. 1 and 2, and the back plate 3, the front plate 2, the support frame 4,
The spacer 1 was assembled, fixed using a jig, and baked in a furnace. At the time of firing, the joint between the front frame 2 and the rear plate 3 of the support frame 4 is kept at 410 ° C. or higher for about 10 minutes, and the joint between the spacer 1 and the front plate 2 and the rear plate 3 is about 10 minutes. The time kept at 380 ° C. or higher was about 10 minutes, and good bonding could be performed under these conditions.

Finally, a vacuum is evacuated by an exhaust pipe (not shown) provided in the support frame 4 or the like in order to make the inside of the container assembled in the above process a vacuum state, and then the exhaust pipe is sealed. , And an image forming apparatus.

In this embodiment, as shown in FIGS. 1 and 2, the frit glass has a portion of the support frame 4 which is in contact with the front plate 2 and the rear plate 3 and the spacer 1 which is the front plate 2 and the rear plate 3. It is painted separately to the part that touches. In the case of the container structure shown in these figures, when heating for joining, the temperature of the outer peripheral part of the container becomes higher and the temperature of the inner part becomes lower, so a frit with a high softening temperature in the outer part and a softening temperature in the inside Uses a low frit. However, the temperature distribution during heating when actually joining is affected by the heating method, and when a joining jig is used, it is also greatly affected by the jig material and shape. It is preferable to use a plurality of frit glasses having different softening temperatures according to the above temperature. As a selection method at this time, it is considered that the temperature of each portion during heating is measured in advance by using a thermocouple or the like, and the measurement result is dealt with.

(Second Embodiment) FIG. 3 is a vertical sectional view showing a second embodiment of the image forming apparatus, which is suitable for carrying out the method of manufacturing the image forming apparatus of the present invention. FIG. FIG. 4 is a plan view showing a part of the image forming apparatus shown in FIG.

Generally, as the vacuum container becomes larger,
The number of spacers, which are the atmospheric pressure resistant supporting members of the front plate and the rear plate, is also increased. However, the increase in the number of spacers leads to an increase in the surface area in the vacuum container, which is not preferable because the exhaust efficiency is deteriorated.

Therefore, the image forming apparatus of the present embodiment has the configuration shown in FIG.
As shown in FIG. 4 and FIG. 4, by fixing the reinforcing plate 28 to the back plate 23, the number of the spacers 1 is reduced as much as possible. Further, the reinforcing plate 28 is preferably the same as the thermal expansion coefficient of the back plate 23 because peeling may occur at the joint surface between the reinforcing plate 28 and the back plate 23 in consideration of the heating temperature during firing.

In this embodiment, the spacer 21, the support frame 24, the back plate 23, and the front plate 22 were manufactured by the same method as in the first embodiment. The reinforcing plate 28 was produced by cutting soda-lime glass.

Next, as three types of frit glass having different softening temperatures, a first frit glass 27a (softening temperature 410 ° C.) and a second frit glass 27b (softening temperature 3
80 ° C., third frit glass 27c (softening temperature 35
0 ° C.) is applied to the joint portions shown in FIGS. 3 and 4, and the back plate 23, the front plate 22, the support frame 24, the spacer 2 are applied.
1. The reinforcing plate 28 is combined and fixed using a jig,
Good bonding was achieved by firing in a furnace.

Finally, a vacuum is drawn by an exhaust pipe (not shown) provided in the support frame 24 or the like to make the inside of the container joined in the above step a vacuum, and then the exhaust pipe is sealed, The image forming apparatus is used.

In this embodiment, the frit glass is, as shown in FIGS. 3 and 4, a portion of the support frame 24 in contact with the front plate 22 and the rear plate 23 and a front plate of the spacer 21 on the support frame 24 side. 22 and a portion contacting the back plate 23 and a portion of the spacer 21 at the center of the interior that contacts the front plate 22 and the back plate 23 are separately painted. In the case of the container structure shown in these figures, the temperature distribution at the time of heating is higher in the outer peripheral part and becomes lower as it goes to the inner center, so a frit with a high softening temperature is used in the outer part and the inner center is used. As a result, the frit has a low softening temperature.
However, the temperature distribution during heating when actually joining is affected by the heating method, and when a joining jig is used, it is also greatly affected by the jig material and shape. It is preferable to use a plurality of frit glasses having different softening temperatures according to the above temperature. As a selection method at this time, it is considered that the temperature of each portion during heating is measured in advance by using a thermocouple or the like, and the measurement result is dealt with.

In the present invention described using each of the above-described embodiments, the shape, number and arrangement of spacers are not particularly limited. Such a spacer is used as an atmospheric pressure resistant support member for the front plate and the rear plate and / or a member for setting a distance between them. Further, frit glass having a melting point sufficiently lower than that of each member constituting the image forming apparatus is used.

[0046] The softening temperature in the present invention is the temperature at which the viscosity of the frit glass is equivalent to ^{10 7.65 dPa · s {poise}} , be joined by heating at above the softening temperature temperature (sintering temperature) it can.

In addition, the cold cathode electron source described in the description of the prior art can be used as the plurality of electron-emitting devices mounted on the back plate. A surface conduction electron-emitting device (SCE) will be taken as an example of the cold cathode electron source and its configuration will be briefly described. 5A and 5B show an example of a basic configuration of a surface conduction electron-emitting device, FIG. 5A is a plan view thereof, and FIG. 5B is a longitudinal sectional view thereof.

As shown in FIG. 5, the surface conduction electron-emitting device has an insulating substrate 11, and device electrodes 15 and 16 are arranged on the insulating substrate 11 at regular intervals L1. Each device electrode 15 on this insulating substrate 11,
A thin-film conductor 14 is formed between 16. The thin-film conductor 14 is formed with an electron-emitting portion 13 that emits electrons by heating the thin-film conductor 14 by energization and heating (JP-A-2-56822 and JP-A-4-28139).
(See the official gazette).

The electron emitting portion 13 is made of conductive fine particles having a particle size of about several tens of angstroms.
The thin film conductors 14 other than 3 are made of fine particle films.

The fine particle film described here is a film in which a plurality of fine particles are aggregated, and its fine structure is not only a state in which the fine particles are dispersed and arranged but also a state in which the fine particles are adjacent to each other or overlap each other (islands). (Including the shape).

In addition to this, the thin film conductor 14 may be a carbon thin film in which conductive fine particles are dispersed.

To give a specific example of the thin film conductor 14,
Pb, Ru, Ag, Ti, In, Cu, Cr, Fe, Z
n, Sn, Ta, W, Pb and other metals, PbO, SnO
Oxides such as ₂ , In ₂ O ₃ , PbO and Sb ₂ O ₃ , HfB
2, boride such as ZrB2, LaB6, CeB6, YB4, GdB4, TiC, ZrC, HfC, TaC, SiC, W
Carbides such as C, nitrides such as TiN, ZrN and HfN, semiconductors such as Si and Ge, carbon, AgMg, N
iCu and the like.

The thin film conductor 14 is formed by the vacuum evaporation method,
It is formed by a sputtering method, a chemical vapor deposition method, a dispersion coating method, a dipping method, a spinner method, or the like.

An example of the method of manufacturing the surface conduction electron-emitting device will be described. First, in FIG. 5, soda lime glass is used as the insulating substrate 11, and Ni is used on the insulating substrate 11 to form the device electrodes 15 and 16. Was formed. At this time,
Element electrode interval L1 is 3 μm, element electrode width W1 is 500 μm
m, and the thickness d of the device electrode was 1000Å.

Next, organopalladium (ccp-4230: manufactured by Okuno Chemical Industries Co., Ltd.) is placed at desired positions including on the device electrodes.
After applying the containing solution, heat treatment is performed at 300 ° C. for 10 minutes to obtain palladium oxide (PdO) fine particles (average particle diameter:
A thin film conductor 14 made of 70Å) was formed. At this time,
The width W2 of the thin film conductor 14 was 300 μm.

The present invention is not limited to such a surface conduction electron-emitting device (SCE), and an FE type, MIM type or the like as described in the description of the prior art may be used.

[0057]

As described above, the present invention provides a front plate,
When bonding the back plate, the support frame, and the spacer to each other, prepare a plurality of frit glasses having different softening temperatures, and the front plate, the back surface, the support frame, and the temperature reached at the time of heating at each bonding site between the spacers To cope with variations,
By applying frit glass with a high softening temperature to the joints that have a relatively high temperature and by applying frit glass with a low softening temperature to the joints that have a relatively low temperature, the heating temperature at the time of bonding can be improved. Even with the distribution, good bonding can be achieved throughout the container at the minimum required temperature. This facilitates the manufacture of the image forming apparatus and improves the yield.

By fixing the reinforcing plate to the back plate, the number of spacers can be reduced as much as possible, and the exhaust efficiency when the inside of the container is evacuated can be improved.

Since the reinforcing plate has the same coefficient of thermal expansion as that of the back plate, there is no risk of peeling at the joint surface between the reinforcing plate and the back plate during heating during bonding.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a first embodiment of an image forming apparatus, which is suitable for carrying out the method of manufacturing an image forming apparatus of the present invention.

FIG. 2 is a plan view of the image forming apparatus shown in FIG.

FIG. 3 is a vertical sectional view showing a second embodiment of the image forming apparatus, which is suitable for carrying out the method of manufacturing the image forming apparatus of the present invention.

FIG. 4 is a plan view in which a part of the image forming apparatus shown in FIG. 3 is cut away.

5A and 5B show an example of a basic configuration of a surface conduction electron-emitting device, in which FIG. 5A is a plan view thereof and FIG. 5B is a vertical sectional view thereof.

FIG. 6 is an exploded perspective view for explaining the configuration of a conventional image forming apparatus.

7 is a vertical cross-sectional view of the image forming apparatus shown in FIG.

[Explanation of symbols]

 1, 21 Spacer 2, 22 Front plate 3, 23 Rear plate 4, 24 Support frame 5, 25 Image forming member 6, 26 Electron emitting device group 7a, 27a First frit glass 7b, 27b Second frit glass 27c Frit glass of 3 28 Reinforcing plate 11 Insulating substrate 13 Electron emitting portion 14 Thin film conductor 15 and 16 Element electrode

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Tadashi Kaneko 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Tomokazu Ando 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Co., Ltd. (72) Inventor Naoto Nakamura 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Hideaki Mitsutake 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Yoshiyuki Nagata 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (6)

[Claims] 1. A back plate on which a plurality of electron-emitting devices are mounted, and an image forming member which is arranged so as to face the back plate and on which an image is formed by irradiation of an electron beam emitted from the electron-emitting devices. At least a mounted front plate, a support frame between the back plate and the front plate for supporting the back plate and the peripheral edges of the front plate, and a spacer arranged between the front plate and the back plate, In a method of manufacturing an image forming apparatus in which an airtight structure is formed by joining the above with each other using frit glass and then heating, preparing a plurality of frit glasses having different softening temperatures, the front plate, the back plate, and the support frame. Corresponding to the variation in the temperature reached during heating at each joint between the spacers, frit glass having a high softening temperature is used at the joint where the temperature is relatively high. And cloth, the joining portion to be relatively low temperature, characterized by applying a low frit glass softening temperature, method of manufacturing an image forming apparatus. 2. A reinforcing plate is applied to the back plate, and a plurality of frit glasses having different softening temperatures are applied to the back plate or the reinforcing plate in accordance with the temperature reached during heating at the joint between the reinforcing plate and the back plate. The method for manufacturing an image forming apparatus according to claim 1, wherein the method is followed by fixing. 3. The method of manufacturing an image forming apparatus according to claim 2, wherein the reinforcing plate has the same coefficient of thermal expansion as the back plate. 4. An image forming apparatus manufactured by the manufacturing method according to claim 1. 5. The image forming apparatus according to claim 4, wherein the inside of the apparatus formed by joining is evacuated. 6. The image forming apparatus according to claim 4, wherein the electron-emitting device is a surface conduction electron-emitting device.