Heating and cooling device

Abstract

Heating and cooling device (102), comprising: an airtight processing chamber (4) which has an opening / closing system (8) which is capable of loading and unloading an element (1) to be processed; an induction heating device (2) which contains one or more induction heating coils (2a) by which the element (1) to be processed is heated; a cooling device (3) that cools the element (1) to be processed; a temperature sensor (5) for determining the temperature of the element (1) to be processed; and and a control device (6) that controls the induction heating device (2) and the cooling device (3) on the basis of the temperature determined by the temperature sensor (5); wherein a displacement device (15) is arranged such that the element to be processed (1) and / or a cooling unit of the cooling device (3) are displaced in order to change a distance between the element to be processed (1) and the cooling unit of the cooling device (3), wherein the heating and cooling device (102) includes: a cooling plate (3f) which is arranged between the element to be processed (1) and the induction heating coil (2a).

Description

TECHNICAL FIELD

[0001] The present invention relates to a heating and cooling device. More specifically, the present invention relates to a heating and cooling device by which a semiconductor element is suitably soldered to a substrate. STATE OF THE ART

[0002] In a conventional soldering system, a continuous-flow reflow oven performs a reflow process while a component to be soldered is placed on a conveyor, passing through a preheating zone, a main heating zone, and a cooling zone. The reflow oven is generally designed to be open to the atmosphere.

[0003] However, recently, a power semiconductor module and the like, for example, used as a switching device used for power conversion purposes, must be able to operate under harsh environmental conditions. Excellent strength and high heat resistance are also required in a solder joint surface between an insulating substrate and a semiconductor chip, such as an insulated-gate bipolar transistor (IGBT) or an electronic component, such as a flywheel diode (FWD), or in another solder joint surface between the insulating substrate and a base plate.Then, instead of a solder material composed of a Sn-Ag based material which does not have sufficient joining strength although it has excellent solder wettability, there is an increasing tendency to use another solder material composed of a Sn-Sb based material with high concentration of Sb, with which excellent joining strength is easily achieved.

[0004] However, compared to the solder material composed of Sn-Ag-based materials, the solder material composed of Sn-Sb-based materials lacks solder wettability properties, resulting in the formation of a thick oxide on the surface of a component to be soldered. When using a reflow oven open to the atmosphere, the surface oxide on the component to be soldered is not completely reduced, resulting in the problem that a defect is easily formed on the solder joint surface.

[0005] Patent Literatures 1 to 3 describe a way to prevent the occurrence of defects by performing a reflow process under a reducing gas atmosphere to improve solder wettability.

[0006] Furthermore, Patent Literature 4 discloses another reflow furnace configured to perform a reflow process on a material to be processed, wherein an interior of a vertical processing tube capable of being hermetically sealed is divided into a main heating zone, a preheating zone, and a cooling zone, and an elevator carrying the material to be processed is moved up and down and stops in each of the preheating zone, the main heating zone, and the cooling zone in accordance with the conditions of the required processing time.

[0007] On the other hand, Patent Literature 5 discloses a soldering apparatus including, in a chamber with an opening / closing system, a heating plate, at least a portion of which a substrate is placed is flat, and including a heater; a cooling plate having a surface capable of being brought into close contact with the heating plate, the cooling plate being provided so as to be displaceable forward and backward relative to the heating plate; and the chamber being connected to a vacuum suction pump, a supply source for supplying carboxylic acid vapor, and another supply source for supplying non-oxidizing gas.

[0008] US 2008 / 0 023 530 A1 discloses a method for manufacturing an electronic component. One embodiment provides two soldering partners to be joined together at a designated joint, at least one of which contains an electronic component or is designed as such, a soldering device with an inductor, and an intermediate plate. The soldering partners, the inductor, and the intermediate plate are arranged such that the intermediate plate is located between the electronic component and the designated joint, on the one hand, and the inductor, on the other. The soldering partners are connected at the designated joint with a solder that is melted by the energy emitted by the inductor. JP 2007-242691 A discloses that, in a joining method for joining an electronic component to a pad arranged on a substrate by solder, excitation heads with coolers to and from fluid flows are used as heating means for heating the solder. The heating means heats the pad and the solder through high-frequency induction heating. The excitation heads are brought into contact with the electronic component after the solder has melted. Cooling water from a cooling water tank is circulated and supplied to the cooler to perform cooling.

[0009] US 2012 / 0 248 094 A1 discloses a soldering method. In this method, at least two sets of components are heated and soldered together. Each set contains a first soldering partner, a second soldering partner, and a solder. During the soldering process, the individual temperatures of each set are transmitted via a radio-frequency transmitter to a receiving and control unit. The control unit controls the heating of the sets depending on the transmitted individual temperatures.

[0010] DE 10 2012 206 403 B3 discloses a soldering system. This system is designed to accommodate a first pair of workpieces and a second pair of workpieces. Each of the workpiece pairs comprises a first workpiece and a second workpiece to be soldered to it using solder. Furthermore, a heating unit is provided, which is designed to provide energy for melting the solder, as well as a first positioning unit and a second positioning unit. A first distance between the first pair of workpieces and the heating unit can be adjusted by means of the first positioning unit. Accordingly, a second distance between the second pair of workpieces and the heating unit can be adjusted by means of the second positioning unit, independently of the first distance. PRINTED LITERATURE DIRECTORYPATENT LITERATURE Patent literature 1: JP 2010 - 161 207 A Patent literature 2: JP 2008 - 182 120 A Patent literature 3: JP 2009 - 170 705 A Patent literature 4: JP 2002 - 144 076 A Patent literature 5: JP H11 - 233 934 A PRESENTATION OF THE INVENTION PROBLEM TO BE SOLVED BY THE INVENTION

[0011] However, the devices disclosed in Patent Literature 1 to 3, respectively, do not include a cooling device. Thus, there is a problem that a long time is required to complete the solidification of the solder, resulting in poor efficiency because cooling after heating depends on natural cooling with respect to the member to be soldered. Furthermore, in the case of a device described in Patent Literature 4, since the respective zones require space for a preheating zone, a main heating zone, and a cooling zone, there is a limitation on the miniaturization of the device.Furthermore, in the case of an apparatus described in Patent Literature 5, since the structure is configured to heat the member to be soldered by contact heat conduction so that the member to be soldered is placed on a hot plate having a heating device such as a sheathed heater, there is a problem that residual heat remaining in the hot plate leads to poor cooling efficiency by the cooling plate even if the power supply to the sheathed heater is cut off.

[0012] In view of these problems, it is an object of the present invention to provide a heating and cooling apparatus capable of performing heating and cooling processes in an airtight processing chamber and capable of realizing the miniaturization of the apparatus in conjunction with an increase in heating and cooling efficiency. MEANS TO SOLVE THE PROBLEM

[0013] To achieve the above-described problem, a heating and cooling device is provided, comprising: an airtight processing chamber having an opening / closing system capable of loading and unloading a member to be processed; an induction heating device containing one or more induction heating coils for heating the member to be processed; a cooling device for cooling the member to be processed; a temperature sensor for detecting a temperature of the member to be processed; and a control device for controlling the induction heating device and the cooling device based on the temperature detected by the temperature sensor.wherein a displacement device is arranged such that the element to be processed and / or a cooling unit of the cooling device are displaced in order to change a distance between the element to be processed and the cooling unit of the cooling device, wherein the heating and cooling device includes: a cooling plate arranged between the element to be processed and the induction heating coil;

[0014] According to the heating and cooling device of the present invention, when the member to be processed arranged inside the airtight chamber is heated or cooled, the heating and cooling device is suitable for performing, for example, a reflow soldering process under a reducing gas atmosphere. Since the heating and cooling device directly heats a component that can be heated by induction heating, the heating process can be performed without being affected by the cooling device even if the cooling device is arranged to be adjacent to or close to the member to be processed. When a temperature increase occurs in the member to be processed, the cooling device is detached from the member to be processed using the displacement device, which reduces the cooling ability. Then, the member to be processed can be heated quickly.Furthermore, when the workpiece is kept at a constant temperature, the cooling device is brought closer to the workpiece using the displacement device, balancing heating and cooling. Thus, the temperature of the workpiece can be controlled with greater precision. Furthermore, when a temperature reduction is performed in the workpiece, cooling can be performed quickly, so that the cooling device is brought closer to the workpiece using the displacement device.In order to increase heating and cooling efficiency and shorten operating time, the above-described processes involving heating and cooling steps can be performed in such a way that the heating and cooling steps are performed continuously without horizontally displacing the workpiece in the chamber. Furthermore, the heating and cooling device can be miniaturized.

[0015] In the heating and cooling device according to the present invention, the induction heating coil is preferably arranged at a lower position than the member to be machined, and the cooling unit is preferably configured to form a one-piece construction with a cooling system and the induction heating coil.

[0016] The cooling unit of the cooling device for cooling the workpiece is configured to form a one-piece construction with the cooling system and the induction heating coil. This saves the space in the chamber where the workpiece is stored, allowing for miniaturization of the chamber.

[0017] In the heating and cooling device according to the present invention, the cooling system in which the induction heating coil has a hollow structure is preferably configured to form a flow path through which a coolant can circulate.

[0018] According to one aspect described above, the induction heating coil with the hollow structure allows the coolant to circulate through the flow path. For example, when cooling water is circulated in the hollow structure, the workpiece and the induction heating coil can be efficiently cooled.

[0019] In the heating and cooling device according to the present invention, the cooling unit preferably includes the cooling plate which abuts against the upper surface of the induction heating coil having the hollow structure during the cooling operation.

[0020] According to another aspect described above, when a temperature increase is performed in the member to be machined, the cooling plate is detached from the member to be machined using the displacement device, and then the member to be machined can be heated by the induction heating coil. Furthermore, when a temperature decrease is performed in the member to be machined, the member to be machined can be cooled quickly because the cooling plate rests against the member to be machined using the displacement device.

[0021] The heating and cooling device according to the present invention preferably includes: another flow path through which a coolant other than the cooling system circulates and which is arranged at a lower position than the cooling plate, wherein the induction heating coil is immersed in the coolant.

[0022] According to the further aspect described above, the circulation of the coolant in the flow path leads to cooling of the cooling plate. Thus, the element to be machined can be cooled by the cooling plate cooled during cooling.

[0023] In the heating and cooling device according to the present invention, the cooling plate is preferably formed of ceramics such as silicon carbide, silicon nitride or aluminum nitride.

[0024] According to another aspect described above, the workpiece can be heated even when the induction heating coil is arranged below the cooling plate. Furthermore, rapid cooling can be achieved through heat exchange with the cooling plate when the workpiece, which has been heated, comes into contact with the cooling plate. This can reduce unnecessary energy losses due to heating and cooling.

[0025] In the heating and cooling device according to the present invention, an insulating cover formed of a heat-resistant insulating material is preferably arranged to cover a surface of the induction heating coil.

[0026] According to another aspect described above, the insulating cover composed of a heat-resistant insulating material such as ceramic, poly(tetrafluoroethylene) resin, or the like covers the surface to prevent exposure of the induction heating coil, thereby preventing the induction heating coil from short-circuiting due to conductive dust particles or foreign matter deposited on the induction heating coil when the workpiece is heated. This can prevent discharge from occurring between conductive components. The heating and cooling device can then be operated safely for an extended period of time without performing maintenance.

[0027] In the heating and cooling device according to the present invention, the cooling unit is preferably arranged at a lower position than the member to be processed, and the induction heating coil is preferably provided at a higher position than the member to be processed.

[0028] According to another aspect described above, even when the distance between the workpiece and the induction heating coil becomes small, even though they are not in contact with each other, the workpiece can be efficiently heated. Furthermore, since there are no obstacles such as a cooling plate between the workpiece and the induction heating coil, the heating efficiency can be increased.

[0029] In the heating and cooling device according to the present invention, the cooling unit may be arranged at a lower position than the member to be processed, and the induction heating coil may preferably be provided at a different lower position than the member to be processed.

[0030] According to the structure described above, even when workpieces of different heights are continuously machined, height adjustment of the distance between the workpiece and the induction heating coil can be eliminated. This can lead to improved workflow.

[0031] In the heating and cooling device according to the present invention, the control means preferably controls the induction heating means and the cooling means based on the temperature detected by the temperature sensor electromagnetically shielded from the induction heating coil, using the parameters: a wave number and a supply current applied to the induction heating means; a flow rate and another temperature of a coolant supplied to the cooling means at an inlet; and a distance between the member to be processed and the cooling plate.

[0032] According to another aspect described above, the control device can precisely control parameters related to heating and cooling based on electrical signals, resulting in control of the induction heating device and the cooling device. Furthermore, the temperature sensor is arranged such that it is electromagnetically shielded from the induction heating coil and can thus precisely determine the temperature of the element to be processed.

[0033] The heating and cooling device according to the present invention preferably includes: an evacuation device connected to the processing chamber; a reducing gas supply device for supplying a reducing gas into the processing chamber; an inert gas supply device for supplying an inert gas into the processing chamber; wherein the control device preferably controls the evacuation device, the reducing gas supply device, and the inert gas supply device.

[0034] According to another aspect described above, after the processing chamber has been evacuated, the control device allows the reducing gas supply device to introduce the reducing gas into the processing chamber by controlling the evacuation device. A reduction reaction can then be carried out on the surface of the member to be processed. Furthermore, the control device allows the inert gas supply device to introduce the inert gas into the chamber, so that the inert gas can replace the reducing gas. As a result, the chamber can be safely opened to the atmosphere.

[0035] The heating and cooling device according to the present invention preferably includes a pressure gauge for detecting the internal pressure of the processing chamber, wherein the control means controls the evacuation means so as to reduce the pressure of the processing chamber and then obtains the internal pressure of the processing chamber detected by the pressure gauge, so that the control means generates an output signal so as to convert the internal pressure into the maximum applied current based on parameters related to the wave number and the current applied to the induction heating means.

[0036] According to another aspect described above, the control device is configured to obtain the internal pressure of the processing chamber, which is in a negative pressure state, using, for example, the pressure gauge, and perform a calculation that takes into account the internal pressure and the heating position of the member to be processed, so that the maximum allowable applied current is immediately output to the induction heating coil in a region where no discharge occurs in the chamber. This enables the control device to heat the member to be processed even when the chamber is controlled to a negative pressure. For example, when solder material is melted for brazing the member to be processed, a generated gas is easily discharged. This can lead to a reduction in defects and an improvement in brazing quality.

[0037] In the heating and cooling device according to the present invention, the induction heating coil is preferably formed from one or a plurality of coils having a vertically oriented elliptical shape in the longitudinal direction, with a constriction arranged around the center thereof and which are preferably arranged parallel to the element to be processed.

[0038] According to another aspect described above, forming such a coil shape can prevent heat from concentrating near the center position of the tray on which the member to be machined is placed. This can result in excellent uniform temperature distribution in the member to be machined, even if a main surface of the member to be machined has a rectangular shape, for example.

[0039] In the heating and cooling apparatus according to the present invention, preferably two or more groups of the induction heating means and the cooling means are arranged in a processing chamber.

[0040] According to another aspect described above, all parts except the induction heating coil and the cooling unit can be shared. Furthermore, by accommodating twice as many heating and cooling units or more than the conventional unit, twice as many components to be processed can be processed by heating and cooling at once. This can lead to cost reduction and significant throughput improvements.

[0041] The heating and cooling device according to the present invention preferably includes a pressing unit with which a tray is pressed against the cooling unit, wherein the tray on which the element to be processed is placed is cooled when the tray is in contact with the cooling unit.

[0042] According to another aspect described above, when the tray on which the member to be machined is placed is cooled in a state where the tray is in contact with the cooling unit, the pressing unit presses the tray against the cooling unit. This can increase the contact area with which the tray is in contact with the cooling unit, improving the cooling efficiency. IMPACT OF THE INVENTION

[0043] According to the heating and cooling device of the present invention, the member to be processed can be efficiently heated and cooled because the displacement device can displace the member to be processed or the cooling unit of the cooling device or both. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 shows a schematic representation according to an embodiment of a heating and cooling device of the present invention. Fig. 2 shows plan views illustrating examples of induction heating coils used in the heating and cooling device of the present invention. Fig. 3 shows further schematic diagrams corresponding to a gourd-shaped induction heating coil used in the heating and cooling device of the present invention. Fig. 4 shows a further schematic diagram according to another embodiment of the heating and cooling device of the present invention (including an induction heating coil with a hollow structure). Fig. 5 shows a further schematic diagram according to another embodiment of the heating and cooling device of the present invention (including the induction heating coil with the hollow structure and a cooling plate). Fig. Figure 6 shows a further schematic diagram according to another embodiment of the heating and cooling device of the present invention (including a chamber in which two groups can be accommodated). Fig. Figure 7 shows a further schematic diagram according to another embodiment of the heating and cooling device of the present invention (including the induction heating coil arranged in a non-contact manner near the upper surface of the chamber). Fig. Figure 8 shows a further schematic diagram according to another embodiment of the heating and cooling device of the present invention (including the induction heating coil arranged in a further non-contact manner near the lower surface of the chamber). Fig. 9 shows a further schematic diagram according to another embodiment of the heating and cooling device of the present invention (including an induction heating coil arranged in a coolant vessel). Fig. 10 shows a further schematic diagram according to another embodiment of the heating and cooling device of the present invention (including an insulating cover for the induction heating coil). Fig. 11 shows another schematic diagram according to another embodiment of the heating and cooling apparatus of the present invention (including a tray pressing system and a pressure gauge). EMBODIMENTS OF THE INVENTION

[0044] The following is based on reference to Fig. 1 describes an embodiment of a heating and cooling device of the present invention.

[0045] Fig. 1 shows a schematic representation of a heating and cooling device of the present invention.The heating and cooling device 100 includes: an airtight processing chamber 4 having an opening / closing system capable of loading and unloading a member 1 to be processed; a cooling unit 3a of a cooling device 3 arranged at a lower position than the member 1 to be processed; an induction heating coil 2a of an induction heating device 2 arranged at a further lower position than the cooling unit 3a; a displacement device 15 for changing a distance between the member 1 to be processed and the cooling unit 3a; a temperature sensor 5 for detecting a temperature of the member 1 to be processed; a control device 6 for controlling the induction heating device 2 and the cooling device 3 based on the detected temperature; and an input device 7 for inputting a signal to the control device 6.

[0046] According to the present invention, since the induction heating coil 2a and the cooling unit 3a are arranged in a vertical installation orientation with respect to the member 1 to be machined, the apparatus can be miniaturized to a greater extent compared to the conventional case in which a heating unit and the cooling unit are arranged in a horizontal installation orientation thereto.

[0047] Below, each component is described in detail with regard to its configuration.

[0048] The processing chamber 4 is constructed to have an airtight chamber comprising a lid unit 4a and a bottom unit 4b. The lid unit 4a is supported on an axis 9 extending from an opening / closing device 8 and moves up and down with the axis 9 as determined by a Fig. 1, and can perform an opening / closing operation on the bottom unit 4b. Heat-shielding covers 10a and 10b may be attached to the inner side of the upper surface of the lid unit 4a so as to reflect infrared radiation emitted from the member 1 to be processed and return the light into the member 1 to be processed. At this time, the heat-shielding covers 10a and 10b are configured to prevent interference with the heating generated by the induction heating device 2. On the other hand, an evacuation device 11 is connected to the processing chamber 4 and evacuates the processing chamber 4. Further, a reducing gas supply device 12 and an inert gas supply device 13 are connected to the processing chamber 4 and supply a reducing gas and an inert gas, respectively, to the processing chamber 4.

[0049] The induction heating device 2 is composed of an induction heating coil 2a and a power supply 2b. Induction heating is described as a process in which an alternating current is applied to the induction heating coil 2a, and then the workpiece 1 is heated by Joule heat due to an eddy current generated in a conductive part of the workpiece 1 with the change in the magnetic flux. Compared to other non-contact heating devices, the structure is simple and miniaturized to such an extent that it can even be installed in the processing chamber 4. Furthermore, since there are no wear-prone components, it is suitable for maintenance-free continuous operation.

[0050] However, when the member 1 to be machined is made of a metal that is a non-magnetic material with low electrical resistance, such as copper, it is difficult to perform direct induction heating. Then, the member 1 to be machined is placed on a heated member made of a material that can be heated by induction heating and then heated by induction heating using the induction heating coil 2a, being heated indirectly by heat conduction from the heated member that has been heated. A shell 1d formed from the heated member is preferably made of, for example, carbon or a metal with high electrical resistance, and its shape is not limited to a specific one. Moreover, the heated member is not essential for manufacturing special components.The shell 1d formed of carbon or the like can achieve a similar effect.

[0051] The shape of the induction heating coil 2a is not limited to a specific shape. For example, in a state where a conductive wire is wound, a flat plate whose outer shape of the main surface has a circular or vertically oriented elliptical shape with a space around its center, or another flat plate whose outer shape of the main surface has a bottle-gourd shape with a constriction around its center, can be used.

[0052] A cooling device 3 is composed of the cooling unit 3a, a heat exchanger 3b, a coolant line 3c that circularly connects the cooling unit 3a and the heat exchanger 3b, a circulation pump 3d that circulates a coolant filled in the coolant line 3c between the cooling unit 3a and the heat exchanger 3b, and a flow control valve 3e for adjusting the flow rate of the coolant circulating through the cooling unit. Of these components, the heat exchanger 3b, the circulation pump 3d, and the flow control valve 3e are arranged outside the processing chamber 4. The heat exchanger 3b is configured so that a fluid flowing through another line (not shown) flows to cool the coolant flowing in the coolant line 3c through heat exchange between the coolant and the fluid.

[0053] A method for operating the cooling device 3 is not limited to a specific method. For example, while the circulation pump 3d is continuously operating, the coolant distribution to the cooling unit 3a can be interrupted or regulated in terms of flow rate by the flow regulating valve 3e. More specifically, when the member 1 to be processed is heated, the coolant circulation to the cooling unit 3a can be interrupted. During a period in which the member 1 to be processed is maintained at a constant temperature, the flow rate of the coolant can be adjusted with the flow regulating valve 3e in conjunction with an amount of electric current related to the AC power flowing through the induction heating coil 2a and / or a wave number thereof.When the member 1 to be machined is cooled, the power supply to the induction heating coil 2a is interrupted and then increasing the amount of coolant circulation to the cooling unit 3a by widely opening the flow regulating valve 3e allows the member 1 to be machined to be cooled rapidly.

[0054] The cooling unit 3a may be formed, for example, from a plate-like member having a flow path through which a coolant circulates, and disposed on the bottom unit 4b in the processing chamber 4. The quality of the material of the cooling unit 3a is not limited to any specific grade, but it preferably has sufficient heat-resistant properties and excellent heat transfer properties. Furthermore, when the non-contact heating device corresponds to the induction heating device, the cooling unit 3a is preferably an insulator through which the magnetic flux passes, so that induction heating does not occur. Specifically, silicon carbide, ceramics, quartz glass, and the like can be used. In particular, silicon carbide is preferably used because it has excellent thermal conductivity.

[0055] Furthermore, the induction heating coil 2a can be formed from a hollow structure tube. The coolant line 3c is then branched at a point just before the flow control valve 3e on the outlet side of the circulation pump 3d, allowing the coolant to be distributed to the induction heating coil 2a. This allows the induction heating coil 2a to be cooled.

[0056] A transfer device 15 is composed of a frame 15a for supporting the workpiece 1, a plurality of lifting axes 15b for moving the frame 15a up and down, a lifting base 15c to which the lifting axes 15b are attached, and a lifting actuator 15d for driving the lifting base 15c. The workpiece 1 is transferred up and down, resulting in a change in the distance between the workpiece 1 and the cooling unit 3a. When the lifting actuator 15d is retracted, the lifting base 15c is lifted, and the workpiece 1, which is supported on the frame 15a supported at the respective edges by the lifting axes 15b, is lifted to move away from the cooling unit 3a.In contrast, when the lifting actuator 15d is extended, the lifting base 15c is displaced downward, and the workpiece 1, which is supported on the frame 15a held at the respective edges by the lifting axes 15b, is displaced downward to contact the cooling unit 3a. When a temperature increase occurs in the workpiece 1, the workpiece 1 is moved away from the cooling unit 3a to achieve rapid heating. Furthermore, when the workpiece 1 is maintained at a constant temperature, the cooling unit 3a is brought close to the workpiece 1 to achieve a balance between heating and cooling. As a result, the temperature of the workpiece 1 can be precisely controlled.Furthermore, in the case where a temperature reduction is carried out in the element 1 to be processed, the element 1 to be processed is applied to the cooling unit 3a so that it is cooled quickly.

[0057] Furthermore, the displacement device 15 may be another type of device that displaces the cooling unit 3a to change a distance between the member 1 to be processed and the cooling unit 3a while maintaining the position of the member 1 to be processed.

[0058] A temperature sensor 5 is not limited to a specific sensor. For example, a thermocouple, an infrared emission thermometer, and the like can be used. However, it is preferable that the temperature sensor 5 be a type of sensor that is not affected by induction heating or has an electromagnetically shielded structure so that direct induction heating cannot occur. In the examples described above, the infrared emission thermometer is the type of temperature sensor that is not affected by induction heating. When the temperature sensor 5 corresponds to the thermocouple, it is preferable that a core part of the wire is shielded with a sheath so that direct heating by induction heating is avoided.Furthermore, when the temperature sensor 5 is in contact with the cooling unit 3a near its edge, the temperature sensor can receive an influence from the cooling unit 3a whose temperature is low. Then, it is preferable to provide at least one gap between the edge of the temperature sensor 5 and the cooling unit 3a. The temperature sensor may be provided in multiples. Input values ​​obtained from the plurality of sensors are calculated to obtain an average, so that deviation from a target value can be minimized. This increases temperature reliability.

[0059] The evacuation device 11 consists of a line 11b with a valve 11a and a vacuum pump 11c. The vacuum pump 11c is not limited to any specific pump. For example, a centrifugal pump, a diaphragm pump, a piston pump, and the like can be used. However, when evacuating a reducing gas, the vacuum pump 11c is preferably an explosion-proof pump for safety reasons.

[0060] The reducing gas supply device 12 consists of a line 12b with a valve 12a and a reducing gas cylinder 12c. Gases used as the reducing gas may include, for example, hydrogen, formic acid, formaldehyde, or the like.

[0061] The inert gas supply device 13 consists of a line 13b with a valve 13a and an inert gas cylinder 13c. Gases used as inert gases can include, for example, nitrogen, argon, or the like.

[0062] The control device 6 includes at least a memory formed from a RAM, a ROM, a magnetic disk, an optical disk, and the like; and an arithmetic logic unit including a CPU (not shown in the figures) configured to transmit a control signal to the respective devices through the arithmetic logic unit based on a program and data stored in the memory. Input means and a display means formed from a display, a printer, and the like (not shown) are connected to the control device 6. The data stored in the memory of the control device 6 can be input from the input means 7 connected to the control device 6.The data input by the input device 7 includes, for example, a dwell time t1, a dwell time t2, a first target heating temperature T1, a second target heating temperature T2, a first target cooling temperature T3, a second target cooling temperature T4, and the like. Furthermore, as described above, a temperature T of the element 1 to be processed, which is determined by the temperature sensor 5, and the like are input to the control device 6.

[0063] The control device 6 is connected to the opening / closing device 8, and the lid unit 4a of the processing chamber 4 can be displaced up and down with a control signal a. Furthermore, the control device 6 is connected to the power supply 2b of the induction heating device 2 and is capable of controlling the output of the induction heating coil 2a with a control signal b. For example, the wave number and the amount of electric current can be controlled with respect to the AC power applied to the induction heating coil 2a. Furthermore, the control device 6 is connected to the heat exchanger 3b of the cooling device 3 and is capable of controlling a temperature of the coolant with a control signal c. Furthermore, the control device 6 is connected to the flow regulating valve 3e of the cooling device 3 and is capable of controlling the coolant flow rate with a control signal d.Furthermore, the control device 6 is connected to the valve 11a of the evacuation device 11 and is capable of opening and closing the valve 11a with a control signal e. Furthermore, the control device 6 is connected to the vacuum pump 11c of the evacuation device 11 and is capable of switching the vacuum pump 11c on and off with a control signal f. Furthermore, the control device 6 is connected to the valve 12a of the reducing gas supply device 12 and is capable of opening and closing the valve 12a with a control signal g. Furthermore, the control device 6 is connected to the valve 13a of the inert gas supply device 13 and is capable of opening and closing the valve 13a with a control signal h.Furthermore, the control device 6 is connected to the lifting actuating device 15d of the displacement device 15 and is able to control a distance between the element 1 to be processed and the cooling unit 3a with a control signal i.

[0064] The control device 6 can thus control the temperature of the element 1 to be processed with parameters such as the wave number and the applied current applied to the induction heating coil 2a, the flow rate and the temperature of the coolant supplied to the cooling unit 3a at an inlet and the distance between the element 1 to be processed and the cooling unit 3a.

[0065] Hereinafter, the heating and cooling device 100 according to the present invention will be described with reference to an example of embodiments in the case of soldering a semiconductor module.

[0066] The member to be processed 1 is configured, for example, from a semiconductor element 1a, an insulating substrate 1b having a metal foil on each of its two surfaces, a base plate 1c, and a tray 1d. A plurality of semiconductor elements may be incorporated in the member to be processed 1. The semiconductor element is bonded by solder paste at a predetermined position where the metal foil is attached to the upper surface of the insulating substrate. Furthermore, the base plate 1c is bonded to the metal foil disposed on the underside of the insulating substrate 1b by solder paste. When the tray 1d, which also serves as a transfer jig, is placed on the cooling unit 3a, it is configured so that the lower surface of the tray 1d abuts against the upper surface of the cooling unit 3a and the edge of the temperature sensor 5 embedded in the cooling unit 3a.

[0067] The quality of the material for the shell 1d is not limited to any particular grade. Insulating materials such as ceramics and quartz glass, and high-resistivity materials such as carbon or the like can be used. When the shell 1d is made of the insulating material, the base plate 1c can be directly heated by induction heating due to the transmitted magnetic flux. On the other hand, when the shell 1d is formed of the high-resistivity material, the base plate 1c can be indirectly heated by conduction from the induction-heated shell 1d. This configuration allows the uniform heating of the workpiece 1 regardless of the material quality of the base plate 1c. Furthermore, the shape of the shell 1d can be appropriately changed so that the shell 1d can accommodate multiple base plates 1c and perform heating and cooling processes.A method for soldering the semiconductor module according to the heating and cooling device 100 will be described below. (1) Enter

[0068] The processing chamber 4 is opened, the lid unit 4a of the processing chamber 4 being raised using the opening / closing device 8, and the member 1 to be processed is inserted and placed on the frame 15a. After that, the lid unit 4a of the processing chamber 4 is moved downward using the opening / closing device 8, and then the processing chamber 4 is closed to ensure airtightness. (2) Evacuation

[0069] The valve 11a of the evacuation device 11 is opened, and then the interior of the processing chamber 4 is evacuated using the vacuum pump 11c. The valve 11a is closed when the vacuum level reaches a predetermined value. However, the valve 11a can be opened if the reduction reaction is carried out under reduced pressure. (3) Introducing the reducing gas

[0070] The reducing gas is introduced from the reducing gas cylinder 12c by opening the valve 12a of the reducing gas supply device 12. When the reducing gas has been supplied to the processing chamber 4 at a predetermined pressure, the valve 12a is closed. However, if the reduction reaction is carried out under reduced pressure, the valve 12a remains open, and a different predetermined pressure can be maintained by compensating with an evacuation rate. (4) First heating (reduction process)

[0071] Using the induction heating device 2, the member 1 to be processed is heated to the first target heating temperature T1, and the temperature T of the member 1 to be processed, which is detected by the temperature sensor 5, remains the first target heating temperature T1 for the residence time t1. Then, the member 1 to be processed is preliminarily heated, and the surface of the member 1 to be processed is reduced to increase wettability for soldering. The member 1 to be processed is held in a state in which a gap is created using the displacement device 15 so that contact with the cooling unit 3a is avoided during heating. This can prevent heat from flowing from the member 1 to be processed to the cooling unit 3a, thereby rapidly heating the member 1 to be processed. The first target heating temperature T1 is set to be lower than a solder melting temperature.If the solder is melted before the surface of the element 1 to be machined is sufficiently reduced, a cold joint may occur because defects are created in the joint. Thus, it is necessary to control the temperature T of the element 1 to be machined in such a way that overloads are avoided. The control device 6 can perform feedback control with respect to the output signal of the induction heating device 2 so that the deviation from the first target heating temperature T1 with respect to the temperature T detected by the temperature sensor 5 is minimized.

[0072] The heating and cooling device 100 according to the present invention has the advantage of a high temperature rise rate because it employs a method of directly heating the workpiece 1 as a heating element using the induction heater 2. This can thus shorten the heating time and increase the throughput of the heating and cooling device. (5) Second heating (solder melting)

[0073] Using the induction heating device 2, the member 1 to be processed is heated to the second target heating temperature T2, and the temperature T of the member 1 to be processed, which is detected by the temperature sensor 5, remains at the second target heating temperature T2 for the dwell time t2 to melt the solder placed on the member 1 to be processed. The second target heating temperature T2 is set to be higher than the solder melting temperature. If the second target heating temperature T2 is set higher than the solder melting temperature, a solid-phase reaction may proceed excessively in the solder joint surface, resulting in a cold joint.In contrast, if the second target heating temperature T2 is set significantly closer to the solder melting temperature, the solder may not melt at locations where the temperature is not sufficiently increased due to heating unevenness in the heating plate, resulting in a cold joint. Thus, it is necessary to accurately determine the temperature T of the member 1 to be processed and properly control the temperature. The control device 6 can perform feedback control with respect to the induction heating device 2 so that the deviation from the second target heating temperature T2 with respect to the temperature T detected by the temperature sensor 5 is minimized.Parameters such as the wave number and applied current supplied to the induction heating coil 2a, the flow rate and temperature of the coolant supplied to the cooling unit 3a at an inlet, and the distance between the element 1 to be machined and the cooling unit 3a can be controlled. (6) Cooling (solder solidification)

[0074] After the heating by the induction heating device 2 has been stopped, the element 1 to be processed is brought into contact with or approached by the cooling unit 3a using the displacement device 15, whereby it is cooled by the cooling unit 3a. The control device 6 can further perform feedback control with respect to the cooling device so that the deviation from the first target cooling temperature T3 with respect to the temperature T detected by the temperature sensor 5 is minimized. The cooling unit 3a is constructed of a material that is not directly heated and thus does not cause a temperature increase. This provides rapid cooling of the element 1 to be processed, which leads to a shortening of the cooling time and thus increases the throughput of the heating and cooling device. (7) Introduction of inert gas

[0075] When the temperature T of the member 1 to be processed, detected by the temperature sensor 5, reaches the second target cooling temperature T4, the interior of the processing chamber 4 is evacuated using the vacuum pump 11 after opening the valve 11a of the evacuation device 11 in a state where the valve 12a of the reducing gas supply device 12 is closed. When the processing chamber 4 reaches a predetermined vacuum level, the valve 11a is closed, and the valve 13a of the inert gas supply device 13 is opened. The inert gas is supplied from an inert gas cylinder 13c of the appointment chamber 4. When the pressure of the processing chamber 4 returns to atmospheric pressure, the valve 13a is closed. During the above period, the member 1 to be processed continues to be cooled by the cooling unit 3a. (8) Discharge

[0076] When the processing chamber 4 is opened, the lid unit 4a of the processing chamber 4 is raised by the opening / closing device 8, and the member 1 to be processed is discharged. Then, the opening / closing device 8 lowers the lid unit 4a of the processing chamber 4, thereby closing the processing chamber 4.

[0077] As described above, the heating and cooling apparatus according to the present invention is configured such that the reduction process for improving solder wettability, the solder melting process, and the solder solidification process are performed in a processing chamber 4, which is miniaturized compared to a conventional soldering apparatus. Furthermore, the cooling unit 3a is arranged at a lower position than the member to be processed 1, and the induction heating coil 2a of the induction heating device 2 is arranged at a further lower position than the cooling unit 3a. According to this embodiment described above, even when the members to be processed 1 each having a different height are continuously processed, a distance between the member to be processed 1 and the induction heating coil 2a remains unchanged because the induction heating coil 2a is arranged at a lower position than the cooling device 3.This eliminates the need to readjust the height of the induction heating coil 2a. This can improve processing. Furthermore, only the semiconductor module, which is the component 1 to be processed, tends to be heated by the induction heating coil 2a, and the inner wall of the processing chamber 4 and the cooling unit 3a are barely heated. This avoids waste heat, further enabling both heating and cooling of the semiconductor module to be carried out quickly.

[0078] Hereinafter, the induction heating device of the heating and cooling apparatus according to the present invention will be described in detail in conjunction with the figures.

[0079] As described above, when the member 1 to be processed, which is the semiconductor module, is configured such that the semiconductor element 1a, the insulating substrate 1b, and the base plate 1c formed of copper are bonded together with solder, it is difficult to heat each part thereof by induction heating. Then, it is easy to heat the parts indirectly by heat conduction from a heated member. It is preferable that the base plate 1c be placed, for example, on the tray 1d formed of the carbon material. In order to uniformly heat the member 1 to be processed, it is preferable that an outer shape of the tray 1d is larger than an outer edge of the area in which a plurality of base plates 1c are placed, and an outer shape of the induction heating coil 2a is preferably larger than the outer shape of the tray 1d.

[0080] The shape of the induction heating coil 2a used in the present invention is not limited to a specific shape. For example, the shape shown in Fig. 2 Induction heating coil shown in the top view can be used for this purpose. Fig. Figure 2 illustrates only the outer shape of a winding bundle, but does not show the shape of the conductive wire. Furthermore, the shell 1d, which is made of the heated element, is shown as rectangular. Fig. 2a shows a flat-shaped induction heating coil 2aa in a state in which the conductive wire is wound so that an outer shape of the main surface having a space around its center is circular. Fig. Fig. 2b shows another flat-shaped induction heating coil 2ab in a state in which the conductive wire is wound so that the outer shape of the main surface, which has a further space around its center, is elliptical in the vertical direction. Fig. Figure 2c shows another flat-shaped induction heating coil 2ac in a state where the conductive wire is wound such that the outer shape of the main surface, which has a further space around its center with a constriction positioned around the center, is elliptical in the vertical direction, namely, a gourd-shaped shape. These induction heating coils can be coils in which the conductive wire is wound with an insulating cover, or other coils in which a tube with a hollow structure formed of a metal with excellent electrical conductivity is wound. Although it has a hollow structure, there is no influence on loss and heating characteristics because the current flows through the metal surface.

[0081] In addition, Fig. 2 schematically shows a high-temperature part HT and a low-temperature part LT with a hatching pattern when the shell 1d is heated by induction heating. Fig. In the circular coil shown in Figure 2aa, the high-temperature parts HT are generated around the four sides of the shell 1d and the low-temperature parts LT are generated at its four corners. In the Fig. 2, the high-temperature parts HT are generated around the center of the shell 1d and along the short sides. In particular, the shell 1d experiences an immediate temperature rise in its center because the center portion is simultaneously heated by the shell portions of the two vertically aligned elliptical coils. Therefore, when a gourd-shaped coil 2ac having the constriction S arranged around the center is used with the improvement of the vertically aligned elliptical coil 2ab, the heat concentration generated around the center portion of the shell 1d is attenuated, which improves thermal uniformity, as shown in FIG. Fig. 2c shows.

[0082] Furthermore, the bottle gourd-shaped coil 2ac is designed in terms of shape and configuration using Fig. 3 in detail. Six pieces of the elements 1 to be processed are placed on the upper surface of the tray 1d. Two pieces of the gourd-shaped coils 2ac, in which the constrictions S are placed close to each other, are arranged in parallel at a lower position than the tray 1d.

[0083] Here, the gourd-shaped coil 2ac preferably has a shape formed such that a space around the center and at least a part of the constriction S are located within the periphery of the shell 1d. This gathers the magnetic lines of force of the induction heating coil at the interior of the shell 1d, so that the shell 1d is effectively heated.

[0084] Increasing a distance L1 from one end of the gourd-shaped coil in the longitudinal direction to an outer edge of the tray 1d can increase a heating value at the point A of the tray 1d. Furthermore, increasing a distance L2 from the most protruding outer edge of the gourd-shaped coil to an outer edge of a member to be processed on a side having the constriction S of the gourd-shaped coil 2ac can increase another heating value at the point B of the tray 1d.

[0085] In the heating and cooling device according to the present invention, a distance L3 between the parallel-arranged gourd-shaped coils 2ac is preferably designed so that the calorific values ​​with respect to points A and B become almost equal to each other. More preferably, a position adjusting means is provided to adjust thermal uniformity with respect to the tray 1d. Further, a distance L4 between the gourd-shaped coil 2ac and the tray 1d is preferably designed so that an appropriate difference is achieved between the periphery and the interior with respect to the flat plate, taking into account the heat loss from the periphery of the flat plate. Therefore, more preferably, another position adjusting means is provided to adjust thermal uniformity with respect to the tray 1d.

[0086] Furthermore, in the heating and cooling device according to the present invention, the winding directions of adjacent gourd-shaped coils 2ac are preferably opposite to each other. This configuration can efficiently heat the tray 1d because the magnetic field generated by the two induction heating coils 2ac acts to enhance the eddy current.

[0087] In the heating and cooling device according to the present invention, a soft magnetic member 16 is preferably provided at a lower position than the adjacent gourd-shaped coils 2ac. This configuration can connect magnetic lines of force extending in a lower direction than an induction heating coil with other magnetic lines of force of the gourd-shaped coil 2ac through the soft magnetic member 16, thus reversing the magnetic field generated around the bottom of the gourd-shaped coil 2ac to an upward direction. Furthermore, the magnetic flux density distribution on the tray 1d can be adjusted by adjusting the configuration of the soft magnetic member 16 relative to the gourd-shaped coil 2ac.

[0088] Furthermore, although the induction heating coil is not limited to the gourd-shaped coil, it corresponds to another type of the same with a different shape, the heating and cooling device according to the present invention may include a position adjusting device capable of changing the distance L3 between parallel-arranged induction heating coils and a position adjusting device capable of changing the distance L4 between the induction heating coil and the member 1 to be machined. The configuration may then be such that the respective winding directions are reversed from those of adjacent induction heating coils. The soft magnetic component may then be arranged at a lower position than the induction heating coil.

[0089] Furthermore, an example in which two induction heating coils are arranged as shown above will be described. However, one or more induction heating coils arranged in parallel may be provided.

[0090] Hereinafter, in the heating and cooling device according to the present invention, another embodiment in which an aspect of the cooling unit is changed will be described in conjunction with the figures.

[0091] Fig. 4 shows a heating and cooling device 101 in which another cooling unit is formed from the induction heating coil 2a, which has a hollow structure in which a flow path capable of circulating coolant is formed, and which serves not only as a cooling unit but also as a heating unit. When the displacement unit 15 abuts the tray 1d against the induction heating coil 2a serving as the cooling unit, the tray 1d can be directly cooled. The surface in contact with the tray 1d is preferably flattened with respect to the cross section of the induction heating coil 2a in order to increase the contact area with the tray 1d. More specifically, the cross section preferably has a rectangular shape with the hollow structure. This configuration allows the coolant to circulate through the induction heating coil 2a with the hollow structure, thereby suppressing self-heating of the induction heating coil 2a.This saves installation space, which leads to a miniaturization of the processing chamber, since the induction heating coil 2a serves as both a heating unit and a cooling unit.

[0092] Fig. 5 illustrates a heating and cooling device 102 in which yet another cooling unit serves not only as the cooling unit but also as the heating unit, and which is composed of: the induction heating coil 2a having the hollow structure in which the flow path through which the coolant can circulate is formed; a cooling plate 3f formed of an insulating material and arranged at a higher position than the induction heating coil 2a; and a support plate 3g formed of a different insulating material and arranged at a lower position than the induction heating coil 2a. When the transfer device 15 abuts the member 1 to be machined against the cooling plate 3f, the member 1 to be machined can be directly cooled. At this time, if the heat capacity of the cooling plate 3f is excessively large, the heating or cooling response becomes poor, resulting in a longer processing time.Therefore, it is desirable that cooling capacity adjustment and temperature fluctuation stabilization should be performed so that the absorbed heat balances the heat capacity of the cooling plate 3f depending on a coolant circulation speed.

[0093] According to the above aspect of the invention, the induction heating coil 2a serves as both a heating unit and a cooling unit, and the saving of installation space leads to miniaturization of the processing chamber.

[0094] Fig. 6 shows yet another embodiment of the heating and cooling device according to the present invention. Fig. 6a shows a state in which the element 1 to be processed is separated from the cooling unit 3a, and Fig. 6b shows another state in which the member 1 to be machined is in contact with the cooling unit 3a. A heating and cooling device 103 includes two groups of induction heating coils 2a and cooling units 3a in a processing chamber and is configured to process two pieces of the members 1 to be machined simultaneously. According to the above-described aspect, all parts except the induction heating coils 2a and the cooling units 3a are shared, and twice as many heating and cooling units are accommodated as in conventional ones. This reduces costs and improves process throughput.

[0095] Furthermore, although the case where two groups of induction heating coils 2a and cooling units 3a are used is described above, multiple groups, meaning two or more, may be provided in other cases. Furthermore, each group can be operated simultaneously with one lift actuator 15d or individually with respective lift actuators 15d installed for each group. By operating each of these groups individually, a distance between the workpiece 1 and the cooling unit 3a can be individually adjusted. This results in easy temperature control.

[0096] Fig. Figure 7 shows yet another embodiment of the heating and cooling device according to the present invention. A heating and cooling device 104 is configured such that the non-contact type induction heating coil 2a of the induction heating device 2 is arranged at a higher position than the workpiece 1, and the cooling unit 3a of the cooling device 3 is arranged at a lower position than the workpiece 1. Other structures are shown in Fig. 1 shown embodiment.

[0097] According to the above-described embodiment, the member 1 to be machined can be heated efficiently because the member 1 to be machined can be brought to a shorter distance from the induction heating coil 2a. Furthermore, since there are no obstacles between the induction heating coil 2a and the member 1 to be machined, the heating efficiency can be further improved.

[0098] Furthermore, in the configuration using the induction heating coil 2a with the hollow structure, the coolant line 3c is branched from the side of the flow control valve 3e to the outlet side of the circulation pump 3d. The circulation of the coolant through the induction heating coil 2a ensures the cooling of the induction heating coil 2a.

[0099] Fig. 8 shows another aspect that is different from the Fig. 7 shown heating and cooling device is modified.

[0100] A heating and cooling device 105 is configured such that the induction heating coil 2a, which corresponds to the non-contact type, is arranged at a lower position than the cooling unit 3a of the cooling device 3. This structure is configured such that the cooling unit 3a is arranged at a lower position than the tray 1d on which the workpiece 1 is placed, and the induction heating coil 2a is arranged at an even lower position than the cooling unit 3a. Other structures are similar to the embodiment.

[0101] According to the above-described embodiment, even when the workpieces 1 to be machined are continuously machined, each with a different height, the distance between the workpiece 1 and the induction heating coil 2a remains unchanged because the induction heating coil 2a is arranged at a lower position than the cooling device 3. This can avoid the need to readjust the height of the induction heating coil 2a, thus improving the machining.

[0102] Furthermore, the induction heating coil 2a can be arranged at a higher position than the workpiece 1 and also at a lower position than the cooling unit 3a. Such a configuration achieves even better thermal uniformity, since the workpiece 1 is heated from both above and below.

[0103] Fig. 9 shows yet another embodiment of the heating and cooling device according to the present invention.

[0104] A heating and cooling device 106 is configured such that the induction heating coil 2a is housed in a coolant tank 3h of the cooling device 3. Furthermore, since another flow path for the circulation of another coolant is formed in the coolant tank 3h, the induction heating coil 2a is in a state of being immersed in the coolant circulating through the flow path.

[0105] The coolant tank 3h is housed in a platform 3g' whose upper part is open and sealed with a cooling plate 3f. Furthermore, a coolant inlet 3i and a coolant outlet 3j are provided at the lower part of the coolant tank 3h. The coolant, which is, for example, cooling water, is introduced through the coolant inlet 3i and discharged from the coolant outlet 3j. This ensures the cooling of the induction heating coil 2a and the cooling plate 3f resting against the upper surface of the coolant tank 3h.

[0106] Fig. Figure 9a shows a way in which the workpiece 1 is heated. When the workpiece 1 is heated, an alternating current is applied to one terminal 2c of the induction heating coil 2a. In fact, there are also other terminals 2c, not shown, in the induction heating coil 2a arranged on the right side with respect to the temperature sensor 5, and then the alternating current is applied to the other terminal 2c.

[0107] The tray 1d, on which the workpiece 1 to be machined is placed, is connected to the lifting axis 15b of the displacement device 15. During heating, the tray 1d is lifted using the displacement device 15 to a position at least 3 mm or more away from the cooling plate 3f. However, the induction heating coil 2a can heat the workpiece 1 on a non-contact basis because the eddy current is generated at a conductive part of the workpiece 1 to be machined.

[0108] Below shows Fig. Figure 9b shows a manner in which the element 1 to be machined is cooled. As shown in the figure, the displacement device 15 allows the tray 1d to lower during cooling, thereby allowing the tray 1d to come into contact with the cooling plate 3f. This ensures rapid cooling of the element 1 to be machined by the cooling plate 3f.

[0109] According to the present embodiment, the coolant circulating in the coolant tank 3h is in direct contact with the cooling plate 3f, reducing the loss of cooling capacity. Furthermore, a shape constraint on the induction heating coil 2a is shortened. This ensures a sufficient number of windings and provides a way to use a low-loss stranded wire.

[0110] Fig. 10 shows yet another embodiment of the heating and cooling device according to the present invention.

[0111] First, a heating and cooling device 107 has a feature in the transfer device 15 and particularly in a part in which the tray 1d is placed. As Fig. As shown in Fig. 10, the lifting base 15c, which is flat in shape, is connected to the lifting actuator 15d of the displacement device 15. Further, the lifting axis 15b, which is fixed to the base 15c and then inserted through the bottom 4b of the processing chamber 4, is installed to be moved up and down by lifting bearings 15e arranged in the bottom 4b.

[0112] Fig. 10b shows an enlarged view of the Fig. 10a with R. As Fig. 10b, a bearing support 15f is provided on the other side of the lifting axis 15b. Furthermore, a connecting plate 15g is provided, which has a pair of bearing supports 15f, the two in Fig. 10a. Furthermore, a support unit 15h, which supports the edge of the bottom surface of the tray 1d on which the member to be machined 1 is placed and which is formed of a heat-resistant insulating material such as, for example, an engineering plastic including ceramic, polyimide, or a PEEK plate, is attached to the connecting plate 15g.

[0113] The support unit 15h is configured so that the workpiece 1 avoids interference with the cooling plate 3f and an insulating cover 2d described below when the transfer device 15 allows the workpiece 1 to be lowered. The transfer device 15 with this configuration enables smooth movement of the support unit 15h while holding the tray 1d when the actuating device 15d is moved up and down in response to a command from the control device 6.

[0114] The heating and cooling device 107 has another feature regarding the cooling device 3. The cooling plate 3f, which is arranged to absorb heat from the workpiece 1 and the tray 1d heated to a higher temperature by induction heating, is formed in close contact with the surface side of the induction heating coil 2a with a hollow structure, thus achieving better heat transfer. The cooling plate 3f, which is made of ceramics with excellent thermal conductivity, such as SiC, AlN, and the like, is preferably formed to have a greater thickness than the workpiece 1, so that the heat capacity is increased.

[0115] Further, the support plate 3g formed of insulating material such as plastic, ceramic, and the like is provided to fix the shape and position of the induction heating coil 2a at a bottom of the induction heating coil 2a.

[0116] In order to heat the workpiece 1 placed on the rectangular tray 1d, the induction heating coil 2a must have a larger dimension than the cooling plate 3f to minimize temperature unevenness. This results in an exposed upper surface of the induction heating coil 2a.

[0117] The upper surface of the induction heating coil 2a is covered with a heat-resistant insulating material, such as poly(tetrafluoroethylene) resin, polyimide, or machinable ceramic. The insulating cover 2d, which is formed to prevent interference with the support unit 15h, is then attached to the support plate 3g.

[0118] At this time, a recess is provided on the underside of the cooling plate 3f so that the formation of a gap at the position between an edge of the cooling plate 3f and the edge of the insulating cover 2d is avoided, while allowing the tip of the insulating cover 2d to be inserted into the recess part of the cooling plate 3f (see Fig. 10b).

[0119] When the workpiece 1 and the tray 1d are attached and detached, attaching the insulating cover 2d formed as described above can prevent conductive particles from accumulating on the induction heating coil 2a during extended operation. This can effectively prevent short circuits and discharges.

[0120] Further, a spacer 2e formed of the insulating material is inserted at the position between the leads constituting the induction heating coil 2a, thus preventing the occurrence of a short circuit and discharges when the induction heating coil 2a is energized.

[0121] Fig. 11 shows yet another embodiment of the heating and cooling device according to the present invention.

[0122] A heating and cooling device 108 is configured to heat the workpiece 1 arranged on the tray 1d with the induction heating coil 2a. The transfer device 15 allows the tray 1d to be raised during heating. Furthermore, during cooling, the transfer device 15 allows the tray 1d to lower, thereby allowing the tray 1d to come into contact with the cooling plate 3f. As a result, the heat from the tray 1d is conducted to the cooling plate 3f, resulting in dissipation. This accomplishes the cooling of the workpiece 1.

[0123] During cooling, the shell 1d may warp due to thermal deformation of the shell 1d or bend downward due to the weight of the component 1 being processed. In this case, the area where the shell 1d contacts the cooling plate 3f may decrease, resulting in insufficient cooling performance. If sufficient cooling performance is not achieved, the components become coarse and easily develop cracks when creep deformation occurs. This leads to a long-term deterioration in reliability in terms of the strength of the solder joint.

[0124] Thus, a heating and cooling device 108 is configured such that a shell pressing system 17 applies pressure to the periphery of the shell 1d and presses the shell 1d against the cooling plate 3f. This enables the contact between the shell 1d and the cooling plate 3f to always be excellent.

[0125] However, the shell 1d is often made of carbon material and therefore lacks sufficient strength. Thus, there is a risk of breakage. If the shell 1d is pressed too aggressively against the cooling plate 3f by the shell pressing system 17, the shell 1d will be subject to wear and eventually break.

[0126] For this reason, the cooling status can be determined while monitoring the temperature of the tray 1d with the temperature sensor 5 and while further monitoring the temperature of the cooling plate 3f with a cooling plate temperature sensor 18 in order to improve the contact area between the tray 1d on which the member to be machined 1 is placed and the cooling plate 3f when the tray 1d is pressed against the cooling plate 3f.

[0127] The control device 6 of the heating and cooling device 108 determines in real time, using the method described above, whether the contact state between the shell 1d and the cooling plate 3f is excellent or not, and then, using a signal line j, controls the shell pressing system 17 such that the shell 1d is pressed only when the contact state is poor. This prevents the shell pressing system 17 from pressing the shell 1d more than necessary. This can thus lead to a reduction in breakage.

[0128] As described above, the heating and cooling device 108 can improve the contact state between the shell 1d and the cooling plate 3f and then maintain a predetermined cooling characteristic. The member 1 to be processed can thus be cooled quickly, preventing the solder components from becoming coarse. This results in an excellent solder joint condition.

[0129] Finally, an output control is described as a further feature of the heating and cooling device 108. The heating and cooling device 108 has a circuit configuration similar to that of the Fig. 1. However, there are differences in that a pressure gauge 19 is provided to determine the pressure in the processing chamber 4, as well as a drain valve 20 and a drain line 21 to relieve the pressure in the processing chamber 4.

[0130] If the pressure in the airtight processing chamber 4 is more than a constant pressure, for example, above atmospheric pressure, the control device 6 can open the drain valve 20 connected to the drain line 21 and release the pressure. The control device 6 is configured to actuate the opening / closing movement of the drain valve 20 through a signal line k, thus controlling the pressure in the processing chamber 4.

[0131] Furthermore, when another signal is transmitted from the pressure gauge 19 to the control device 6, the control device 6 is configured to control the opening / closing movement of the valve 11a and the operation of the vacuum pump 11c.

[0132] The control device 6 can thus control the temperature of the element 1 to be machined using parameters such as the wave number and the applied current applied to the induction heating coil 2a, the flow rate and the temperature of the coolant supplied to the cooling unit 2a with the hollow structure at the inlet, a pressure Pr in the processing chamber 4 and the distance between the element 1 to be machined and the cooling unit 3a.

[0133] Hereinafter, a method of soldering a power semiconductor device using the heating and cooling device 108 will be described mainly based on points different from the use of the heating and cooling device 100 described above. (1) Enter

[0134] The opening / closing device 8 allows the lid unit 4a of the processing chamber 4 to be raised to open the processing chamber 4, and then the element 1 to be processed is inserted. The element 1 to be processed is placed on the frame 15a, and then the opening / closing device 8 lowers the lid unit 4a of the processing chamber 4, thus closing the processing chamber 4. This creates a closed space. (2) Evacuation

[0135] The valve 11a of the evacuation device 11 is opened, and then the interior of the processing chamber 4 is evacuated using the vacuum pump 11c. Then, the valve 11a is closed when the reading of the pressure gauge 19 approaches a predetermined vacuum level. (3) Introducing the reducing gas

[0136] The reducing gas is introduced from the reducing gas cylinder 12c by opening the valve 12a of the reducing gas supply device 12. When the internal pressure of the processing chamber 4 approaches the atmosphere, the vent valve 20 is opened, and then a supply flow rate of the reducing gas is adjusted with the valve 12a.

[0137] In the case where the reduction reactions are carried out in a state where the processing chamber 4 is depressurized, the valve 12a is closed to seal the processing chamber 4 when another reading of the pressure gauge 19, which determines the pressure state of the processing chamber 4, reaches a predetermined pressure. This results in the pressure being maintained under airtight conditions. (4) First heating (reduction process)

[0138] Using the induction heating device 2, the member 1 to be processed is heated to the first target heating temperature T1, and a temperature T of the member 1 to be processed, which is detected by the temperature sensor 5, is maintained at the first target heating temperature T1 for the residence time t1, so that the member 1 to be processed is preheated, and a reduction reaction is performed on the surface of the member 1 to enhance wettability for brazing. The member 1 to be processed is held in a state in which a gap is created using the displacement device 15, so that contact with the cooling unit 3a is avoided during heating. Consequently, hardly any heat is lost from the member 1 to be processed to the cooling unit 3a. Then, the member to be processed can be heated quickly.The control device 6 can perform a feedback control with respect to the output signal of the induction heating device 2 so that the deviation from the first target heating temperature T1 with respect to the temperature T determined by the temperature sensor 5 is minimized.

[0139] The element 1 to be processed is maintained at the first target heating temperature T1, and then the valve 12a of the reducing gas supply device 12 and the discharge valve 20 are closed after the residence time t1 has elapsed. Furthermore, the valve 11a of the evacuation device 11 is opened, and the vacuum pump 11c is started. The processing chamber 4 is then evacuated until its pressure reaches Pr1, and then the valve 11a is closed.

[0140] The control device 6 receives input data, which includes a further reading from the pressure gauge 19 installed in the processing chamber 4 and the distance between the cooling plate 3f and the tray 1d on which the element 1 to be processed is placed. The control device 6 then converts the input data each time and outputs the maximum applied current or the maximum electrical power that can be supplied to the induction heating coil 2a without generating a discharge, thus controlling the heating until the second target heating temperature T2 is reached.

[0141] It is known that a discharge generated by the induction heating coil 2a varies with the electrical power applied to the induction heating coil and the product of pressure and distance in the processing chamber 4 (Paschen's law). In other words, the maximum applied current or the maximum electrical power is set so that the conditions are lower than those of the curve prescribed by Paschen's law. The second target heating temperature T2 is set to be slightly higher than the liquidus temperature TS of the solder material used in the member 1 to be processed. This has the effect of preventing the reducing gas in the processing chamber 4 from participating in the soldering process when the solder material is melted in a reduced-pressure environment. (5) Second heating (solder melting)

[0142] Using the induction heater 2, the member 1 to be processed is heated to the third target heating temperature T3. Then, another temperature T of the tray 1d on which the member 1 to be processed is placed, which is detected by the temperature sensor 5, is maintained for a dwell time t3 to be the third target heating temperature T3, thereby melting the solder placed on the member 1 to be processed. The third target heating temperature T3 is set to be sufficiently higher than the solder liquidus temperature TS, allowing the direct growth of alloy layers at solder bonding surfaces with respect to the molten solder material, the base plate 1c, and the insulating substrate 1b of the member 1 to be processed, and further at solder bonding surfaces between the insulating substrate 1b and its semiconductor element 1a.

[0143] The control device 6 can control the wave number and the applied current applied to the induction heating coil 2a of the induction heating device 2, the flow rate and the temperature of the cooling and circulating device that circulates the coolant, and the distance between the tray 1d on which the member to be machined 1 is placed and the cooling plate 3f, so that the deviation from the third target heating temperature T3 with respect to the temperature T detected by the temperature sensor 5 is minimized.

[0144] When the solder melting process under reduced pressure has been completed as described above, the valve 12a of the reducing gas supply device 12 is opened to regulate the pressure of the processing chamber 4 so that it reaches atmospheric pressure. When atmospheric pressure is reached, the opening degree of the valve 12a of the reducing gas supply device 12 is adjusted so that the flow of reducing gas into the processing chamber 4 is maintained. Then, the relief valve 20 is opened to prevent an overpressure condition in the processing chamber 4.

[0145] However, when the processing chamber is set to Pr2, which indicates the reduced pressure state, the control device 6 is configured to perform a conversion each time, in response to the pressure in the processing chamber 4 and the distance between the cooling plate 3f and the tray 1d on which the member to be processed 1 is placed, with respect to heating up to the third target heating temperature T3 of the member to be processed 1, and output the maximum application current or the maximum electric power applied to the induction heating coil 2a of the induction heating device 2, thereby controlling the temperature T of the member to be processed 1 and the tray 1d.

[0146] When the member 1 to be processed and the shell 1d reach the third target heating temperature T3 and then the predetermined residence time t3 has elapsed, the valve 12a of the reducing gas supply device 12 and the discharge valve 20 are closed. Then, the vacuum pump 11c of the evacuation device 11 is activated, and the corresponding valve 11a is opened. The reducing gas in the processing chamber 4 is expelled until another predetermined pressure is reached.

[0147] When the interior of the processing chamber 4 reaches a predetermined pressure, the valve 11a is closed, and then the valve 12a of the reducing gas supply device 12 is opened. This restores the atmospheric pressure in the processing chamber 4. Then, when atmospheric pressure is reached, the exhaust valve 20 is opened again. This operation can expel gases present in the solder of the member 1 to be processed, thereby reducing defects generated in the solder joint.

[0148] Furthermore, the control device 6 controls the wave number and the applied current or electric power supplied to the induction heating coil 2a of the induction heating device 2 until the member 1 to be processed reaches the third target heating temperature T3 during a predetermined dwell time t4. This process allows the solder joint surface of the member 1 to be processed to maintain the alloy layer with a predetermined thickness. (6) Cooling (solder solidification)

[0149] After the heating by the induction heating device 2 has been stopped, the element to be processed 1 is brought into contact with or approached by the cooling plate 3f using the displacement device 15, thereby being cooled by the cooling plate 3f. The control device 6 can further perform feedback control with respect to the cooling device so that the deviation from the first target cooling temperature T4 with respect to the temperature T detected by the temperature sensor 5 is minimized. The cooling plate 3f is formed of a material that is not directly heated and thus does not cause a temperature increase. This provides rapid cooling of the element to be processed 1, resulting in a shortening of the cooling time and thus increasing the throughput of the heating and cooling device. (7) Introduction of inert gas

[0150] When the temperature T of the member 1 to be processed, detected by the temperature sensor 5, reaches a second target cooling temperature T5, the valve 11a of the evacuation device 11 is opened in a state where the valve 12a of the reducing gas supply device 12 is closed, and then the interior of the processing chamber 4 is evacuated using the vacuum pump 11c. When another reading of the pressure gauge 19 of the processing chamber 4 reaches a predetermined vacuum level, the inert gas is supplied from an inert gas cylinder 13c to the processing chamber 4 while the valve 11a is closed, and then the valve 13a of the inert gas supply device 13 is opened. When the atmospheric pressure in the processing chamber 4 is restored, the exhaust valve 20 is opened, and the reducing gas is discharged to the exhaust line 21.Then, after a predetermined period of time has elapsed, the valve 13a and the exhaust valve 20 are closed. During the above-described period, the member 1 to be processed, placed on the cooling plate 3f, is continuously cooled. (8) Discharge

[0151] When the processing chamber 4 is opened, the lid unit 4a of the processing chamber 4 is raised by the opening / closing device 8, and the member 1 to be processed is discharged. Then, the opening / closing device 8 lowers the lid unit 4a of the processing chamber 4, thereby closing the processing chamber 4.

[0152] As described above, in the heating and cooling apparatus according to the present invention, the cooling plate 3f of the cooling device 3 is arranged at a lower position than the member 1 to be processed, so that it abuts against the induction heating coil 2a in which the coolant circulates. In fact, only up and down movements in a processing chamber 4 enable the apparatus to perform the reduction process for improving solder wettability, the solder melting process, and the solder solidification process. Compared to a conventional soldering apparatus, it is thus miniaturized.

[0153] According to the above-described embodiment, even when workpieces 1 with different heights are continuously machined, the distance between the workpiece 1 and the induction heating coil 2a remains unchanged because the induction heating coil 2a is arranged at a lower position than the cooling plate 3f. This eliminates the need to readjust the height of the induction heating coil 2a. This can improve machining.

[0154] Furthermore, since the induction heating coil 2a advantageously acts to heat only the semiconductor module of the member to be processed 1 smoothly and hardly heats the inner wall of the processing chamber 4 and the cooling unit 3a, heating losses can be eliminated, and both heating and cooling of the semiconductor module are carried out quickly.

[0155] Only a few embodiments according to the present invention are illustrated above, and other, modified embodiments can be considered in various ways. For example, the heating and cooling device can be configured in combination with respective components that correspond to the intended use, so that, for example, the tray pressing system 17 is used with the heating and cooling device 106, which includes the cooling container 3h.

[0156] A fluid such as water, pure water, antifreeze fluid, or the like capable of cooling the heat exchanger 3b can be used, and these are available for each configuration of the heating and cooling device. Furthermore, a sealing element such as an O-ring may be provided at the contact surface between the lid unit 4a and the bottom unit 4b of the processing chamber 4. When the opening / closing device 8 allows the lid unit 4a to be lowered onto the bottom unit 4b, the deformation of the elastic sealing element allows the airtightness of the processing chamber 4 to be maintained. LIST OF REFERENCE SYMBOLS 1 element to edit 1a Semiconductor element 1b Insulating substrate 1c base plate 1d bowl 2 induction heating device 2a Heating unit (induction heating coil) 2aa flat induction heating coil in which the outer shape of the main surface is circular (circular coil) 2ab flat induction heating coil in which the outer shape of the main surface is a vertically oriented elliptical coil (vertically oriented elliptical coil) 2ac induction heating coil in which the outer shape of the main surface is bottle gourd-shaped (bottle gourd-shaped coil) 2b Power supply 2c connection 2d insulation cover 2nd spacer 3 Cooling device 3a Cooling unit 3b Heat exchanger 3c coolant line 3D circulation pump 3e Flow control valve 3f cooling plate 3g support plate 3g' platform 3h coolant tank 3i coolant inlet 3j coolant outlet 4 processing chamber 4a Lid unit 4b Ground unit 5 Temperature sensor 6 Control device 7 Input device 8 Opening / closing device 9 Axis 10a, 10b Heat protection cover 11 Evacuation facility 11a Valve 11b line 11c Vacuum pump 12 Reducing gas supply facility 12a valve 12b line 12c cylinder for reducing gas 13 Inert gas supply facility 13a Valve 13b line 13c Inert gas cylinder 15 Relocation facility 15a frame 15b lifting axis 15c lifting base 15d Lifting actuator 15e pin bearing 15f bearing support 15g connecting plate 15h carrying unit 16 soft magnetic component 17 Shell pressing system 100-108 Heating and cooling device A, B Temperature reference position Pr Pressure S Constriction arranged longitudinally around the center of the bottle-gourd-shaped coil T, T' temperature L1 Distance from one end part of the bottle gourd-shaped coil in the longitudinal direction to the outer edge of the bowl L2 Distance from the most projecting edge of the gourd-shaped coil to the outer edge of the element to be machined on the side having the constriction S of the gourd-shaped coil L3 Distance between parallel arranged induction heating coils L4 Distance between induction heating coil and bowl LT low-temperature part HT high-temperature part

Claims

[1] Heating and cooling device (102) comprising: an airtight processing chamber (4) having an opening / closing system (8) capable of loading and unloading an element (1) to be processed; an induction heating device (2) containing one or more induction heating coils (2a) by which the element (1) to be processed is heated; a cooling device (3) which cools the element (1) to be processed; a temperature sensor (5) for determining a temperature of the element (1) to be processed; and and a control device (6) which controls the induction heating device (2) and the cooling device (3) on the basis of the temperature detected by the temperature sensor (5); wherein a displacement device (15) is arranged such that the element to be machined (1) and / or a cooling unit of the cooling device (3) are displaced in order to change a distance between the element to be machined (1) and the cooling unit of the cooling device (3), wherein the heating and cooling device (102) includes: a cooling plate (3f) which is arranged between the element to be machined (1) and the induction heating coil (2a). [2] The heating and cooling device (102) according to claim 1, wherein the induction heating coil (2a) is arranged at a lower position than the member (1) to be machined, and the cooling unit is configured to form a one-piece construction with a cooling system and the induction heating coil (2a). [3] The heating and cooling device (102) according to claim 2, wherein the cooling system, in which the induction heating coil (2a) has a hollow structure, is configured to form a flow path through which a coolant can circulate. [4] Heating and cooling device (102) according to claim 3, wherein the cooling unit preferably includes the cooling plate (3f) which rests against the upper surface of the induction heating coil (2a) with the hollow structure during the cooling process. [5] The heating and cooling device (102) according to claim 2, wherein the heating and cooling device (102) includes: another flow path through which a coolant other than the cooling system circulates and which is arranged at a lower position than the cooling plate, the induction heating coil (2a) being immersed in the coolant. [6] Heating and cooling device (102) according to claim 4, wherein the cooling plate is formed of ceramic such as silicon carbide, silicon nitride or aluminum nitride. [7] Heating and cooling device (102) according to claim 5, wherein the cooling plate is formed of ceramic such as silicon carbide, silicon nitride or aluminum nitride. [8] The heating and cooling device (102) according to claim 1, wherein an insulating cover (2d) formed of a heat-resistant insulating material is preferably arranged to cover a surface of the induction heating coil (2a). [9] Heating and cooling device (102) according to claim 1, wherein the cooling unit is arranged at a lower position than the member (1) to be machined and the induction heating coil (2a) is provided at a higher position than the member (1) to be machined. [10] The heating and cooling device (102) according to claim 1, wherein the cooling unit is arranged at a lower position than the member (1) to be machined, and the induction heating coil (2a) is provided at a different lower position than the cooling unit. [11] Heating and cooling device (102) according to claim 4, wherein control means (6) controls the induction heating means (2) and the cooling means (3) based on the temperature detected by the temperature sensor (5) electromagnetically shielded from the induction heating coil (2a) using parameters such as a wave number and a supply current applied to the induction heating means (2), a flow rate and another temperature of a coolant supplied to the cooling means (3) at an inlet, and a distance between the member to be machined (1) and the cooling plate. [12] Heating and cooling device (102) according to claim 5, wherein control means (6) controls the induction heating means (2) and the cooling means (3) on the basis of the temperature detected by the temperature sensor (5) which is electromagnetically shielded from the induction heating coil (2a), using parameters such as a further wave number and a further supply current applied to the induction heating means (2), a further flow rate and a still further temperature of a coolant supplied to the cooling means (3) at a further inlet, and a further distance between the element to be machined (1) and the cooling plate. [13] Heating and cooling device (102) according to claim 1, wherein the heating and cooling device (102) includes: an evacuation device (11) connected to the processing chamber (4); a reducing gas supply device (12) which introduces a reducing gas into the processing chamber (4); and an inert gas supply device (13) which introduces an inert gas into the processing chamber (4); wherein the control device (6) controls the evacuation device (11), the supply device (12) for reducing gas and the supply device (13) for inert gas. [14] The heating and cooling device (102) according to claim 13, wherein the heating and cooling device (102) includes a pressure gauge (19) for detecting an internal pressure of the processing chamber (4), wherein the control device (6) controls the evacuation device (11) so as to reduce the pressure of the processing chamber (4) and then receives the internal pressure of the processing chamber (4) detected by the pressure gauge (19), so that the control device (6) controls an output signal so as to convert the internal pressure into the maximum applied current based on parameters related to the wave number and the current applied to the induction heating device (2). [15] Heating and cooling device (102) according to claim 1, wherein the induction heating coil (2a) is preferably formed from one or a plurality of coils which have a vertically oriented elliptical shape in the longitudinal direction, wherein a constriction is arranged around the center thereof and they are preferably arranged parallel to the element (1) to be processed. [16] Heating and cooling device (102) according to claim 1, wherein two or more groups of the induction heating device (2) and the cooling device (3) are arranged in a processing chamber (4). [17] Heating and cooling device (102) according to claim 1, wherein the heating and cooling device (102) includes a pressing unit with which a tray is pressed against the cooling unit, wherein the tray on which the element to be processed (1) is placed is cooled when the tray is in contact with the cooling unit.

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