JP2005243684A - Cooling method of substrate, method of manufacturing vacuum housing, substrate cooling device and apparatus of manufacturing vacuum housing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide the cooling method of a substrate which can stably cool the substrate in a short time while maintaining the temperature of the entire substrate uniform, and to provide a substrate cooling device. <P>SOLUTION: The cooling method of the substrate includes the steps of dividing cooling plates 2a, 2b into nine in all to a substrate region, dividing them into four regions and controlling the temperature so that the temperature become higher toward the periphery of the substrate, and cooling the substrate in the state that the substrate temperature is maintained uniformly. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a heat-treated substrate cooling method and a substrate cooling apparatus, and more particularly to a substrate cooling method and a substrate cooling apparatus suitable for cooling a large substrate used in a flat display device or the like. Furthermore, the present invention relates to a manufacturing method and a manufacturing apparatus for a vacuum envelope that are suitable for use in manufacturing a flat rectangular vacuum envelope by joining peripheral portions of a front substrate and a rear substrate via side walls. .

  In recent years, processes for efficiently heating and cooling a substrate have been developed in fields such as semiconductors and flat panel displays. Conventionally, as a technique for cooling a heat-treated substrate, there have been a structure in which a cooling water channel is provided in a cooling chamber to quickly cool, a structure in which liquid nitrogen is passed through a cooling pipe, and the substrate is rapidly cooled. However, there has been no stable and reliable cooling technique regarding the flat surface accuracy of the substrate when the heat-treated substrate is cooled.

In cooling the substrate, the substrate must be cooled while keeping the substrate temperature uniform in order to prevent the substrate from warping or breaking. Generally, the heat radiation of the substrate is larger in the peripheral portion than in the central portion, and the substrate temperature is distributed such that the temperature decreases from the center to the periphery. When the size (plate area) of the substrate is small, the temperature distribution is also small. Therefore, even with the cooling means according to the prior art, the warp and breakage of the substrate are not a problem. However, when the size of the substrate is large, the difference in heat dissipation between the central portion and the peripheral portion cannot be ignored, which has been a problem in recent years. In particular, in the case of flat display, since the shape of the substrate is generally rectangular, the heat radiation at the corner portion is further increased, and thus the case where the temperature of the corner portion is lower than the central portion by 20 ° C. or more has occurred. This is particularly remarkable when the substrate is rapidly cooled as in the prior art described above. As an example of such a large rectangular substrate, there is a field emission display (hereinafter referred to as FED) in which a phosphor emits light by an electron beam of a field emission type electron-emitting device. In the FED, a baking process is performed in which various members are heated to a temperature of 400 ° C. to release surface adsorbed gas in the manufacturing process so that unnecessary gas is not generated during operation. At this time, since the temperature distribution cannot be kept uniform with the conventional substrate cooling technology, the thermal expansion of the substrate becomes non-uniform, and the elements and wiring on the substrate are destroyed due to the bending and warping of the substrate. There has been a problem that a spacer for maintaining the withstand voltage is detached from the substrate.
JP 7-216550 A

  As described above, conventionally, there has been no stable and reliable technique for maintaining high flat surface accuracy with respect to a cooling technique for a heat-treated substrate. In particular, since the temperature distribution cannot be kept uniform with the conventional substrate cooling technology, the thermal expansion of the substrate becomes non-uniform, the elements and wiring on the substrate are destroyed, and the spacer for maintaining the vacuum withstand voltage is detached from the substrate. Or other problems occurred.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a substrate cooling method and a substrate cooling apparatus capable of stably cooling in a short time while maintaining the temperature of the entire substrate uniform. .

  The present invention provides a substrate cooling method in which a heat-treated substrate is cooled to a predetermined temperature by a cooling means, wherein the cooling means cools the substrate according to a temperature condition set for each of a plurality of regions of the substrate. It is characterized by.

  The present invention also relates to a vacuum envelope manufacturing method for manufacturing a flat rectangular vacuum envelope by joining peripheral portions of a front substrate and a back substrate through side walls, and heating each substrate. And a cooling step of lowering the temperature of the heated substrate to a predetermined temperature while equalizing the temperature of the entire substrate.

  The present invention also provides a substrate cooling apparatus for cooling a heat-treated substrate to a predetermined temperature by a cooling means, comprising cooling means for cooling the heat-treated substrate according to temperature conditions set for each of a plurality of regions of the substrate. It is characterized by that.

  Further, the present invention provides a vacuum envelope manufacturing apparatus that manufactures a flat rectangular vacuum envelope by joining peripheral portions of a front substrate and a rear substrate through side walls, and sets each substrate in advance. Heat treatment means for heating to the above-mentioned temperature; and cooling treatment means for lowering the temperature of the heat-treated substrate to a predetermined temperature while equalizing the temperature of the entire substrate.

  According to the above-described method and apparatus of the present invention, when the heat-treated substrate is cooled to a predetermined temperature, the temperature variation of the substrate can be absorbed, whereby the thermal expansion of the substrate becomes uniform, and the elements on the substrate and Problems such as the destruction of the wiring and the separation of the spacer for maintaining the vacuum withstand voltage from the substrate can be suppressed. Therefore, it is possible to stably cool in a short time while maintaining the temperature of the entire substrate uniform.

  According to the present invention, the substrate can be cooled while the temperature is equalized, and the thermal expansion of the substrate can be made uniform. As a result, problems such as destruction of elements and wiring on the substrate that have occurred in the past and spacers for maintaining vacuum withstand pressure coming off from the substrate can be suppressed, and the temperature of the entire substrate can be kept uniform. However, it can cool stably in a short time.

  A substrate cooling apparatus according to the present invention will be described below with reference to the drawings.

  FIG. 1 shows the structure of the main part of the cooling device according to the first embodiment of the present invention. In FIG. 1, two sets of cooling plates 2 a and 2 b are arranged at a predetermined distance apart from each other in an airtightly sealed cooling device 1. The cooling plates 2a and 2b provided in the cooling device 1 have a cooling region that covers the entire substrate surface with respect to the substrate to be cooled. The inside of the cooling device 1 is evacuated by a vacuum pump so as to be maintained between 1.0 × 10 −5 and 1.0 × 10 −4 Pa. Since the evacuation system, the cooling plate holding mechanism, and the substrate transfer mechanism are not the essence of the present invention, they are not shown.

  FIG. 2 is a front view of the cooling plate 2 a provided inside the cooling device 1. In this example, the cooling plate 2a is divided into nine parts according to the central part, the long side part, the short side part, and the corner part of the substrate to be cooled, and a cooling channel is provided as a temperature control means for each. The temperature can be controlled corresponding to the following areas.

First region 41: Substrate center region Second region 42: Substrate long side region Third region 43: Substrate short side region Fourth region 44: Substrate corner region In this embodiment, the temperature is controlled for each of the above regions. Thus, for example, the two cooling plate members in the second region 42 are simultaneously controlled so as to have the same temperature.

  FIG. 3 is a front view of the cooling plate 2 b provided inside the cooling device 1. This cooling plate 2b is also divided into nine parts in accordance with the substrate area in the same manner as the cooling plate 2a described above, and each has a cooling channel as temperature control means, and controls the temperature corresponding to the following areas, respectively. Can be done.

First region 51: Substrate central region Second region 52: Substrate long side region Third region 53: Substrate short side region Fourth region 54: Substrate corner region Inside the first regions 41, 51 of each of the cooling plates 2a, 2b 4 is provided with a cooling pipe 3 as temperature control means as shown in FIG. 4, and by circulating cooling water through the cooling pipe 3, the first regions 41 and 51 of the cooling plates 2a and 2b are fixed. The temperature can be kept. Further, as shown in FIG. 5, a sheath heater 4 and a cooling pipe 5 are provided inside the second to fourth regions 42 to 44 and 52 to 54 of the cooling plates 2a and 2b as temperature control means. ing. Cooling can be performed by circulating air through the cooling pipe 5, and the temperature of these cooling plates can be varied by heating by the sheath heater 4 and cooling by the cooling pipe 5.

  Aluminum is used as the material of these cooling plates, and the surface is subjected to a surface treatment for increasing the emissivity in order to increase the cooling efficiency. Examples of the surface treatment include black anodizing treatment and thermal spraying of an alumina thin film.

  Next, a method for cooling the substrate by the cooling device 1 will be described with reference to FIGS.

  The substrate heated to 400 ° C. in a vacuum atmosphere in order to release the surface adsorption gas in the heat treatment chamber adjacent to the above-described cooling device 1 is transferred to the cooling device 1 while maintaining the vacuum state, and is shown in FIG. As shown, it is installed between the cooling plates 2a, 2b. In FIG. 6, the jig for holding the substrate 6 between the cooling plates 2a and 2b is not shown. When the transfer of the substrate 6 is completed, the cooling plates 2a and 2b are set to have the following temperatures.

First region 41, 51: 20 ° C
Second region 42, 52: 415 ° C
Third region 43, 53: 415 ° C
Fourth region 44, 54: 420 ° C.
After this, by continuing to circulate cooling water through the cooling pipe 3, the first regions 41 and 51 of the cooling plates 2a and 2b are kept at 20 ° C. In addition, air circulation to the cooling pipe 5 is started, and at the same time, the current to the sheath heater 4 is weakened to lower the temperature of the second, third, and fourth regions of the cooling plates 2a and 2b. At this time, the fourth region is a region corresponding to the substrate corner, and since this region has the greatest heat dissipation, the temperature is lowered so that the temperature becomes relatively high. Next, the heat radiation is large in the second region corresponding to the long side of the substrate, and the temperature of the second region is lowered so as to be relatively higher than that in the third region. In addition, since each of the corresponding regions of the cooling plates 2a and 2b has one inserted substrate, the temperature is lowered so as to be the same temperature. FIG. 7 shows the temperature lowering history of the cooling plates 2a and 2b in these temperature controls. As shown in FIG. 7, the temperature lowering conditions are set so that the substrate temperature becomes uniform. As a result, the substrate temperature is cooled as shown in FIG.

  In FIG. 8, a curve 111 is temperature measurement data at the substrate position corresponding to each of the four regions of the cooling plates 2a and 2b. However, as shown in the figure, there is almost no temperature difference and the cooling is performed by overlapping. Understand. A curve 112 is a plot of the difference between the highest temperature and the lowest temperature of the temperature distribution in the substrate surface. In this embodiment, this temperature difference is within 2.5 ° C. That is, the cooling plates 2a and 2b are each divided into nine parts according to the substrate region, and these are divided into four regions to control the temperature, whereby it is possible to cool the substrate while keeping the substrate temperature uniform.

Next, a second embodiment of the present invention will be described.
In the second embodiment, the configuration of the cooling device and the cooling plate is the same as that of the first embodiment, but the number of transferred substrates is two. Here, as shown in FIG. 9, two substrates 6 and 7 are disposed between the cooling plates 2a and 2b.

  When the transfer of the substrates 6 and 7 into the cooling device 1 is completed, the cooling plates 2a and 2b are set to have the following temperatures.

1st area | region 41 of the cooling plate 2a: 20 degreeC
Second region 42 of the cooling plate 2a: 415 ° C.
3rd area | region 43 of cooling plate 2a: 415 degreeC
4th area | region 44 of cooling plate 2a: 425 degreeC
1st area | region 51 of the cooling plate 2b: 20 degreeC
Second region 52 of cooling plate 2b: 410 ° C.
3rd area | region 53 of the cooling plate 2b: 410 degreeC
4th area | region 54 of cooling plate 2b: 415 degreeC
In the present embodiment, the lower substrate 7 is larger in size (plate area) than the upper substrate 6, so that heat radiation at the side and corner portions of the lower substrate 7 is greater than that of the upper substrate 6. growing. For this reason, the temperature is lowered so that the temperature of the lower cooling plate 2a becomes higher than the temperature of the corresponding upper cooling plate 2b. Also in this embodiment, by continuing to circulate the cooling water through the cooling pipe 3, the first regions 41 and 51 are kept at 20 ° C., and the atmospheric circulation to the cooling pipe 5 is started to supply the sheath heater 4 to the sheath heater 4. The cooling plates in the second, third, and fourth regions are cooled by weakening the energization. In the fourth region, since the heat radiation of the substrate is the largest, the temperature is lowered so that the temperature becomes relatively high. As a result, the cooling history of the cooling plate is as shown in FIG. As shown in FIG. 10, the temperature lowering conditions of the cooling plates 2a and 2b are set so that the temperatures of the two substrates 6 and 7 are uniform. As a result, the substrate temperature is cooled as shown in FIG. The

  In FIG. 11, a curve 113 is temperature measurement data at the substrate position corresponding to each of the divided areas of the two cooling plates 2a and 2b. Understand. A curve 114 is a plot of the difference between the maximum temperature and the minimum temperature of the substrate surface temperature distribution. In this embodiment, this temperature difference is within 3.0 ° C. In other words, the two cooling plates 2a and 2b are divided into nine parts according to the substrate area, respectively, and these are divided into four areas, respectively, so that the temperature can be controlled while maintaining the substrate temperature uniform. Became.

  Next, a case where the above-described embodiment is applied to an FED will be described below with reference to FIGS.

  As shown in FIG. 12, the FED includes a front substrate 11 and a rear substrate 12 each made of a rectangular glass plate, and these substrates 11 and 12 are arranged to face each other at a predetermined interval. The back substrate 12 is formed to have a size larger than that of the front substrate 11. The front substrate 11 and the back substrate 12 constitute a flat rectangular vacuum envelope 10 whose peripheral portions are joined to each other via a rectangular frame-shaped side wall 18 and the inside is maintained in a vacuum state. .

  As shown in FIG. 13, 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 vacuum envelope 10 and are arranged at a predetermined interval along a direction orthogonal to the one side.

  As shown in FIG. 14, a phosphor screen 16 that functions as an image display surface is formed on the inner surface of the front substrate 11. As shown in FIG. 15, the phosphor screen 16 is configured by arranging red, green, and blue phosphor layers R, G, and B, and a black light absorbing layer 20 positioned between these phosphor layers. The phosphor layers R, G, and B extend in a direction parallel to the one side of the vacuum envelope 10 and are arranged at a predetermined interval along a direction orthogonal to the one side. As shown in FIG. 14, a metal back layer 17 made of aluminum and a getter film 13 made of barium, for example, are formed on the phosphor screen 16.

  On the inner surface of the back substrate 12, a large number of electron-emitting devices 22 that emit electron beams are provided as electron-emitting sources that excite the phosphor layer of the phosphor screen 16. These electron-emitting devices 22 are arranged in a plurality of columns and a plurality of rows corresponding to each pixel. More specifically, 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. The conductive cathode layer and the gate electrode are formed in stripes in directions orthogonal to each other, and a large number of wirings 23 for supplying a potential to the conductive cathode layer and the gate electrode are provided on the peripheral portion of the back substrate 12. 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 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. Thereby, an electron beam is emitted from the electron emitter 22. The magnitude of the electron beam emitted from the electron-emitting device 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.

The above-mentioned FED is manufactured as follows.
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 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. In this state, the phosphor screen is formed on the glass plate which becomes the front substrate 11 by exposing and developing. Thereafter, a metal back layer 17 is formed on the phosphor screen 16.

  Subsequently, the electron-emitting device 22 is formed on the plate glass for the back substrate 12. First, a conductive cathode layer 24 is formed on a plate glass, and an insulating film of a silicon dioxide film is formed on the 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.

  After that, the cavity 25 is formed by etching the insulating film by wet etching or dry etching using the resist pattern and the gate electrode 28 as a mask. Then, 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 by a predetermined angle with respect to the back substrate surface. After that, for example, molybdenum is deposited by electron beam deposition as a material for forming the cathode from a direction perpendicular to the surface of the back substrate. As a result, the electron-emitting device 22 is formed inside the cavity 25. Next, the release layer is removed together with the metal film formed thereon by a lift-off method.

  Subsequently, the side wall 18 and the support member 14 are sealed on the inner surface of the back substrate 12 by the low melting point glass 19 in the atmosphere. Thereafter, indium is filled to a predetermined width and thickness over the entire circumference of the sealing surface of the side wall 18. Similarly, a sealing surface facing the side wall of the front substrate 11 is filled with indium in a rectangular frame shape with a predetermined width and thickness. The sealing layer is filled into the sealing surface of the side wall 18 and the front substrate 11 by a method of applying molten indium to the sealing surface or a method of placing solid indium on the sealing surface. .

  Then, as shown in FIG. 16, a pair of electrodes 30a and 30b are attached to the back substrate 12 to which the side walls 18 are bonded. These are attached in a state of being elastically engaged with the back substrate 12. That is, the electrodes 30 a and 30 b are attached to the vacuum envelope 10 in a state where the peripheral portion of the back substrate 12 is elastically held by the clip portion 32. At this time, the electrodes are electrically connected to the sealing layer by bringing the contact portions 36 of the electrodes 30 a and 30 b into contact with the sealing layer on the side wall 18. Each of the electrodes 30a and 30b is used as an electrode when energizing the sealing layer 21, and requires a pair of a positive electrode and a negative electrode on the substrate, and is a sealing layer that is energized in parallel between the pair of electrodes. It is desirable that each energization path has the same length. Therefore, the pair of electrodes 30 are attached to the two corners facing the diagonal direction of the back substrate 12, and the length of the sealing layer positioned between the electrodes is set to be approximately equal on both sides of each electrode. .

  After the electrodes 30a and 30b are mounted, the rear substrate 12 and the front substrate 11 are arranged to face each other with a predetermined distance between them, and in this state, they are put into a vacuum processing apparatus. Here, for example, a vacuum processing apparatus 100 as shown in FIG. 17 is used. The vacuum processing apparatus 100 includes a load chamber 101, baking, an electron beam cleaning chamber 102, a cooling chamber 103, a getter film deposition chamber 104, an assembly chamber 105, a cooling chamber 106, and an unload chamber 107 arranged side by side. ing. Connected to the assembly chamber 105 are a DC power supply 120 for energization and a computer 121 for controlling the power supply. Each chamber of the vacuum processing apparatus 100 is configured as a processing chamber capable of vacuum processing, and all the chambers are evacuated when the FED is manufactured. These processing chambers are connected by a gate valve or the like (not shown).

  The above-described front substrate 11 and rear substrate 12 that are spaced apart by a predetermined distance are first put into the load chamber 101. Then, after the atmosphere in the load chamber 101 is changed to a vacuum atmosphere, it is sent to the baking and electron beam cleaning chamber 102.

  In the baking and electron beam cleaning chamber 102, various members are heated to a temperature of 400 ° C. to release the surface adsorption gas of each substrate. At the same time, an electron beam is irradiated onto the phosphor screen surface of the front substrate 11 and the electron-emitting device surface of the rear substrate 12 from an electron beam generator (not shown) attached to the baking and electron beam cleaning chamber 102. At that time, the electron beam is deflected and scanned by a deflection device mounted outside the electron beam generator, whereby the entire surfaces of the phosphor screen surface and the electron-emitting device surface are respectively cleaned with the electron beam.

  The front substrate 11 and the back substrate 12 that have been degassed are sent to the cooling chamber 103 and cooled to a temperature of about 120 ° C. by the cooling method described in the second embodiment. In this cooling method, for example, the cooling plates 2a and 2b are divided into nine parts according to the substrate region, respectively, and the temperature is controlled by dividing them into four regions, thereby cooling the substrate while maintaining the substrate temperature uniform. In this embodiment, by dividing and cooling the cooling plate in this way, even if the substrate is large and rectangular, the temperature distribution of the substrate becomes uniform within the range of 3.0 ° C. in this embodiment. So that the temperature can be lowered. As a result, the conventional problems such as destruction of elements and wiring on the substrate and the separation of the spacer for maintaining the vacuum withstand voltage from the substrate can be suppressed, and stable cooling can be performed in a short time. Can now.

  The front substrate 11 and the back substrate 12 cooled in the cooling chamber 103 are sent to the getter film deposition chamber 104. In the vapor deposition chamber 104, a barium film is deposited on the outside of the phosphor layer as a getter film. The barium film can prevent the surface from being contaminated with oxygen, carbon, or the like, and can maintain an active state.

  Subsequently, the front substrate 11 and the rear substrate 12 are sent to the assembly chamber 105. In this assembly chamber, the front substrate 11 and the back substrate 12 are arranged to face each other, and the respective substrates are pressurized to sandwich the electrodes 30a and 30b between the sealing layers of both substrates. Thereby, each electrode is in electrical contact with the sealing layers of both substrates simultaneously. In this state, a 140 A direct current is passed through the indium from the power source 120 through the pair of electrodes 30a and 30b in a constant current mode, so that the indium is uniformly melted. Then, by stopping energization, the molten indium is cooled and solidified, and the envelope 10 is formed. The sealed envelope is sent to the cooling chamber 206, cooled to room temperature, and taken out from the unload chamber 207.

  Through the above process, a display device (FED) is completed.

  According to the FED manufacturing method as described above, the cooling plate is divided in accordance with the substrate region, the temperature is controlled for each, and the substrate is set so that the temperature increases as it reaches the peripheral portion of the substrate. The temperature can be lowered while equalizing the temperature. Thereby, since the thermal expansion of the substrate becomes uniform, it is possible to prevent problems such as destruction of elements and wirings on the substrate and separation of the spacer for maintaining the vacuum withstand voltage from the substrate.

  The present invention is not limited to the embodiment described above, and various modifications can be made without departing from the spirit of the present invention. Examples include the following:

  18 and 19 show the configuration of the cooling plate in the third embodiment according to the present invention. The cooling plate 61 shown in FIG. 18 divides the cooling plates 2a and 2b into 9 parts, respectively, as in the first and second embodiments described above, but the area sections are different. In this example, the substrate corner areas 4d, 4d,... Are divided into rectangular areas. The cooling plate 62 shown in FIG. 19 further divides the substrate long side region 4b, the substrate short side region 4c, and the substrate corner region 4d, respectively, and divides each divided region (4b-1, 4b-2, 4c-1, 4c). -2, 4d-1, 4d-2) shows an example in which the temperature can be controlled. Note that the number of divisions and the division structure of the cooling plate can be appropriately optimized depending on the shape and size of the substrate and the characteristics of the cooling device in addition to the above-described configuration. For example, a cooling structure in which the cooling plate is arranged not only on the substrate plane but also on the substrate side surface may be used. Further, as a modification, the cooling plate surface may be cooled while the temperature distribution of the substrate is made uniform by changing the emissivity of the surface of the cooling plate according to the divided regions. For example, the substrate may be cooled by making the temperature distribution of the substrate uniform by forming irregularities, slopes, etc. on the surface of the cooling plate and changing the surface area of the plate stepwise or continuously.

  FIG. 20 shows the configuration of the cooling device in the fourth embodiment of the present invention. Here, a configuration example in which the heating unit and the cooling unit are provided in the same apparatus is shown. In the heat treatment chamber 70, lamp heaters 71, 71,... Are arranged so as to be interposed between the substrates 6 and 7 to be heat treated and the cooling plates 2a, 2b. ,... Are heated by heating the lamp heaters 71, 71,..., And the substrates 6, 7 are cooled by the cooling plates 2a, 2b. As a modification of this embodiment, for example, a sheath heater and a cooling pipe are embedded in the plate, the sheath heater is operated when the substrate is heated, and the cooling is performed by circulating the air through the cooling pipe by weakening the power supply to the sheath heater during cooling. When the temperature is lowered, the substrate may be cooled by stopping the sheath heater and circulating cooling water through the cooling pipe.

  FIG. 21 shows the configuration of the substrate cooling apparatus in the fifth embodiment of the present invention. The substrate cooling device 8 in this embodiment has a configuration in which a plurality of cooling chambers 8a, 8b,. Each of the cooling chambers 8a, 8b,... Is configured as a processing chamber capable of vacuum processing, and is evacuated so that all the chambers are maintained between 1.0 × 10 −5 and 1.0 × 10 −4 Pa. Has been. Each of the cooling chambers 8a, 8b,... Is provided with cooling plates 2a, 2b that are divided into a plurality of regions and controlled as in the first embodiment. Each of the cooling chambers 8a, 8b,... Is connected by a gate valve (not shown) or the like.

  The cooling plates 2a, 2b of each cooling chamber 8a, 8b,... Are maintained at a constant temperature, and the temperature of the cooling plates 2a, 2b provided in each cooling chamber 8a to which the substrate is first transferred is relatively highest, Therefore, the temperature is set so that the temperature of the corresponding cooling plates 2a and 2b becomes lower in the order of the chambers in which they are transferred. The substrate after the heat treatment put into the cooling chamber 8a is cooled while being sequentially transferred to the adjacent cooling chambers 8b, 8c,..., At this time, a cooling plate is provided for each cooling chamber 8a, 8b,. Since the temperature is controlled by dividing the regions 2a and 2b, the substrate temperature is cooled so as to be uniform in the plane. Therefore, also in the present embodiment, it is possible to suppress problems such as destruction of elements and wiring on the substrate that have been generated conventionally.

  In the above-described embodiments, the cooling device that cools the substrate using the cooling plate is taken as an example. However, the cooling means may be configured in a tubular or other shape, for example, instead of the plate shape. The cooling means according to the present invention can also be applied to the case where the inside of the apparatus is not vacuum. Further, examples of the substrate to be applied are not limited to the above-described FED, but can be applied to other display devices such as SED, PDP, and LCD, or semiconductor wafers.

The figure which shows the structure of the principal part of the cooling device in the 1st Embodiment of this invention. The figure which shows the structure of the cooling plate 2a in the said 1st Embodiment. The figure which shows the structure of the cooling plate 2b in the said 1st Embodiment. The figure which shows the internal structure of the 1st area | region of the cooling plate in the said 1st Embodiment. The figure which shows the internal structure of the 2nd-4th area | region of the cooling plate in the said 1st Embodiment. The figure which shows the board | substrate arrangement | positioning state in the cooling device in the said 1st Embodiment. The figure which shows the temperature fall history of the cooling plate in the said 1st Embodiment. The figure which shows the measured value of the substrate temperature in the said 1st Embodiment. The figure which shows the board | substrate arrangement | positioning state in the cooling device in 2nd Embodiment of this invention. The figure which shows the temperature fall history of the cooling plate in the said 2nd Embodiment. The figure which shows the measured value of the substrate temperature in the said 2nd Embodiment. The figure which shows the external appearance structure of FED to which the said 1st Embodiment is applied. The perspective view which shows the internal structure of the said FED. Sectional drawing which shows the internal structure of said FED. The top view which shows the internal structure of the said FED. The perspective view which shows the electrode structure of the said FED. The figure which shows the vacuum processing apparatus provided in the manufacturing process of the said FED. The figure which shows the structure of the cooling plate in the 3rd Embodiment of this invention. The figure which shows the other structure of the cooling plate in the 3rd Embodiment of this invention. The figure which shows the structure of the board | substrate cooling device in the 4th Embodiment of this invention. The figure which shows the structure of the substrate cooling device in the 5th Embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Cooling device, 2a, 2b, 61, 62 ... Cooling plate, 3, 5 ... Cooling pipe, 4 ... Sheath heater, 6, 7 ... Substrate, 8 ... Substrate cooling device, 8a, 8b, ... 8f ... Cooling chamber, DESCRIPTION OF SYMBOLS 10 ... Vacuum envelope, 11 ... Front substrate, 12 ... Back substrate, 13 ... Getter film, 14 ... Support member, 15 ..., 16 ... Phosphor screen, 17 metal back layer, 18 ... Side wall, 19 ... Low melting glass 20 ... black light absorbing layer, 21 ... sealing layer, 22 ... electron-emitting device, 24 ... conductive cathode layer, 25 ... cavity, 26 ... silicon dioxide film, 28 ... gate electrode, 30a, 30b ... electrode, 41, 51 ... first region (substrate central region), 42,52 ... second region (substrate long side region), 43,53 ... third region (substrate short side region), 44,54 ... fourth region (substrate corner region) ), 70 ... Heat treatment chamber, 71 ... Lamp heater DESCRIPTION OF SYMBOLS 100 ... Vacuum processing apparatus 101 ... Load chamber 102 ... Baking, electron beam washing chamber 103 ... Cooling chamber 104 ... Getter film deposition chamber 105 ... Assembly chamber 106 ... Cooling chamber 107 ... Unload chamber 120 ... Power supply, 121 ... Computer.

Claims (37)

In the substrate cooling method of cooling the heat-treated substrate to a predetermined temperature by a cooling means,
The said cooling means cools the said board | substrate according to the temperature conditions set for every some area | region of the said board | substrate, The cooling method of the board | substrate characterized by the above-mentioned. The substrate cooling method according to claim 1, wherein the cooling means cools the substrate in a vacuum. The cooling means includes a plurality of temperature control means corresponding to the areas, and the plurality of temperature control means cools the substrate according to temperature conditions set for each corresponding area. 3. The method for cooling a substrate according to 1 or 2. The cooling means cools the temperature of the entire substrate based on a temperature condition in which the cooling temperature for the corner region of the substrate is set higher than the cooling temperature for the central region of the substrate. The method for cooling a substrate according to claim 3. 5. The substrate cooling method according to claim 3, wherein the cooling means is constituted by a cooling plate provided so as to face a plate surface of the substrate to be cooled, and the temperature control means is provided on the cooling plate. . 6. The substrate cooling method according to claim 5, wherein the cooling plate is subjected to a surface treatment for increasing the emissivity, and the temperature condition is set by changing the emissivity. 6. The temperature control means corresponding to a corner area of the substrate and the temperature control means corresponding to a central area of the substrate among the plurality of temperature control means respectively have different cooling structures. The cooling method of the board | substrate of description. The substrate cooling method according to claim 5, wherein the temperature condition is set by providing irregularities or slopes on a surface of the cooling plate. 9. The substrate according to claim 1, wherein a plurality of the cooling means are arranged along the transfer path of the substrate, and the substrate is cooled by each of the cooling means while moving the transfer path. Cooling method. The cooling means is provided in each of a plurality of chambers connected to each other, and the substrate is cooled by the cooling means provided in the chambers while being moved in the chambers. The method for cooling a substrate as described in 1. In the process of manufacturing a flat rectangular vacuum envelope by joining the peripheral portions of the front substrate and the rear substrate via side walls,
A heating step of heat-treating each of the substrates;
A method for manufacturing a vacuum envelope, comprising: a cooling step of lowering the temperature of the heat-treated substrate to a predetermined temperature while equalizing the temperature of the entire substrate. 12. The vacuum envelope according to claim 11, wherein the cooling step cools the entire substrate according to a temperature condition in which a cooling temperature for the corner region of the substrate is set higher than a cooling temperature for the central region of the substrate. Manufacturing method. The method of manufacturing a vacuum envelope according to claim 12, wherein in the cooling step, the substrates are individually cooled. The method of manufacturing a vacuum envelope according to claim 12, wherein the cooling step cools the substrates simultaneously. The vacuum envelope according to claim 11, wherein a display element is built in the vacuum envelope, and the front substrate serves as a display surface of a display device that displays an image generated by driving the display element. Method. The method of manufacturing a vacuum envelope according to claim 11, wherein the cooling step cools the substrate by a cooling plate provided in a cooling chamber. The cooling plate equalizes the temperature of the entire substrate according to a temperature condition in which the cooling temperature of the plate surface corresponding to the corner region of the substrate is set higher than the cooling temperature of the plate surface corresponding to the central region of the substrate. The method of manufacturing a vacuum envelope according to claim 16, wherein the temperature is lowered. 18. The method of manufacturing a vacuum envelope according to claim 16, wherein in the cooling step, the temperature of the entire substrate is lowered while the temperature of the entire substrate is equalized by a pair of cooling plates provided in the cooling chamber. 19. The vacuum envelope manufacturing method according to claim 16, wherein the cooling plate lowers the temperature of the entire substrate while equalizing the temperature of the plurality of regions of the substrate according to a temperature condition set for each region. Method. The cooling plate has a plurality of temperature control means corresponding to the areas, and the temperature control means lowers the temperature of the substrate while temperature-uniforming according to the temperature condition set for each corresponding area. The method of manufacturing a vacuum envelope according to claim 19. Among the plurality of temperature control means, the temperature control means corresponding to the central region of the substrate is formed with a cooling medium flow path, and the temperature control means corresponding to the corner region of the substrate is supplied with the flow of the cooling medium. 21. The method of manufacturing a vacuum envelope according to claim 20, wherein a path and a heating path are formed, and the plurality of temperature control means lower the temperature of the substrate while equalizing the temperature of the substrate according to a temperature condition set for each corresponding region. . In a substrate cooling apparatus for cooling a heat-treated substrate to a predetermined temperature by a cooling means,
A substrate cooling apparatus comprising cooling means for cooling the heat-treated substrate according to a temperature condition set for each of a plurality of regions of the substrate. The substrate cooling apparatus according to claim 1, wherein the cooling unit cools the substrate in a vacuum. 23. The cooling device according to claim 22, wherein the cooling is performed while the temperature of the entire substrate is equalized according to a temperature condition in which a cooling temperature for the corner region of the substrate is set higher than a cooling temperature for the central region of the substrate. Or the substrate cooling device of 23. The cooling unit includes a plurality of temperature control units corresponding to each region, and the plurality of temperature control units cool the substrate according to a temperature condition set for each corresponding region. The substrate cooling apparatus according to any one of 22 to 24. 26. The substrate cooling apparatus according to claim 25, wherein the cooling means is constituted by a cooling plate provided so as to face a plate surface of the substrate to be cooled, and the temperature control means is provided on the cooling plate. 27. The substrate cooling apparatus according to claim 26, wherein among the plurality of temperature control means, the temperature control means corresponding to the corner area of the substrate and the temperature control means corresponding to the central area of the substrate have different cooling structures. 27. The substrate cooling apparatus according to claim 26, wherein the cooling plate is subjected to a surface treatment for increasing a radiation rate, and the temperature condition is set by changing the radiation rate. 27. The substrate cooling according to claim 22, wherein a plurality of the cooling means are provided along a transfer path of the substrate, and the substrate is cooled by each of the cooling means while moving the transfer path. apparatus. 27. The cooling unit according to any one of claims 22 to 26, wherein the cooling unit is provided in each of a plurality of chambers connected to each other, and the substrate is cooled by the cooling unit provided in the chambers while being moved in the chambers. The board | substrate cooling device of description. In an apparatus for manufacturing a flat rectangular vacuum envelope by joining peripheral portions of a front substrate and a rear substrate via side walls,
Heat treatment means for heating each of the substrates to a preset temperature;
An apparatus for manufacturing a vacuum envelope, comprising: cooling processing means for lowering the temperature of the heat-treated substrate to a predetermined temperature while equalizing the temperature of the entire substrate. 32. The vacuum envelope according to claim 31, wherein a display element is built in the vacuum envelope, and the front substrate constitutes a display surface of a display device that displays an image generated by driving the display element. manufacturing device. 32. The cooling processing means cools the substrate while equalizing the temperature of each region according to a temperature condition in which a cooling temperature for a corner region of the substrate is set higher than a cooling temperature for a central region of the substrate. Vacuum envelope manufacturing equipment. 32. The apparatus for manufacturing a vacuum envelope according to claim 31, wherein the cooling processing means includes a vacuum cooling chamber and a cooling plate provided in the vacuum cooling chamber. 35. The apparatus for manufacturing a vacuum envelope according to claim 34, wherein the vacuum cooling chamber is provided with a plurality of cooling plates, and each cooling plate cools down while the temperature of the substrate is equalized. The cooling plate is divided into a plurality of regions corresponding to the surface to be cooled of the substrate, temperature control means is provided for each of the divided regions, and the temperature control means of each region is set for each region 36. The apparatus for manufacturing a vacuum envelope according to claim 34 or 35, wherein the temperature is lowered while the temperature of the substrate is equalized according to a set temperature condition. Among the plurality of temperature control means, the temperature control means provided corresponding to the central region of the substrate is provided with a cooling medium flow path, and the temperature control provided corresponding to the corner region of the substrate. 37. The apparatus for manufacturing a vacuum envelope according to claim 36, wherein the means is provided with a cooling medium flow path and a heating path.

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