JP2008243607A - Manufacturing method of airtight container, and manufacturing method of image display apparatus equipped with airtight container - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of an airtight container wherein high airtightness can be stably maintained. <P>SOLUTION: In this manufacturing method of the airtight container, a sealing material layer 32 is formed on the sealing face of the peripheral fringe of a front substrate 11 and the sealing surface of the peripheral fringe of a back substrate 12, and vacuum heat treatment is applied to the front substrate and the back substrate in which a metal-coated frame 18 is placed on one sealing material layer. A sealing material is fused and softened by heating the sealing material layer with the front substrate and the back substrate disposed so as to oppose each other without exposing them to the atmosphere, the front substrate and the back substrate are pressurized in their mutually approaching directions, and the peripheral fringes of the front substrate and the back substrate are thereby sealed. Before the vacuum heat treatment is applied to the front substrate and the back substrate, the metal-coated frame unit is heat-treated in advance at a temperature higher than a vacuum heat treatment temperature to degas it. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for manufacturing an airtight container having an envelope having a substrate disposed opposite to each other, and a large number of electron-emitting devices disposed in the envelope, and manufacturing an image display device including the airtight container. Regarding the method.

  In recent years, as a lightweight and thin image display device, a liquid crystal display (hereinafter referred to as LCD) that controls the intensity of light using the orientation of liquid crystal, a plasma display panel (hereinafter referred to as LCD) that emits phosphors by ultraviolet rays of plasma discharge. (Referred to as PDP), field emission display (hereinafter referred to as FED) that emits a phosphor with an electron beam of a field emission electron emitter, and surface conduction electron that emits a phosphor with an electron beam of a surface conduction electron emitter. Emission displays (hereinafter referred to as SEDs) have been developed.

  For example, FEDs and SEDs generally have a front substrate and a back substrate that are opposed to each other with a predetermined gap, and these substrates are vacuum-bonded by bonding their peripheral parts to each other via a rectangular frame. The envelope is configured. A phosphor screen is formed on the inner surface of the front substrate, and a number of electron-emitting devices are provided on the inner surface of the rear substrate as electron emission sources that excite the phosphor to emit light.

  In order to support an atmospheric pressure load applied to the back substrate and the front substrate, a plurality of support members are disposed between these substrates. The potential on the back substrate side is almost the ground potential, and an anode voltage is applied to the phosphor screen. The red, green, and blue phosphors that make up the phosphor screen are irradiated with electron beams emitted from a large number of electron-emitting devices, and the phosphors emit light to display an image.

  In such a display device, the thickness of the display device can be reduced to about several millimeters, and the weight and thickness can be reduced as compared with a CRT currently used as a display of a television or a computer. Can do.

  In the FED and SED as described above, the inside of the envelope needs to be in a high vacuum. As means for evacuating the envelope, a method has been proposed in which final assembly of the front substrate, the rear substrate and the frame constituting the envelope is performed in a vacuum chamber.

  In this method, the front substrate, the rear substrate, and the frame that are first arranged in the vacuum chamber are sufficiently heated. This is to reduce gas emission from the inner wall of the envelope, which is the main cause of the deterioration of the envelope vacuum. Next, when the front substrate, the rear substrate, and the frame are cooled and the degree of vacuum in the vacuum chamber is sufficiently improved, a getter film for improving and maintaining the degree of envelope vacuum is formed on the phosphor screen. . Thereafter, the front substrate, the rear substrate, and the frame are heated again to a temperature at which the sealing material dissolves, and cooled until the sealing material is solidified in a state where the front substrate and the rear substrate are combined at a predetermined position.

  The vacuum envelope created by such a method serves as a sealing step and a vacuum sealing step, and does not require time as in the case of exhausting the inside of the envelope using an exhaust pipe, and A very good degree of vacuum can be obtained.

  However, when assembling in such a vacuum, the processes performed in the sealing process range from heating, alignment, and cooling to a wide range, and the front substrate and the back surface for a long time during which the sealing material dissolves and solidifies. The substrate must be kept in place. In addition, there are problems in productivity and characteristics associated with sealing, such as the front substrate and the back substrate being thermally expanded and contracted due to heating and cooling at the time of sealing, and the alignment accuracy is likely to deteriorate.

On the other hand, a conductive low melting point metal sealing material such as indium that melts at a relatively low temperature is filled between the front substrate and the side wall, and this sealing material is energized to generate heat by the Joule heat A method of dissolving and bonding a pair of substrates and a frame (hereinafter referred to as energization heating) has been studied (for example, see Patent Document 1). According to this method, it is not necessary to spend an enormous amount of time for cooling the substrate, and it is possible to form the envelope by bonding the substrates in a short time.
JP 2002-319346 A

  In the conventional method described above, it is conceivable to use a metal frame as the frame. In this case, the manufacturing cost can be reduced as compared with the case where a glass frame is used as the frame. However, if the affinity between the metal frame and the sealing material is poor, it is difficult to reliably seal the substrates together, and there is a possibility that leakage may occur due to incomplete sealing. For this reason, a method has been proposed in which the surface of the frame is subjected to a surface treatment having good affinity with a sealing material such as Ag plating. By the way, in assembly in a vacuum using a metal frame, sealing is performed after a vacuum baking process in a state where the metal frame is previously placed on a front substrate or a back substrate filled with a sealing material. However, when the metal frame is placed on the substrate in advance and vacuum baked, the release gas is generated from the metal frame, so voids are generated in the sealing layer, resulting in leakage and deterioration of strength, and a high vacuum in the envelope. It is difficult to maintain the display device at a degree, and the display performance and life of the display device are deteriorated.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a method for manufacturing an airtight container capable of stably maintaining high airtightness, and a method for manufacturing an image display device including the airtight container. .

The manufacturing method of the airtight container which concerns on the aspect of this invention has the 1st board | substrate and 2nd board | substrate which were arrange | positioned oppositely, and the periphery of the said 1st board | substrate and the said 2nd board | substrate, and a sealing part, The sealing portion includes a metal-coated frame, and a sealing material layer filled between the frame and the first substrate and between the second substrate and the airtight container. Because
A sealing material layer is formed on the sealing surface at the peripheral edge of the first substrate and the sealing surface at the peripheral edge of the second substrate, and the metal-coated frame is placed on the one sealing material layer. The first substrate and the second substrate thus formed are subjected to a vacuum heat treatment, and the sealing material layer is heated and sealed in a state where the first substrate and the second substrate are arranged to face each other without being exposed to the atmosphere. The material is melted or softened, the first substrate and the second substrate are pressurized in a direction approaching each other, the peripheral portions of the first substrate and the second substrate are sealed, and the first substrate and the second substrate are sealed. Before the vacuum heat treatment, the metal-coated frame body is preliminarily heated at a temperature higher than the vacuum heat treatment temperature.

According to another aspect of the present invention, there is provided a method for manufacturing an image display device, comprising: a front substrate and a rear substrate that are arranged to face each other; and a sealing portion that surrounds the peripheral portions of the front substrate and the rear substrate. An image display device comprising an airtight container having a metal-coated frame and a sealing material layer filled between the frame and the front substrate and between the rear substrate and the attachment portion. A manufacturing method of
Forming a sealing material layer on the sealing surface of the peripheral portion of the front substrate and the sealing surface of the peripheral portion of the back substrate;
The front substrate and the back substrate on which the metal-coated frame body is placed on the one sealing material layer are subjected to vacuum heat treatment, and the front substrate and the back substrate are disposed to face each other without being exposed to the atmosphere. In this state, the sealing material layer is heated to melt or soften the sealing material, and the front substrate and the back substrate are pressurized in a direction approaching each other, and the peripheral portions of the front substrate and the back substrate are sealed. A method of manufacturing an image display apparatus, wherein the metal-coated frame body is preliminarily heated at a temperature higher than the vacuum heat treatment temperature before the front substrate and the back substrate are subjected to vacuum heat treatment. .

  According to the above configuration, the metal-coated frame body is preliminarily heat-treated at a temperature higher than the vacuum heat treatment temperature before sealing, thereby eliminating the released gas components remaining in the metal coating layer and the frame material. Therefore, it is possible to provide an airtight container that stably maintains high airtightness and a method for manufacturing an image display device including the airtight container.

Hereinafter, an embodiment in which an image display device according to the present invention is applied to an FED will be described in detail with reference to the drawings.
As shown in FIGS. 1 and 2, this FED includes a front substrate 11 and a rear substrate 12 each made of rectangular glass as insulating substrates, and these substrates are arranged to face each other with a predetermined gap. . The front substrate 11 and the back substrate 12 constitute a flat rectangular vacuum envelope 10 whose peripheral portions are bonded to each other via a rectangular frame-shaped side wall 18 and the inside is maintained in a vacuum state. The vacuum envelope 10 constitutes an airtight container.

  The peripheral portions of the front substrate 11 as the first substrate and the rear substrate 12 as the second substrate are joined to each other by the sealing portion 40. That is, the side wall 18 functioning as a frame is disposed between the sealing surface positioned at the inner peripheral edge of the front substrate 11 and the sealing surface positioned at the inner peripheral edge of the rear substrate 12. Further, between the front substrate 11 and the side wall 18 and between the back substrate 12 and the side wall 18, an underlayer 31 formed on the sealing surface of each substrate and an indium layer 32 formed on the underlayer. Are fused by a sealing layer 33 fused with each other. A sealing portion 40 is constituted by the sealing layer 33 and the side wall 18.

  In the present embodiment, the side wall 18 is made of a metal material, for example, a metal wire having a substantially circular cross section. The outer surface of the side wall 18 is covered with a metal coating, for example, a silver plating layer 19. The indium layer 32 is filled between the sealing surface of the front substrate 11 and the outer surface of the side wall 18 and between the sealing surface of the rear substrate 12 and the outer surface of the side wall.

  A plurality of plate-like support members 14 are provided inside the vacuum envelope 10 in order to support an atmospheric pressure load applied to the front substrate 11 and the rear substrate 12. These support members 14 extend in a direction parallel to one side of the envelope 10, for example, the long side, and are arranged at a predetermined interval along a direction orthogonal to the one side. . Both ends in the longitudinal direction of each support member 14 are opposed to the side wall 18 with a gap. Each support member 14 is attached to the back substrate 12, for example. The shape of the support member 14 is not particularly limited to this, and a columnar support member may be used.

  As shown in FIGS. 2 and 3, a phosphor screen 16 that functions as a display surface is formed on the inner surface of the front substrate 11. The phosphor screen 16 is configured by arranging red, green, and blue phosphor layers R, G, and B, and a black light shielding layer 20 positioned between these phosphor layers. The phosphor layers R, G, and B of three colors of red, green, and blue are formed alternately with a gap in the first direction, and the phosphor layers of the same color are in the second direction orthogonal to the first direction. Are arranged with a gap in between. Each of the phosphor layers R, G, and B constitutes a subpixel with single colors of red, green, and blue, and constitutes one pixel by combining the subpixels of three colors.

  A metal back layer 17 made of an aluminum film or the like is formed on the phosphor screen 16. According to the present embodiment, the metal back layer 17 has a plurality of divided regions that are divided in the vertical direction and the horizontal direction and are electrically separated from each other. The electrically separated metal back layer 17 is provided so as to overlap the phosphor layers R, G, and B, respectively. A getter film 13 is formed on the metal back layer 17.

  As shown in FIG. 2, a large number of electron-emitting devices that emit electron beams are provided on the inner surface of the back substrate 12 as electron sources that excite the phosphor layers R, G, and B of the phosphor screen 16. ing. That is, a conductive cathode layer 24 is formed on the inner surface of the back substrate 12, and a silicon dioxide film 26 having a large number of cavities 25 is formed on the conductive cathode layer. On the silicon dioxide film 26, a gate electrode 28 made of molybdenum, niobium or the like is formed. A cone-shaped electron-emitting device 22 made of molybdenum or the like is provided in each cavity 25 on the inner surface of the back substrate 12. These electron-emitting devices 22 are arranged in a plurality of columns and a plurality of rows corresponding to the pixels.

  The conductive cathode layer 24 and the gate electrode 28 are formed in stripes in directions orthogonal to each other, and a large number of wirings 23 (on the periphery of the back substrate 12 for supplying potentials to the conductive cathode layer and the gate electrode ( 1) is formed.

  In the FED configured as described above, a video signal is input to the electron-emitting device 22 and the gate electrode 28 formed in a simple matrix system. When the electron-emitting device 22 is used as a reference, a gate voltage of +100 V is applied when the luminance is highest. Further, +10 kV is applied to the phosphor screen 16. The magnitude of the electron beam emitted from the electron-emitting device 22 is modulated by the voltage of the gate electrode 28, and this electron beam excites the phosphor layer of the phosphor screen 16 to emit light, thereby displaying an image. .

Next, a method for manufacturing the FED configured as described above will be described in detail.
First, the phosphor screen 16 is formed on the plate glass to be the front substrate 11. In this method, a plate glass having the same size as the front substrate 11 is prepared, and a phosphor layer stripe pattern is formed on the plate glass by a plotter machine. The plate glass on which the phosphor stripe pattern is formed and the plate glass for the front substrate are placed on a positioning jig and set on an exposure table, whereby the phosphor screen 16 is generated by exposure and development.

Subsequently, the electron-emitting device 22 is formed on the glass plate for the rear substrate. In this case, a matrix-like conductive cathode layer is formed on the plate glass, and an insulating film of a silicon dioxide film is formed on the conductive cathode layer by, for example, a thermal oxidation method, a CVD method, or a sputtering method. Thereafter, a metal film for forming a gate electrode such as molybdenum or niobium is formed on the insulating film by, for example, sputtering or electron beam evaporation. Next, a resist pattern having a shape corresponding to the gate electrode to be formed is formed on the metal film by lithography. Using this resist pattern as a mask, the metal film is etched by wet etching or dry etching to form the gate electrode 28.
Since a high voltage is applied to the phosphor screen 16, high strain point glass is used for the front substrate 11, the rear substrate 12, and the plate glass for the support member 14.

  Subsequently, the cavity 25 is formed by etching the insulating film by wet etching or dry etching using the resist pattern and the gate electrode as a mask. After removing the resist pattern, a peeling layer made of, for example, aluminum or nickel is formed on the gate electrode 28 by performing electron beam evaporation from a direction inclined at a predetermined angle with respect to the back substrate surface. Thereafter, for example, molybdenum is deposited as a material for forming the cathode from the direction perpendicular to the surface of the back substrate by an electron beam deposition method. As a result, the electron-emitting device 22 is formed inside each cavity 25. Subsequently, the release layer is removed together with the metal film formed thereon by a lift-off method.

Subsequently, the plurality of support members 14 are sealed with the low melting point glass 30 in the air on the back substrate 12 on which the electron-emitting devices 22 are formed.
Next, the side wall 18 disposed at the peripheral edge of the substrate is formed. The side wall 18 is formed of a metal round bar or wire having a circular cross section as the core material 15 and a plating layer 19 as a metal coating covering the outer surface of the core material. As the core material 15, a NiFe alloy having a thermal expansion coefficient substantially equal to that of the glass constituting the substrate was used. Further, Ag was used as the plating layer 19.

  When the side wall 18 is formed, first, the core material 15 is bent into a rectangular frame shape according to a required size. The bent portions are three portions corresponding to the three corners of the side wall. A portion corresponding to the remaining one corner of the side wall 18 is formed by welding both ends of a round bar or a wire to each other by a laser welding machine. At this time, the side wall is produced by instantaneously melting only the welded portion with a laser welding machine. In addition, it is desirable that unevenness does not remain at the connection portion during welding, but if unevenness is generated, it can be used as a side wall by flattening with a gold file or the like.

  Next, an Ag plating process is performed on the surface of the core material 15. First, the NiFe alloy core 15 is washed with pure water and alcohol and dried. And the core material 15 is put into a plating solution tank, and about 0.1-7 micrometers of Ag plating layers 19 are formed by an electrolytic plating process. Thereafter, the core material 15 on which the plating layer 19 is formed is washed with pure water and alcohol and dried. Here, in order to increase the affinity and adhesion between the NiFe alloy and the Ag plating, the surface of the core material 15 is blasted to form irregularities before plating. Here, the unevenness is about 0.05 μm. Alternatively, before the plating treatment, Ni plating or Cu plating may be formed on the surface of the core member 15 and then the plating layer 19 may be formed on the plating layer.

  Next, in order to perform degassing, vacuum heat treatment is performed. If this process is a process for lowering the pressure in the vacuum envelope in order to stabilize the electron source characteristics and prolong the life, only the vacuum heating process just before the sealing step is sufficient. However, if a vacuum heating process is performed immediately before the sealing step with the side wall 18 placed on the substrate filled with the sealing layer, voids are generated in the sealing layer. As this cause, generation | occurrence | production of the emitted gas from the side wall 18 can be considered. Therefore, the side wall 18 is previously vacuum-heated alone to degas. The higher the vacuum heat treatment temperature of the side wall 18 is, the better. The upper limit value of the treatment temperature is 850 ° C. which is a limit temperature at which Ag of the plating layer 19 does not evaporate, and the lower limit value is 500 ° C. at which the amount of released gas increases. Desirably, it was 600-800 degreeC, and it processed by 750 degreeC / 10min in this embodiment.

  FIG. 4 shows a comparison of the amount of gas released when heat treatment is performed on a side wall obtained by coating the FeNi metal wire with gold plating in this embodiment and another material. As a comparative material, an unplated FeNi metal wire and two types of silver plating layers were used. As can be seen from this figure, the metal wire alone emits an almost constant amount of gas in the range of 200 to 600 ° C., whereas in the case of a metal wire covered with a silver plating layer, it is around 500 ° C. After outgassing begins, a rapid outgassing occurs up to about 580 ° C. Thereafter, the amount of gas released gradually decreases to around 900 ° C. With the silver plating alone, almost no gas release is observed. Note that most of the released gas is hydrogen.

  From the above, the side wall 18 alone is preliminarily heat-treated at 500 to 850 ° C., so that the side wall can be sufficiently degassed. In the subsequent sealing step, the side wall 18 is caused by the gas released from the side wall. Generation of voids can be prevented.

  Next, as shown in FIG. 5, a silver paste is applied to the sealing surface located at the inner peripheral edge of the front substrate 11 and the sealing surface located at the inner peripheral edge of the rear substrate 12 by screen printing. Then, a frame-shaped underlayer 31 is formed. Subsequently, indium as a conductive metal sealing material is applied on each base layer 31 to form an indium layer 32 extending over the entire circumference of the base layer.

  As the metal sealing material, it is desirable to use a low-melting-point metal material having a melting point of about 350 ° C. or less and excellent adhesion and bondability. Indium (In) used in this embodiment has not only a low melting point of 156.7 ° C., but also has excellent characteristics such as low vapor pressure, soft and strong against impact, and does not become brittle even at low temperatures. Moreover, since it can be directly bonded to glass depending on conditions, it is a material suitable for the purpose of this embodiment.

  Next, as shown in FIG. 6, the support member 14 is fixed and the back substrate 12 in which the base layer 31 and the indium layer 32 are formed on the sealing surface, and the side wall 18 is placed on the indium layer 32. The front substrate 11 is held by a jig or the like in a state where the sealing surfaces face each other and face each other with a predetermined distance. At this time, for example, the front substrate 11 is placed upward and disposed below the rear substrate 12. In this state, the front substrate 11 and the back substrate 12 are put into a vacuum processing apparatus.

  As shown in FIG. 7, the vacuum processing apparatus 100 includes a load chamber 101, a baking, an electron beam cleaning chamber 102, a cooling chamber 103, a getter film deposition chamber 104, an assembly chamber 105, and a cooling chamber 106 that are arranged in order. , An unload chamber 107, a driving device 120 for adjusting the temperature and vacuum degree of each chamber, and a control unit 121 for controlling the operation of the entire device. Each of these chambers is configured as a processing chamber capable of vacuum processing, and all the chambers are evacuated when the FED is manufactured. Adjacent processing chambers are connected by a gate valve or the like.

The front substrate 11 and the rear substrate 12 on which the side walls 18 are placed are put into the load chamber 101, and after the inside of the load chamber 101 is evacuated, it is sent to the baking and electron beam cleaning chamber 102. In the baking and electron beam cleaning chamber 102, when the high vacuum degree of about 10 ⁻⁵ Pa is reached, the back substrate and the front substrate are baked by heating to a temperature of about 300 ° C. to 450 ° C. Fully release the adsorbed gas.

  At this temperature, the indium layer (melting point: about 156 ° C.) 32 is melted. At this time, since the indium layer 32 is formed on the base layer 31 having high affinity, the indium is held on the base layer without flowing. Then, the sidewall 18 and the front substrate 11 are joined by the molten indium. Hereinafter, the front substrate 11 to which the side walls 18 are bonded is referred to as a front substrate side assembly.

  In the baking and electron beam cleaning chamber 102, simultaneously with heating, an electron beam is irradiated from a not-shown electron beam generator onto the phosphor screen surface of the front substrate side assembly and the electron emitting element surface of the rear substrate 12. . Since this electron beam is deflected and scanned by a deflection device mounted outside the electron beam generator, the entire surface of the phosphor screen and the surface of the electron-emitting device can be cleaned with an electron beam.

  After heating and electron beam cleaning, the front substrate assembly and the rear substrate 12 are sent to the cooling chamber 103 and cooled to a temperature of about 100 ° C., for example. Subsequently, the front substrate side assembly and the rear substrate 12 are sent to a getter film deposition chamber 104 where a Ba film is deposited on the phosphor screen 16 and the metal back layer 17 as a getter film. The Ba film is prevented from being contaminated with oxygen, carbon, or the like, and can maintain an active state.

  Next, the front substrate side assembly and the rear substrate 12 are sent to the assembly chamber 105 where they are heated to 200 ° C. As a result, the indium layer 32 is again melted or softened into a liquid state. In this state, the side wall 18 and the back substrate 12 are bonded to each other with the indium layer 32 interposed therebetween, and pressurized with a predetermined pressure in a direction approaching each other. At this time, a part of the pressurized molten indium tends to flow in the direction of the display area or wiring area of the back substrate 12, but the side wall 18 has a circular cross section, so that the molten indium is in the back substrate 12. This prevents the flow from flowing to the display region side or the wiring region side beyond the width of the side wall. Also in the front substrate side assembly, the remelted indium stays at a wide space between the sealing surface of the front substrate 11 and the outer surface of the side wall 18 and prevents it from flowing to the display region side or outside beyond the width of the side wall. Is done. Accordingly, indium is maintained within the maximum width of the cross section of the side wall 18 on both the front substrate 11 side and the back substrate 12 side.

Thereafter, the indium is cooled and solidified. Thereby, the back substrate 12 and the side wall 18 are sealed by the sealing layer 33 in which the indium layer 32 and the base layer 31 are fused. At the same time, the front substrate 11 and the side wall 18 are sealed by the sealing layer 33 in which the indium layer 32 and the base layer 31 are fused, and the vacuum envelope 10 is formed.
The vacuum envelope 10 formed in this way is cooled to room temperature in the cooling chamber 106 and then taken out from the unload chamber 107. Through the above steps, an FED vacuum envelope whose inside is maintained at a high vacuum is obtained.

  According to the FED configured as described above and the manufacturing method thereof, the front substrate 11 and the rear substrate 12 are sealed in a vacuum atmosphere, so that the surface adsorption gas on the substrate can be sufficiently obtained by the combined use of baking and electron beam cleaning. The getter film is not oxidized and a sufficient gas adsorption effect can be obtained. Thereby, FED which can maintain a high degree of vacuum can be obtained.

  Further, the side wall 18 constituting the sealing portion 40 is formed by covering the core material 15 with a plating layer 19, and this plating layer has a very good affinity with indium as a sealing material. Therefore, it is possible to reliably seal between the front substrate 11 and the side wall 18 and between the back substrate 12 and the side wall. Furthermore, the side wall 18 is preliminarily heated at a temperature higher than the temperature at the time of sealing, and degassing is performed, thereby preventing the generation of released gas from the side wall and the plating layer at the time of sealing the side wall. Generation of voids in the sealing portion 40 can be prevented. Thereby, generation | occurrence | production of the leak in the sealing part 40 can be prevented, and a highly airtight vacuum envelope can be obtained. As a result, an image display device that maintains a high degree of vacuum and exhibits excellent display performance over a long period of time can be obtained. Furthermore, according to the said structure, even if it is a large image display apparatus of 50 inches or more, it can seal easily and reliably by using the frame which shape | molded the metal wire and the metal rod as a side wall, and was excellent. Mass productivity can be obtained.

  In the above-described embodiment, the NiFe alloy is used as the core material 15. However, the present invention is not limited to this, as long as the plating process is possible and the thermal expansion coefficients of the front substrate and the rear substrate are relatively close. For example, a metal such as a simple substance or an alloy containing any of Fe, Ni, and Ti can be used. The sealing material is not limited to indium, and may be any low melting point metal material having a melting point of about 350 ° C. or less and having adhesiveness and bonding properties, and may be a metal containing any of Ga, Sn, and Bi or an alloy thereof. . Further, the plating layer 19 is not limited to Ag, and may have high affinity with a sealing material and excellent airtightness. At least one of Au, Cu, Pt, Ni, In, and Sn may be used. The metal or alloy containing can be used. Furthermore, the method of forming the metal coating on the core material of the frame is not limited to the plating process, and a vapor deposition process such as CVD or PVD or a sputtering process may be used.

Moreover, the heat treatment of the side wall 18 alone may be performed not only in a vacuum atmosphere but also in a stable gas atmosphere such as N 2 or Ar. Furthermore, when a metal material that does not easily oxidize, such as Ag, is used for the surface treatment of the side wall, it may be heat-treated in the atmosphere. In the above-described embodiment, the cross-sectional shape of the side wall 18 is circular, but is not limited thereto, and may be a rectangular frame or the like.
In the above-described embodiment, when the front substrate and the rear substrate are bonded, these substrates are heated to about 200 ° C. in the assembly chamber to melt or soften the indium layer. Instead of heating the entire substrate, The indium layer may be melted or softened by energization heating. That is, the front substrate and the back substrate are pressed in a direction approaching each other and the side wall is sandwiched between the indium layers, and the side wall 18 is energized to generate heat by Joule heat. It is good also as a structure to wear. In this case, the side wall 18 is formed of a conductive material.
In addition, the present invention is not limited to the above-described embodiments as they are, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

  For example, the manufacturing method of the hermetic container according to the present invention can be applied not only to the envelope of the image display device but also to other hermetic containers such as electronic devices. In the above-described embodiment, the field emission type electron emission element is used as the electron emission element. However, the present invention is not limited to this, and other electron emission elements such as a pn type cold cathode element or a surface conduction type electron emission element are used. It may be used. The present invention is not limited to a display device that requires a vacuum envelope such as an FED or SED, but can be applied to other image display devices such as PDP electroluminescence (EL).

FIG. 1 is a perspective view showing a partially broken FED according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of the FED along line AA in FIG. FIG. 3 is a plan view showing the phosphor screen of the FED. FIG. 4 is a diagram showing a comparison between the heating temperature of the side wall of the FED and other members and the amount of gas released. FIG. 5 is a perspective view showing a state in which a base layer and an indium layer are formed on the sealing surface of the rear substrate and the sealing surface of the front substrate that constitute the vacuum envelope of the FED. FIG. 6 is a cross-sectional view showing a state where a rear substrate having a base layer and an indium layer formed on the sealing portion and a front substrate assembly are arranged to face each other. FIG. 7 is a diagram schematically showing a vacuum processing apparatus used for manufacturing the FED.

Explanation of symbols

10 ... Vacuum envelope, 11 ... Front substrate, 12 ... Rear substrate,
13 ... side wall, 14 ... support member, 15 ... core material,
16 ... phosphor screen, 19 ... plating layer,
22 ... an electron-emitting device, 31 ... an underlayer, 32 ... an indium layer,
33 ... sealing layer, 40 ... sealing part, 100 ... vacuum processing apparatus

Claims (10)

A first substrate and a second substrate disposed opposite to each other, and a peripheral portion of the first substrate and the second substrate, and a sealing portion, and the sealing portion includes a metal-coated frame, A method for producing an airtight container having a sealing material layer filled between the frame and the first substrate and between the second substrate,
Forming a sealing material layer on the sealing surface of the peripheral portion of the first substrate and the sealing surface of the peripheral portion of the second substrate;
The first substrate and the second substrate on which the metal-coated frame body is placed on the one sealing material layer are subjected to vacuum heat treatment,
In a state where the first substrate and the second substrate are arranged to face each other without being exposed to the atmosphere, the sealing material layer is heated to melt or soften the sealing material, and the first substrate and the second substrate And pressurizing in a direction approaching each other, sealing the peripheral edge of the first substrate and the second substrate,
A method for manufacturing an airtight container, in which the metal-coated single frame body is heated in advance at a temperature higher than the vacuum heat treatment temperature before the first substrate and the second substrate are subjected to a vacuum heat treatment.   The manufacturing method of the airtight container of Claim 1 which heat-processes the said metal-coated frame in a vacuum atmosphere.   The manufacturing method of the airtight container of Claim 1 which heat-processes the said metal-coated frame at 400-850 degreeC.   The manufacturing method of the airtight container of Claim 1 which heat-processes the said metal-coated frame at 600-800 degreeC.   The method of manufacturing an airtight container according to claim 1, wherein the metal coating of the frame is formed by plating.   The manufacturing method of the airtight container of Claim 1 which forms the metal coating | cover of the said frame with silver, and heat-treats the said frame in air | atmosphere.   The method for manufacturing an airtight container according to claim 1, wherein the sealing material is Sn, In, Bi, or an alloy thereof.   The method of manufacturing an airtight container according to claim 1, wherein the frame is formed of an alloy containing Ni and Fe.   After forming a base layer having affinity for the sealing material on the sealing surface at the peripheral edge of the front substrate and the sealing surface at the peripheral edge of the back substrate, the sealing material is formed on the base layer. The manufacturing method of the airtight container of Claim 1 which forms a layer. A front substrate and a rear substrate disposed opposite to each other, and peripheral portions of the front substrate and the rear substrate are sealed to each other, and the sealing portion includes a metal-coated frame and the frame. A method of manufacturing an image display device including an airtight container having a sealing material layer filled between the front substrate and the back substrate,
Forming a sealing material layer on the sealing surface of the peripheral portion of the front substrate and the sealing surface of the peripheral portion of the back substrate;
The front substrate and the rear substrate on which the metal-coated frame body is placed on the one sealing material layer are subjected to vacuum heat treatment,
In a state where the front substrate and the back substrate are arranged to face each other without being exposed to the atmosphere, the sealing material layer is heated to melt or soften the sealing material, and the front substrate and the back substrate are brought close to each other. Pressurizing in the direction, sealing the periphery of the front substrate and the back substrate,
A method of manufacturing an image display device, in which the metal-coated frame body is preliminarily heated at a temperature higher than the vacuum heat treatment temperature before the front substrate and the rear substrate are vacuum heat treated.

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