JP3630784B2 - Manufacturing method of image forming apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method of manufacturing an image forming apparatus such as an image display device or a recording device.
[0002]
[Prior art]
Among the image forming apparatuses, the flat type image display apparatus includes a plasma display, an EL display apparatus, and a flat type display apparatus using an electron beam. In recent years, demands for large screens and high definition have increased. There is a growing need for self-luminous image forming apparatuses.
[0003]
As a flat type image forming apparatus using an electron beam, for example, a surface conduction electron-emitting device is used as an electron source for generating an electron beam in a vacuum panel sandwiched between a face plate and a back plate, and the electron beam is accelerated. A thin image forming apparatus for irradiating a phosphor to emit light and forming an image has been filed by the present applicant (see Japanese Patent Application Laid-Open No. 3-261024).
[0004]
FIG. 8 shows a cross section of a flat plate type image forming apparatus using such a surface conduction electron-emitting device. In FIG. 8, 1 is a substrate made of an insulating material such as blue plate glass, that is, a back plate, 3 is an element electrode placed at a fixed interval (about 2 μm), and 2 is formed by applying organic Pd. The electroconductive thin film 4 is an electron emission portion, and a voltage is applied between the element electrodes to conduct heating and form the electron emission portion 4, and electrons are emitted from the electron emission portion 4. Other examples of surface conduction electron-emitting devices include those using SnO ₂ films and those using Au thin films [G. Dittmer: Thin Solid Films, 9, 317 (1972)], using In ₂ O ₃ thin film [M. Hartwell and C.H. G. Fonstad: IEEE Trans. , ED Conf. 519 (1975)], and those using carbon thin films [Hisa Araki et al .: Vacuum, Vol. 26, No. 1, pp. 22 (1983)] have been reported.
[0005]
Further, in FIG. 8, 105 is an insulating layer formed on the back plate 1, 6 is a grid formed on the insulating layer 105, and is a modulation electrode having a hole through which an electron beam passes, and 10 is an Al thin film. A phosphor 8 covered with a metal back 9 is a face plate made of blue glass 7 placed on the inner surface of the panel, 12 is a low melting glass, and the face plate 10 and the back plate 1 are heated with the outer frame 11 sandwiched between them. Adhering and fixing to form a flat image forming apparatus.
[0006]
In the manufacture of such a flat type image forming apparatus, when the low melting point glass 12 is applied to the face plate 10, the frame 11, and the back plate 1 and fixed in an electric furnace, the position of the phosphor 8 and the electron emission portion After performing the above positioning, after fixing with a jig or the like, it is put in an electric furnace and heated to a temperature equal to or higher than the melting point of the low-melting glass to be bonded and fixed.
[0007]
Next, the air between the back plate 1 and the face plate 10 is evacuated to a pressure of 1 × 10 ⁻⁶ Torr or less by a vacuum pump such as a turbo molecular pump through an exhaust pipe (not shown). Next, a voltage is applied and an energization process is performed to form the electron emission portion 4. Further, after the entire image forming apparatus is baked and sufficiently degassed, a getter material (not shown) is blown off. Finally, the exhaust pipe (not shown) is sealed off.
[0008]
In the image forming apparatus manufactured as described above, the surface conduction electron-emitting device and the grid 6 are connected to a driving device, and the metal back 9 is connected to a high voltage power source. The inside of the image forming apparatus is maintained at a vacuum of 1 × 10 ⁻⁶ Torr or less, and when a driving pulse voltage is applied between the electrodes 3 by the driving device, electrons are emitted in the form of a beam, and the electron beam passes through the grid 6. Then, it is accelerated by a positive high voltage applied to the metal back 9 from a high voltage power source (not shown), and collides with the phosphor 8 to emit light. The electron beam can be controlled by a voltage applied to the grid 6 by a driving device (not shown), whereby the emission of the phosphor can be controlled and a desired image can be formed.
[0009]
[Problems to be solved by the invention]
However, in the manufacture of the image forming apparatus as described above, the conventional bonding and fixing method between the face plate and the back plate has the following problems.
[0010]
That is, when fixing the face plate, frame, and back plate, after aligning the position of the phosphor with the electron-emitting device, fixing it with a jig, etc., then placing it in an electric furnace or the like and firing and fixing To obtain a strong bond without vacuum leakage. However, as the temperature of the low melting point glass rises, the viscosity decreases and liquefies. Therefore, even if the face plate and the back plate are aligned in advance and fixed with a jig or the like, the low melting point glass Due to the lowering of the viscosity, the back plate and the face plate move to cause positional deviation, and the position of the phosphor and the position of the electron emitting portion are also shifted, making it difficult to produce with high accuracy. For this reason, there is a problem that the yield is poor and the cost is high.
[0011]
[Means for Solving the Problems]
Therefore, as a result of intensive studies to solve these problems in the method for manufacturing the flat-plate-type image forming apparatus, the present inventors have conducted an alignment process and a heating and fixing process in the same apparatus. It has been found that the above problems can be solved by carrying out in parallel, and the present invention has been completed. The present invention provides the following method for manufacturing a flat type image forming apparatus.
[0012]
That is, in the method for manufacturing a flat-plate-type image forming apparatus of the present invention, a face plate having a phosphor and a back plate having a source or an electrode for generating an energy beam for emitting the phosphor are arranged opposite to each other. In the manufacturing method of the flat plate type image forming apparatus in which both are bonded and fixed by heating , the positional displacement between the face plate and the back plate is shifted while the bonding agent for bonding the face plate and the back plate is softened. A method for manufacturing an image forming apparatus, comprising: detecting and aligning a face plate and a back plate based on the detection result .
[0014]
DETAILED DESCRIPTION OF THE INVENTION
In the present invention, as a generation source for generating an electron beam that emits a phosphor, it has at least one element row formed by arranging and connecting a plurality of surface conduction electron-emitting devices in parallel, An electron source having wiring for driving is preferably used. A thermoelectron source using a thermal cathode, a field emission type electron-emitting device [W. P. Dyke & W. W. Dolan, Field emission, Advances in Electron Physics, 8, 89 (1956) and C.I. A. Spindt, Physical properties of thin-film field emission catalyst with molecular denes, J. MoI. Appl. Phys. , 47, 5248 (1976), etc.], metal / insulating layer / metal-type electron-emitting device [C. A. Mead, The tunnel-emission amplifier, J. Am. Appl. Phys. , 32, 646 (1961), etc.] can also be used.
[0015]
Hereinafter, the present invention will be described in detail with reference to the drawings.
[0016]
FIG. 1 is a perspective view of an embodiment of an image display apparatus which is one of flat plate image forming apparatuses manufactured according to the present invention. In FIG. 1, 1 is a back plate, 3 is a device electrode, 4 is an electron emission portion, 5 is an electron passage hole, 6 is a grid, 10 is a face made of a transparent glass substrate 7, and having a phosphor 8 and a metal back 9. A plate, 11 is a frame, and 12 is a low-melting glass. In FIG. 1, the face plate 10 is cut so that the cross section and the back plate 1 side can be seen.
[0017]
The manufacturing method of the present invention is a method for fixing the back plate 1 and the face plate 10 of such a flat type image forming apparatus with a frame 11 and a low melting point glass 12 with high positional accuracy, respectively. A manufacturing apparatus as shown in FIG. In FIG. 2, 14 is an electric furnace, 15 is an alignment detection device, 16 is a control device, and 17 is an adjustment mechanism. Reference numeral 1 denotes a back plate, 10 denotes a face plate, and 11 denotes a frame. FIG. 5 differs from that shown in FIG. 2 in that the adjusting mechanism 17 is on the back plate 1 side. In the present invention, the adjusting mechanism may be on either side.
[0018]
In the present invention, the back plate 1 having the electron-emitting device on the inside, the phosphor 8 is applied to the inner surface, and the face plate 10 and the frame 11 are made to adhere to the surface of the phosphor having conductivity. An image forming apparatus in which low melting point glass is applied in advance and placed in an electric furnace 14 provided with a container capable of heating the whole, the back plate 1 and the face plate 10 are fixed with a jig or the like, and the temperature of the electric furnace is increased. Then, the alignment detection device 15 is used to align the alignment marks on the back plate 1 and the face plate 10 to perform alignment. When the temperature of the electric furnace rises, the viscosity of the low melting point glass decreases and liquefies, so that the face plate 10 and the back plate 1 move, and the positions are shifted. Then, the deviation is detected by the alignment detection device 15, receives a signal from the control device 16, and the face plate 10 or the back plate 1 is adjusted by the adjustment mechanism 17. In this way, the positional deviation is adjusted.
[0019]
FIG. 3 and FIG. 4 show one aspect of the positional deviation adjustment method. 3 and 4 are enlarged perspective views of the alignment portion. The face plate 10 has an alignment mark 20 (a cross is used in this embodiment), and the back plate 1 has an alignment mark 20 written thereon. By aligning these, alignment is performed, and when the alignment detection device 15 detects that they are shifted from each other as shown in FIG. 3, a signal from the control device 16 is received, and the adjustment mechanism 17 in FIG. Thus, the face plate 10 is adjusted.
[0020]
6 and 7 also show a similar adjustment method, which is an example corresponding to the aspect of adjusting the back plate 1 of the manufacturing apparatus shown in FIG.
[0021]
Here, the shape of the alignment mark used for alignment is not limited, and the back plate 1 can be formed simultaneously with the formation of the electron-emitting device. Similarly, the face plate 10 may be formed at the same time when the phosphor or the like is formed. Further, the detection of the shift is not limited to an optical one, and in short, any detection is possible as long as the shift can be detected in a heated furnace.
[0022]
In addition to using low melting point glass for sealing the face plate 10, the back plate 1 and the frame 11, the method is not limited as long as it can be bonded in a furnace, such as sealing with an adhesive.
[0023]
Then, it cools slowly, returns to room temperature, and takes out an image forming apparatus from an electric furnace.
[0024]
In FIGS. 2 and 5, a heater is illustrated as a heating means. However, the present invention is not particularly limited to this, and any method can be used as long as it can be heated at a desired temperature for a predetermined time. You may use anything.
[0025]
Thus, in a state where the positions of the face plate 10 and the back plate 1 are adjusted, the low-melting point glass is fixed, sealing is completed, and strong adhesion without leakage can be obtained. Since it is necessary to align each color phosphor of the face plate 10 and the electron-emitting device of the back plate 1 with high accuracy, the accuracy of the adjusting mechanism 17 is preferably ± 10 μm, and sealed with equal accuracy. To wear.
[0026]
FIG. 9 shows a basic configuration of the surface conduction electron-emitting device on the back plate side in FIG. FIG. 9A is a plan view, and FIG. 9B is a cross-sectional view. 9, the same reference numerals as those in FIG. 1 denote the same members, and 2 denotes a conductive thin film.
[0027]
As the back plate 1, for example, quartz glass, glass with reduced impurity content such as Na, blue plate glass, a laminated body in which SiO ₂ is laminated on the blue plate glass by a sputtering method, ceramics such as alumina, or the like is used.
[0028]
As a material of the element electrode 3, a general conductive material is used, for example, a metal or alloy such as Ni, Cr, Au, Mo, W, Pt, Ti, Al, Cu, Pd, and Pd, Ag, Au, RuO _2. , Pd—Ag or other metal or metal oxide and a printed conductor composed of glass or the like, a transparent conductor such as In ₂ O ₃ —SnO _2, or a semiconductor material such as polysilicon.
[0029]
The element electrode interval L, the element electrode length W1, the shape of the conductive film 2, and the like are appropriately designed according to the applied form and the like.
[0030]
The element electrode interval L is preferably several hundred to several hundred μm, and more preferably several μm to several tens μm depending on the voltage applied between the element electrodes.
[0031]
The element electrode length W1 is preferably several μm to several hundred μm in consideration of the resistance value of the electrode and electron emission characteristics, and the element electrode thickness d is several hundred to several μm.
[0032]
In the conductive film 2 including the electron emission portion 4 of the electron-emitting device, the electron emission portion 4 is made of conductive fine particles having a particle size of several tens of millimeters, and the conductive film 2 may be made of a conductive fine particle film. The fine particle film is a film in which a plurality of fine particles are aggregated, and the fine structure indicates not only a state where the fine particles are dispersed and arranged, but also a film in which the fine particles are adjacent to each other or overlap each other (including islands). . The film thickness is appropriately selected depending on the step coverage to the element electrode 3, the resistance value between the element electrodes, and the like, preferably several to several thousand, particularly preferably 10 to 200, and the resistance is 10 ^3. It is a sheet resistance value of -10 ⁷ Ω / mouth.
[0033]
Examples of the material constituting the conductive film 2 include metals such as Pd, Ru, Ag, Au, Ti, In, Cu, Cr, Fe, Zn, Sn, Ta, W, and Pb, PdO, SnO ₂ , Oxides such as In ₂ O ₃ , PbO, Sb ₂ O ₃ , borides such as HfB ₂ , ZrB ₂ , LaB ₆ , CeB ₆ , YB ₄ , GdB ₄ , TiC, ZrC, HfC, TaC, SiC, WC, etc. Carbides, nitrides such as TiN, ZrN, and HfN, semiconductors such as Si and Ge, carbon, AgMg, and NiCu.
[0034]
The electron emission portion 4 includes a crack, and the electron emission is performed from the vicinity of the crack.
[0035]
There are various methods for manufacturing such a surface conduction electron-emitting device, and an example thereof will be briefly described with reference to FIG.
[0036]
1) After sufficiently cleaning the back plate (substrate) 1, an element electrode material is deposited by vacuum deposition, sputtering, or the like, and then an element electrode 3 is formed on the surface of the substrate 1 by a photolithography technique ( FIG. 10 (a)).
[0037]
2) An organic metal solution is applied on the substrate 1 provided with the element electrode 3 and left to stand, thereby forming an organic metal thin film in communication between both element electrodes. The organometallic solution is a solution of an organic compound containing a metal as a constituent material of the conductive film 2 as a main element. Thereafter, the organic metal thin film is heated and baked to form a conductive film 2 patterned by lift-off, etching, or the like (FIG. 10B). Here, the application method of the organic metal solution has been described. However, the present invention is not limited to this. For example, the organic metal solution may be formed by vacuum evaporation, sputtering, chemical vapor deposition, dispersion coating, dipping, spinner, or the like. A film can also be formed.
[0038]
3) Thereafter, an energization process called forming is performed in an appropriate vacuum atmosphere. When electricity is supplied between the element electrodes 3 from a power source (not shown), the electron emission portion 4 having a changed structure is formed in the portion of the conductive film 2 (FIG. 10C). By this energization process, the conductive film 2 is locally broken, deformed or altered, and the site where the structure is changed is the electron emission portion 4.
[0039]
4) Preferably, the electron-emitting device fabricated in this way is driven to operate in a vacuum atmosphere higher than the degree of vacuum in the forming process, for example, about 10 ⁻⁶ Torr or less.
[0040]
Note that the steps after the forming step are usually performed after the back plate and the face plate are fixed and sealed.
[0041]
An electron source as an electron beam generating source preferably used in the present invention uses a plurality of such surface-conduction electron-emitting devices arranged and connected. As a method of this arrangement, a plurality of electron-emitting devices are arranged in parallel and both ends (both device electrodes) of each electron-emitting device are connected by wiring, and n on the m X-directional wirings. A simple matrix arrangement in which a Y-direction wiring of a book is installed via an interlayer insulating layer, and an X-direction wiring and a Y-direction wiring are connected to a pair of element electrodes of the electron-emitting device, respectively.
[0042]
A grid 6 is provided between the face plate 10 and the back plate 1 as shown in FIG. The grid 6 is an electrode that can modulate the electron beam emitted from the electron-emitting device. The grid 6 is formed by patterning a resist on the back plate 1 and performing etching. After performing Au wiring having a thickness of 1 μm, for example, an insulating material film is formed by a method such as sputtering. A metal such as Au, Al, Cu or the like is deposited thereon, and the electron passage hole 5 is formed by etching.
[0043]
【Example】
[Example 1]
In accordance with the process shown in FIG. 10, the image display apparatus shown in FIG. 1 was prepared using an electron-emitting device using a PdO film as an electron source.
[0044]
First, an Au element electrode 3 having a gap width of 2 μm, a gap length of 400 μm, and a thickness of 1000 mm was formed on the glass substrate 1 by a lift-off method [FIG. 10A].
[0045]
Next, an organic Pd solution [CCP4230O manufactured by Okuno Pharmaceutical Co., Ltd.] was applied and baked at 300 ° C. for 15 minutes. Next, the resist pattern is patterned and etched to cover the gap between the electrodes 3 and cover the gap between the electrodes 3. The conductive film 2 has a pattern length of 280 μm (corresponding to W2 in FIG. 9) and a width of 30 μm. [Fig. 10 (b)]. Through this process, 600 × 400 surface-conduction electron-emitting devices were arranged on the same glass substrate in a ladder shape as shown in FIG.
[0046]
Further, a 10 μm thick film of SiO ₂ as an insulating material is formed on the substrate (back plate) 1 by sputtering, and Au is vapor-deposited on the insulating film, and etching is performed. The grid 6 was formed integrally with the back plate 1.
[0047]
Further, the phosphor 8 was previously applied on another transparent glass substrate, the surface was smoothed, and Al was vacuum deposited to form a metal back (anode electrode) 9 to obtain a face plate 10.
[0048]
Next, low melting point glass 12 is applied in advance on the face plate 10, the frame 11 having a height of 5 mm, and the portion to be bonded to the back plate 1, and arranged as shown in FIG. Placed in furnace 14. The temperature of the electric furnace 14 is increased, heated at 430 ° C. for 1 hour, and the alignment detection device 15 is used to mark the alignment marks on the face plate 10 and the back plate 1 (using the crosses shown in FIGS. 3 and 4). Alignment was performed. In the apparatus of FIG. 2, as described above, the alignment, that is, the adjustment of the displacement is detected by the detection device 15, and the face plate 10 is adjusted by the adjustment mechanism 17 that receives the signal from the control device 16. , Alignment is performed.
[0049]
As described above, the low melting point glass 12 was fixed in a state where the positions of the face plate 10 and the back plate 1 were adjusted, sealing was completed, and strong adhesion with no vacuum leakage was obtained.
[0050]
The temperature of the electric furnace 14 was slowly cooled and taken out, and the inside of the image display device was evacuated to 10 ⁻⁶ Torr or less by a turbo molecular pump from the exhaust pipe. Thereafter, 5 V was applied between the electrodes 3 through the wiring, a current of about 20 mA was applied per element, an energization process was performed, and the electron emission portion 4 was formed.
[0051]
Subsequently, the image display device was heated to about 130 ° C. with a hot plate, evacuated from an exhaust pipe (not shown), and the inside of the image display device was evacuated to 10 ⁻⁶ Torr or less. After the getter material (not shown) installed in the vacuum container of the image display apparatus was blown, the exhaust pipe was heated with a gas burner and sealed.
[0052]
According to this embodiment, there is no need for alignment before entering the electric furnace, the electric furnace has an alignment function, alignment can be performed while the temperature is raised, and the alignment time is shortened. .
[0053]
[Example 2]
Using the manufacturing apparatus shown in FIG. 5, the image display apparatus shown in FIG. 1 was manufactured in exactly the same manner as in Example 1.
[0054]
First, a back plate 1 having electron-emitting devices, grids 6 and the like is prepared in the same manner as in Example 1, and then a face plate 10, a frame 11, and a back that have been pre-coated with a phosphor to have conductivity. The low melting point glass 12 is applied to the part of the plate 1 to be bonded, placed in the electric furnace 14 of the manufacturing apparatus shown in FIG. 5, the temperature of the electric furnace is increased, and the alignment detection apparatus 15 is heated at 430 ° C. for 1 hour. Using the alignment marks (the crosses shown in FIGS. 6 and 7) on the face plate 10 and the back plate 1, the alignment was performed. The adjustment of the positional deviation was performed by adjusting the back plate 1 by the adjusting mechanism 17.
[0055]
Thereafter, the inside of the image display device was evacuated in the same manner as in Example 1, energized, further evacuated, and the exhaust pipe was heated and sealed.
[0056]
【The invention's effect】
As described above, according to the present invention, when the back plate and the face plate are bonded and fixed, the step of aligning the face plate and the back plate, the face plate, the frame, and the back plate are heated and bonded. Since the fixing step is performed in parallel in the same apparatus, accurate sealing can be performed without failure. Therefore, it is possible to manufacture an image forming apparatus in which the positions of the phosphor and the electron-emitting device are in good agreement, and thus sharp in image quality, with a high yield, and the productivity can be improved and the manufacturing cost can be reduced.
[Brief description of the drawings]
FIG. 1 is a perspective view of an image display device showing an embodiment of an image forming apparatus manufactured according to the present invention.
FIG. 2 is a schematic view showing an aspect of an image forming apparatus manufacturing apparatus according to the present invention.
FIG. 3 is an enlarged view of an alignment mark portion showing adjustment of a face plate and a back plate.
FIG. 4 is an enlarged view of an alignment mark portion showing adjustment of a face plate and a back plate.
FIG. 5 is a schematic view showing an aspect of an image forming apparatus manufacturing apparatus according to the present invention.
FIG. 6 is an enlarged view of an alignment mark portion showing adjustment of a face plate and a back plate.
FIG. 7 is an enlarged view of an alignment mark portion showing adjustment of a face plate and a back plate.
FIG. 8 is a cross-sectional view showing an aspect of an image forming apparatus manufactured according to the present invention.
FIGS. 9A and 9B are a plan view and a cross-sectional view showing the basic configuration of the electron-emitting device of the electron source used in the present invention. FIGS. 10A and 10B are cross-sectional views showing the steps for producing the electron-emitting device.
[Explanation of symbols]
1 Back plate (insulating substrate)
2 Conductive film 3 Element electrode 4 Electron emission portion 5 Electron passage hole 6 Grid 7 Transparent substrate 8 Phosphor 9 Metal back 10 Face plate 11 Frame 12 Low melting point glass 14 Electric furnace 15 Alignment detection device 16 Control device 17 Adjustment mechanism 20 Alignment mark

Claims (3)

A face plate having a phosphor, to face the back plate having a source or electrodes for generating an energy beam to emit fluorescent body arranged, bonded by heating both, flat type image forming for fixing In the manufacturing method of the apparatus, while the bonding agent for bonding the face plate and the back plate is softened, a positional deviation between the face plate and the back plate is detected, and the face plate and the back plate are detected based on the detection result. A method of manufacturing an image forming apparatus, characterized in that alignment of the image forming apparatus is performed . The energy beam as a source for generating a manufacturing method of an image forming apparatus according to claim 1, characterized by using the electron source. 3. The method of manufacturing an image forming apparatus according to claim 2 , wherein the electron source has at least one element row formed by arranging and connecting a plurality of surface conduction electron-emitting devices.

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