JP6185339B2 - Cooling device, method of manufacturing workpiece using the same, and method of manufacturing processed element - Google Patents

Description

  The present invention relates to a cooling apparatus for efficiently cooling an object to be cooled such as a substrate that requires cooling while maintaining quality, a method for manufacturing a workpiece using the same, and a method for manufacturing a processing element.

  There may be a step of heating the substrate to a high temperature when manufacturing an electronic component or the like. When the substrate heated to a high temperature is rapidly cooled, the properties may be altered or cracks may occur. For example, in the case of a CIGS (Cu—In—Ge—Se) -based compound semiconductor solar cell, a CIGS film is formed on a substrate at a high temperature in order to obtain high light absorption characteristics. Is desorbed, resulting in insufficient formation of a pn junction, and as a result, there is a problem that the photoelectric conversion performance is lowered. Similarly, there is a problem that cracks occur in the substrate during cooling and the yield decreases.

  Therefore, as shown in Patent Document 1, the cooling rate is controlled, or as shown in Patent Document 2, an accommodation region is provided in the substrate transport route following the heating section outlet of the continuous furnace, and passes through this space. Or slowly cooled.

JP 2012-15314 A JP 2011-78963 A

  However, in the techniques described in Patent Document 1 and Patent Document 2, since a cooling unit for cooling is provided in the continuous furnace to be heated, there is a possibility that the tact time is prolonged and the productivity is lowered. Further, even if the techniques described in Patent Document 1 and Patent Document 2 are used, there is a possibility that cracks may occur in the substrate.

  The present invention has been conceived under the circumstances described above, and it is an object of the present invention to provide a cooling apparatus for an object to be cooled that has high productivity and yield. Similarly, it is providing the manufacturing method of the workpiece and the manufacturing method of a processing element which used this cooling device.

In one embodiment of the cooling device of the present invention, a plurality of plate-like objects to be cooled are arranged and held horizontally in a state of being vertically spaced apart from each other in the internal storage area, A housing having a first opening provided above and a second opening provided below, wherein the cooling medium can be moved between the first opening and the second opening by an upward air flow. And a heat storage body arranged at a position higher than the second opening just below the housing area of the housing.

Moreover, in one Embodiment of the manufacturing method of the workpiece of this invention, it is a manufacturing method which manufactures a workpiece by cooling a to-be-cooled object, Comprising: A housing | casing area | region inside, The 1st provided above the said housing | casing area | region A housing having an opening and a second opening provided below, wherein a cooling medium can be moved between the first opening and the second opening by an upward air flow, and the housing A plurality of plate-like objects to be cooled are vertically set apart from each other in the housing region of the cooling device having a heat storage body disposed immediately below the housing region and higher than the second opening. A holding step of horizontally arranging and holding in a state where the cooling medium is placed, and the cooling medium flows into the cooling device from the second opening, and the cooling medium flows out of the cooling device from the first opening. And a cooling medium moving step.

  Moreover, one embodiment of the manufacturing method of the processing element of the present invention is a direction in which the workpiece manufactured by the above-described manufacturing method of the workpiece is taken out of the cooling device and located at the same height in the cooling device. A dividing step of dividing the workpiece into a plurality of processing elements.

  ADVANTAGE OF THE INVENTION According to this invention, the cooling device of the to-be-cooled object which has high productivity and a high yield can be provided.

(A), (b) is the perspective view and sectional drawing which respectively show schematic structure of the cooling device which concerns on one embodiment of this invention. (A), (b) is the typical top view which shows the temperature distribution in the to-be-cooled object in the case of cooling in the conventional method, respectively, and the temperature in the to-be-cooled object in the case of cooling using the cooling device shown in FIG. It is a typical top view showing distribution.

  An example of an embodiment of a cooling device and a workpiece manufacturing method and a processing element manufacturing method using the cooling device of the present invention will be described with reference to the drawings.

(Cooling system)
Fig.1 (a) is a typical perspective view which shows the example of the cooling device 1 which concerns on one of embodiment of this invention. FIG.1 (b) is sectional drawing in the Ia-Ia line | wire of Fig.1 (a).

  The cooling device 1 includes a housing 10 and a heat storage body 20. The material of the housing 10 is not particularly limited as long as the housing 10 has high heat resistance and has a strength capable of holding the object to be cooled 50 accommodated therein. For example, a metal such as stainless steel, a ceramic, or the like is exemplified. Can do.

  The housing 10 has a frame shape, and the side wall 11 is formed so as to form a closed space when viewed from above. The upper side (D1 direction in the figure) and the lower side (D2 direction in the figure) of the side wall 11 are opened. The housing 10 is thus hollow, and has a storage area 12 in a space surrounded by the side walls 11.

  A plurality of plate-like objects to be cooled 50 are accommodated in the accommodation region 12. The plurality of objects to be cooled 50 are arranged at regular intervals in the thickness direction. In other words, the objects to be cooled 50 are erected vertically and arranged in the horizontal direction.

  The housing 10 has a first opening 13 and a second opening 14. The cooling medium is movable from the first opening 13 to the second opening 14 through the accommodating region 12. In other words, the cooling medium that has flowed into the housing 10 from the second opening 14 passes through the storage region 12 and is discharged from the first opening 13.

The first opening 13 is located above the accommodation region 12, and in this example, the open end above the side wall 11 functions as the first opening 13. The 2nd opening part 14 is located under the accommodating area | region 12, and is formed in the side surface (side wall 11) of the housing | casing 10 in this example. There may be one second opening 14 or a plurality of second openings 14. In addition, the second opening 14 is formed on the side surface of the housing 10, so that the cooling medium can be guided into the accommodation region 12 even when the cooling device 1 is installed on the floor surface or the like.

  The heat storage body 20 has a higher heat capacity than the object to be cooled 50. For example, the volume may be increased by using the same material as the housing 10 and increasing the thickness compared to the thickness of the side wall 11 constituting the housing 10. Moreover, you may form using the material which has a high specific heat. Examples of such a high specific heat material include ceramics and graphite.

  Such a heat storage body 20 is disposed below the accommodation region 12 of the housing 10. In this example, it is disposed between the second opening 14 and the accommodation region 12. Thus, when arrange | positioning the thermal storage body 20 in the accommodation area | region 12 side rather than the 2nd opening part 14, it arrange | positions at intervals with the housing | casing 10 so that a cooling medium can move, or thermal storage. What is necessary is just to provide the heat exchange path 21 which connects the 2nd opening part 14 and the accommodation area | region 12 in the body 20. FIG. Alternatively, a plurality of heat storage bodies 20 may be provided and arranged in the horizontal direction with a space between each other, whereby the gap between the heat storage bodies 20 may function as a flow path through which the cooling medium can move. The position where the heat exchange path 21 and the gap are provided is not particularly limited as long as the cooling medium is supplied to each of the plurality of objects 50 to be cooled. It may be provided.

  The heat storage body 20 may be supported by being joined to the housing 10 directly or via a jig. In this case, for example, it may be formed integrally with the housing 10. Further, it may be placed and held on a holder provided in the housing 10. In this case, for example, a holder made of mesh-like graphite, punched stainless steel, or the like may be attached to the housing 10 and placed.

  Here, the cooling medium is not particularly limited as long as it is a gas capable of cooling the object to be cooled 50. For example, it can be the same as the atmosphere in which the cooling device 1 is disposed. Examples of such an atmosphere include air, inert gas, oxygen, and the like.

  The cooling device 1 having the above-described configuration can cool the object to be cooled 50 with high productivity and without deterioration in quality. Hereinafter, the reason will be described in detail.

  Conventionally, when the plate-shaped object 50 is cooled, as shown in FIG. 2A, cooling is performed in order from the outer peripheral portion in contact with the cooling medium, and the high temperature portion remains in the central portion. In other words, the temperature distribution was such that the high temperature part was surrounded by the low temperature part. For this reason, there has been a problem that cracks and the like are generated without being released (disallowed to be displaced) due to thermal expansion / shrinkage due to temperature distribution.

  On the other hand, according to the cooling device 1, the cooling medium flowing in from the second opening 14 cools the second opening 14 side (D2 direction side) of the object 50 to be cooled, and then the high-temperature covered object. It is warmed by the cooling object 50, becomes an ascending current, and becomes a one-way flow toward the first opening 13. For this reason, as shown in FIG.2 (b), the temperature distribution in the to-be-cooled object 50 has a gradient in one direction toward the 1st opening part 13 side from the 2nd opening part 14 side. By cooling while forming such a temperature distribution, distortion of thermal expansion / shrinkage can be released without suppressing deformation of the object to be cooled 50, and as a result, generation of cracks, cracks, etc. is suppressed. can do.

  In particular, since the cooling device 1 includes the heat storage body 20, the heat flow from the heat storage body 20 can accelerate the air flow toward the first opening 13. Thereby, the surrounding atmosphere medium flows in from the 1st opening part 13 side, the 1st opening part 13 side of the to-be-cooled object 50 is cooled, and it can suppress that a downward flow generate | occur | produces in an atmosphere medium. In other words, the turbulence of the flow of the cooling medium on the first opening 13 side of the housing region 12 can be suppressed, and the unidirectional flow from the second opening 14 to the first opening 13 can be maintained.

  As a result, the first opening 13 side of the object to be cooled 50 always has the highest temperature in the cooling device 1, and the temperature distribution shown in FIG. 2 (b) can be realized, and the object to be cooled is not degraded. The object 50 can be cooled.

  As described above, the cooling medium circulation system and the fan that use the electric power or the like by the first opening 13, the second opening 14, and the heat storage body 20 as well as the desired arrangement of the object 50 to be cooled by the casing 10. The cooling medium can be passed through the containing region 12 in a unidirectional flow without using the above. For this reason, the cooling device 1 can cool the cooled object 50 with high productivity.

  Further, conventionally, the temperature of the atmosphere around the object to be cooled 50 has been gradually lowered in a slow cooling chamber made continuous from the heating furnace. For this reason, the tact time is increased and the apparatus is large. On the other hand, the cooling device 1 can gradually cool the object to be cooled 50 by the heat storage body 20. That is, it can be taken out immediately from the heating furnace, and a large-scale apparatus is not required. For this reason, the cooling device 1 can cool the object 50 to be cooled while maintaining high productivity.

  Furthermore, in this embodiment, the cooling device 1 is composed only of a material having high heat resistance such as a metal such as stainless steel or ceramics. That is, the cooling device 1 is configured without including a low melting point material such as an organic material or an adhesive. In this case, the cooling device 1 can also be used as a rack for accommodating and transporting the object to be cooled 50. In other words, a function as a rack when the substrate-like object to be cooled 50 is led into the furnace and heated, and a function as a cooling device for taking out and gradually cooling without setting a special cooling process from the heating furnace. This can be realized with one structure.

  Further, in this example, the heat storage body 20 is located between the second opening 14 and the accommodation region 12. That is, the cooling medium is introduced into the accommodation region 12 after contacting the heat storage body 20. In this case, if a volatile active ingredient is applied to the heat storage body 20, it can be processed simultaneously with slow cooling.

  In addition, as the to-be-cooled object 50, a liquid crystal, CIGS, etc. containing materials, such as an electronic component with which a thin film is formed on a board | substrate, or the material from which a thermal expansion coefficient differs, and glass with a large thermal expansion coefficient are included. Examples of such a compound-based thin film solar cell element.

  In particular, when cooling a CIGS solar cell, the generation of cracks in the power generation layer due to the difference in the thermal expansion coefficient between the substrate and the power generation layer is suppressed in the slow cooling step after application and heating of the CiGS film serving as the power generation layer. be able to. Moreover, when the sealing structure by a cover glass is provided, it can suppress that this cover glass cracks in a cooling process.

(Modification)
In the above example, the lower portion of the housing 10 is open, but the lower portion may be closed as long as the second opening 14 is provided. The first opening 13 is an open portion above the housing 10, but the upper surface may be closed and formed on the side wall 11, a lid may be formed on the upper surface, and a hole may be formed in the lid. May be formed. However, the first opening 13 has a larger area than the second opening 14 so that the cooling medium can be discharged from the first opening 13 without disturbing the flow of the cooling medium above the accommodation region 12. Is preferred.

In addition, a lid connected to the upper end of the side wall 11 is formed, and contact with the atmosphere having a low temperature is suppressed from the first opening 13 side. A plurality may be provided. In this case, the discharge speed of the cooling medium can be increased by increasing the resistance of the cooling medium and increasing the pressure above the accommodation area 12. Thereby, the one-way | direction flow of the cooling medium from the 2nd opening part 14 to the exterior of the 1st opening part 13 can be ensured.

  Further, the shape of the housing 10 in a top view is not limited to a rectangular shape. For example, it may be circular and the objects to be cooled 50 may be arranged radially.

  The plurality of objects to be cooled 50 may not be held at the same height position.

  Furthermore, in the above-described example, the cross-sectional shapes at the same height position of the housing 10 are the same, but may be different. For example, the cross-sectional area may be gradually reduced from the lower side (D2 direction) to the upper side (D1 direction).

  In this case, even if the buoyancy (upward propulsive force) decreases by moving away from the heat storage body 20 as it goes upward, the flow velocity going upward can be maintained by narrowing the flow path of the cooling medium. is there. By adopting such a configuration, it is possible to suppress the generation of a vortex in the flow of the cooling medium in the upper direction and maintain the flow in one direction.

(Manufacturing method of workpiece, manufacturing method of processing element)
<Holding process>
A plurality of plate-like objects 50 to be cooled are held in the cooling device 1 in a state where they are vertically spaced apart from each other. Here, the term “vertical” does not mean strictly 90 °, but a deviation of about ± 10 ° is allowed.

  The object to be cooled 50 can be held using a suspension jig (not shown), or can be arranged and held by a guide rail or the like provided in the housing 10.

  Here, the heat storage body 20 is heated to a high temperature. Specifically, it is preferable that the temperature is equal to or lower than the temperature of the object to be cooled 50 before cooling. The heat storage body 20 may be heated at the same time as the object to be cooled 50 is heated, or may be heated in a separate process. As an example of the former, by using the cooling device 1 as a rack and arranging it in a heating atmosphere such as a heating furnace at the same time as a heating process for heating the object to be cooled 50, the heat accumulator 20 is mounted together with the heating process of the object to be cooled. It can be heated to a high temperature. This process will be described later.

  Such a cooling device 1 is placed in an atmosphere having a temperature lower than the temperature of the object to be cooled 50 before cooling.

<Cooling medium transfer process>
Next, the cooling medium is caused to flow into the cooling device 1 from the second opening 14, and the cooling medium is caused to flow out of the cooling device 1 from the first opening 13. The flow of the cooling medium can be automatically generated by the configuration of the cooling device 1 in which the first opening portion 13 is positioned above and the heat storage body 20 is disposed below the accommodation region 12. In other words, the 1st opening part 13, the 2nd opening part 14, and the heat storage body 20 form the automatic cooling medium moving pump which does not require external force and energy. In other words, it is possible to automatically suck and discharge the cooling medium.

  The cooling medium is not particularly limited as long as it is a gas lower than the temperature of the object to be cooled 50 before cooling. For example, the gas which comprises the atmosphere which arrange | positions the cooling device 1 can be used. In this example, air is used as a cooling medium by disposing it in the atmosphere.

The temperature of the cooling medium flowing in from the second opening 14 may be constant or may vary. In this example, since the cooling device 1 is arranged in an atmosphere at room temperature, it is not intentionally changed from room temperature. However, the temperature of the cooling medium flowing into the cooling device 1 may be controlled to gradually decrease. This is because it can be gradually cooled under milder conditions. Such temperature control of the cooling medium may be performed by controlling the temperature of the atmosphere in which the cooling device 1 is disposed.

  And the to-be-cooled object 50 is cooled to desired temperature, and a workpiece is obtained.

<Division process>
A dividing step may be provided following the cooling medium moving step. In this case, after cooling the object to be cooled 50 to a desired temperature, the object to be cooled 50 is taken out from the cooling device 1. And a workpiece is divided | segmented along the direction located in the same height in the cooling device 1, and a working element is obtained. For the division, a normal dicing process or the like can be used.

  By dividing | segmenting in such a direction, it can divide | segment along the direction of the temperature gradient produced in the to-be-cooled object 50 at the time of cooling (refer FIG.2 (b)). Therefore, it is possible to reduce the stress distribution due to strain or the like in the dividing element. In addition, when there is a difference in the characteristics of the object to be cooled 50 depending on the cooling rate, the processed object 50 has uniform characteristics in the processing element. Examples of the difference in the characteristics of the object to be cooled 50 depending on the cooling rate include crystallinity and composition of components.

  As described above, it is possible to provide a high-quality processing element having a small characteristic distribution including a stress distribution in each divided processing element.

(Further modification of the cooling device 1)
In the cooling device 1, the upper portion of the accommodation region 12 may be heated. As the heating method, heating by a heater or the like, or heating by arranging a heating body equivalent to the heat storage body 20 can be adopted. In this way, by increasing the temperature above the storage area 12, the unidirectional flow of the cooling medium is maintained without cooling the end of the object 50 to be cooled located above the storage area 12. Can do. Furthermore, by raising the temperature above the accommodation area 12 and positively discharging the cooling medium to the outside of the cooling device 1, the upper area of the accommodation area 12 is quasi-depressurized. For this reason, a cooling medium can be attracted | sucked upwards of the storage area | region 12 more reliably, and a one-way flow of a cooling medium can be maintained.

  Heat may be preliminarily heated inside or outside the side wall 11 so that the temperature inside the cooling device 1 forms a desired temperature gradient. As the heating method, heating by a heater or the like, or heating by arranging a heating body equivalent to the heat storage body 20 can be adopted.

  Further, a fan may be installed below the accommodation area 12 to assist the movement of the cooling medium.

(Modification 1 of the manufacturing method of a workpiece)
A scribing process may be provided following the cooling medium moving process. In this case, after cooling the object to be cooled 50 to a desired temperature, the object to be cooled 50 is taken out from the cooling device 1. Then, the workpiece is scribed along a direction located at the same height in the cooling device 1. For example, when a thin film is laminated on a substrate, it may be processed so that only this thin film is divided.

  By scribing in such a direction, the thin film can be divided along the direction of the temperature gradient generated in the object to be cooled 50 during cooling (see FIG. 2B). As described above, the stress distribution can be reduced in each divided thin film.

(Modification 2 of the manufacturing method of a workpiece)
In the holding step, a heating step may be provided after holding the object to be cooled 50 in the cooling device 1. In this case, at the stage of holding the object to be cooled 50, neither the object to be cooled 50 nor the heat storage body 20 is heated, for example, at room temperature. Thereafter, the cooling device 1 is heated together with the cooled object 1 held in the cooling device 1. For example, the cooling device 1 is used as a rack and put into a heating furnace. Thereby, the thermal storage body 20 is heated to the substantially same temperature with the to-be-cooled object 50.

  Next, in the cooling medium moving step, the heated cooling device 1 is installed at a temperature lower than the temperature in the heating step. As a result, the cooling medium automatically moves.

  With such a configuration, the cooling device 1 can be used as a rack, and the heating of the heat storage body 20 can be performed simultaneously with the heating process of the object to be cooled 50, so that productivity can be improved. .

DESCRIPTION OF SYMBOLS 1 ... Cooling device 10 ... Housing | casing 11 ... Side wall 12 ... Storage area 13 ... 1st opening part 14 ... 2nd opening part 20 ... Heat storage body 50 ... Covered Cooling object

Claims (6)

A plurality of plate-like objects to be cooled are horizontally arranged and held in an internal storage area in a state of being vertically spaced apart from each other, and a first opening provided above the storage area; A housing having a second opening provided below, and a cooling medium movable between the first opening and the second opening by a rising airflow ;
A heat storage body arranged at a position higher than the second opening just below the housing area of the housing;
A cooling device comprising: The casing is a hollow cylinder,
The first opening is provided so as to open above the accommodation area,
The cooling device according to claim 1, wherein the second opening is provided on a side surface of the housing.   The heat storage body is disposed between the accommodation area and the second opening, and has a heat exchange path through which the cooling medium can pass and connects the second opening and the accommodation area. Item 3. The cooling device according to Item 1 or 2.   The cooling device according to any one of claims 1 to 3, wherein the heat storage body is a metal. A manufacturing method for manufacturing a workpiece by cooling an object to be cooled,
It has a housing area inside, a first opening provided above the housing area and a second opening provided below, and a cooling medium is provided between the first opening and the second opening. In the housing region of the cooling device, including a housing that can be moved by an updraft, and a heat storage body that is disposed directly below the housing region of the housing and at a position higher than the second opening. A holding step of holding the plate-like objects to be cooled spaced apart from each other and arranged horizontally in a vertically standing state;
A cooling medium moving step of causing the cooling medium to flow into the cooling device from the second opening and causing the cooling medium to flow out of the cooling device from the first opening. Method.   The workpiece manufactured by the method for manufacturing a workpiece according to claim 5 is taken out from the cooling device and divided along a direction located at the same height in the cooling device to divide the workpiece into a plurality of workpieces. The manufacturing method of a processing element which has the division | segmentation process used as a processing element.

Images