Pressurizing device and pressurizing method

Abstract

One embodiment of a pressure device according to the present invention comprises: a mounting plate on which a workpiece is placed; an upper die that presses the workpiece placed on the mounting plate from the upper side; a lower die that is preheated by a heating means and heats the workpiece while pressing it by clamping the mounting plate together with the upper die; a lower die that is precooled by a cooling means and cools the workpiece while pressing it by clamping the mounting plate together with the upper die; and a control device that controls the driving of the upper die and the lower die, wherein the control device switches the lower die contributing to the pressure of the workpiece into a heating lower die or a cooling lower die according to the progress of the pressure treatment of the workpiece, and additionally comprises an interposed pad interposed between the upper die and the workpiece, wherein the interposed pad comprises a flexible layer that is flexibly deformed according to the shape of the workpiece and interposed between the flexible layer and the workpiece, and It may include an insulating layer that insulates the space between the workpiece and the flexible layer.

Description

Technology Field

[0001] The present invention relates to a pressurizing device and a pressurizing method for heating a workpiece while simultaneously applying pressure in a plurality of pressurizing forms. Background Technology

[0002] Conventionally, a pressurizing device is known for heating a workpiece while clamping and pressing the workpiece with a plurality of pressurizing molds in order to heat and pressurize the workpiece. For example, Patent Documents 1 and 2 disclose a device that clamps and presses the workpiece with a lower mold and an upper mold, and heats the workpiece with a heater embedded in the mold. In such a pressurizing device, after the pressurization and heating of the workpiece are completed, the workpiece is cooled while maintaining the pressurized state. Then, when the workpiece is cooled to a predetermined temperature, the mold is removed from the workpiece, and the workpiece is ejected. Prior art literature

[0003] Japanese Patent Publication No. 2004-296746 Japanese Patent Publication No. 2007-896 The problem to be solved

[0004] Conventional pressurization devices provided heaters and refrigerant passages inside the mold to heat and cool the workpiece, heating or cooling the mold according to the progress of the processing. However, with this configuration, time was required to raise the mold to a predetermined temperature after cooling or to lower it to a predetermined temperature after heating, resulting in prolonged processing times for the workpiece. Furthermore, attempting to rapidly heat the mold using a heater made it prone to overshoot, where the mold temperature temporarily exceeded the set temperature, raising concerns that unexpectedly high heat would be applied to the workpiece.

[0005] Accordingly, the present invention aims to provide a pressurizing device and a pressurizing method capable of controlling the temperature of a workpiece more appropriately in a shorter period of time. means of solving the problem

[0006] The pressure device of the present invention is characterized by comprising: a mounting plate on which a workpiece is placed; an upper die that presses the workpiece placed on the mounting plate from the upper side; a lower die that is preheated by a heating means and heats the workpiece while pressing it by clamping the mounting plate together with the upper die; a lower die that is precooled by a cooling means and cools the workpiece while pressing it by clamping the mounting plate together with the upper die; and a control device that controls the operation of the mold, wherein the control device switches the lower die contributing to the pressure of the workpiece into a heating lower die or a cooling lower die according to the progress of the pressure treatment of the workpiece.

[0007] In a preferred embodiment, additionally, an interposing pad is provided between the mold and the workpiece, wherein the interposing pad comprises a flexible layer that is flexibly deformed according to the shape of the workpiece, and an insulating layer interposed between the flexible layer and the workpiece to provide insulation between the workpiece and the flexible layer.

[0008] In this case, it is preferable that the lower heating mold heats the workpiece to a temperature higher than the heat resistance temperature of the flexible layer.

[0009] In addition, in this case, it is preferable that the control device contacts the interposed pad with the workpiece to hold the workpiece with the interposed pad, and then performs heating and pressurizing of the workpiece by the lower heating die.

[0010] In another preferred embodiment, additionally, a side mold is provided that is positioned around the upper mold and comes into close contact with the mounting base to form a sealed space around the workpiece together with the upper mold and the mounting base, and a suction device is provided to suck air within the sealed space to create a vacuum around the workpiece, and the control device preferably drives the suction device to create a vacuum in the sealed space while simultaneously bringing the side mold into contact with the mounting base to form the sealed space prior to pressurizing the workpiece.

[0011] In another pressurizing method according to the present invention, the pressurizing method for pressurizing and heating a workpiece placed on a workpiece holder comprises: an upper die; a heating step of pressing the workpiece placed on the workpiece holder by means of a lower die heated in advance by a heating means, while simultaneously heating the workpiece with heat from the lower die heated in advance; and a cooling step of pressing the workpiece by means of a lower die cooled in advance by means of a cooling means, while simultaneously cooling the workpiece.

[0012] In addition, one embodiment of a pressure device according to the present invention comprises: a mounting plate on which a workpiece is placed; an upper die that presses the workpiece placed on the mounting plate from the upper side; a lower die that is preheated by a heating means and heats the workpiece while pressing it by clamping the mounting plate together with the upper die; a lower die that is precooled by a cooling means and cools the workpiece while pressing it by clamping the mounting plate together with the upper die; a control device that controls the driving of the upper die and the lower die, wherein the control device switches the lower die contributing to the pressure of the workpiece into a heating lower die or a cooling lower die according to the progress of the pressure treatment of the workpiece; additionally, an interposing pad is provided between the upper die and the workpiece, wherein the interposing pad comprises a flexible layer that is flexibly deformed according to the shape of the workpiece, and between the flexible layer and the workpiece It may also include an insulating layer that insulates the space between the workpiece and the flexible layer.

[0013] Here, the lower mold for heating can heat the workpiece to a temperature higher than the heat resistance temperature of the flexible layer.

[0014] Here, the control device can bring the interposed pad into contact with the workpiece and hold the workpiece with the interposed pad, and then perform heating and pressurizing of the workpiece by the lower heating mold.

[0015] Additionally, the device comprises a side type that is positioned around the upper die and forms a sealed space around the workpiece together with the upper die and the workpiece by adhering to the workpiece, and a suction device that sucks air within the sealed space to create a vacuum around the workpiece, and the control device may, prior to pressurizing the workpiece, bring the side type into contact with the workpiece to form the sealed space and simultaneously drive the suction device to create a vacuum in the sealed space.

[0016] In addition, one embodiment of the pressurizing method according to the present invention is a pressurizing method for pressurizing and heating a workpiece placed on a workpiece holder, comprising: a heating step of pressurizing the workpiece by clamping the workpiece holder with the upper die and the lower die heated by a heating means, thereby pressing the workpiece, and heating the workpiece with heat from the lower die heated by the upper die; and a cooling step of pressurizing the workpiece by clamping the workpiece holder with the upper die and the lower die cooled by a cooling means, thereby cooling the workpiece, wherein an interposed pad is interposed between the upper die and the workpiece, and the interposed pad may include a flexible layer that is flexibly deformed according to the shape of the workpiece, and an insulating layer interposed between the flexible layer and the workpiece to insulate the space between the workpiece and the flexible layer.

[0017] In addition, another embodiment of the pressure device according to the present invention comprises: a mounting plate on which a workpiece is placed; an upper die that presses the workpiece placed on the mounting plate from the upper side; a lower die that is preheated by a heating means and heats the workpiece while pressurizing it by clamping the mounting plate together with the upper die; a side die that is positioned around the upper die and forms a sealed space around the workpiece together with the upper die and the mounting plate by being in close contact with the mounting plate; a suction device that sucks air within the sealed space to create a vacuum around the workpiece; a lower die that is precooled by a cooling means and cools the workpiece while pressurizing it by clamping the mounting plate together with the upper die; and a control device that controls the operation of the upper die and the lower die, wherein, depending on the progress of the pressure treatment of the workpiece, the lower die contributing to the pressure of the workpiece is switched to a heating lower die or a cooling lower die. A control device is provided, and prior to pressurizing the workpiece, the control device contacts the side mold with the mounting base to form the sealed space, and simultaneously drives the suction device to bring the sealed space into a vacuum state, and the upper unit including the upper mold and the side mold can descend and ascend together with the mounting base while vacuum adsorbing the mounting base. Effects of the invention

[0018] According to the present invention, depending on the progress of the pressure treatment, the lower mold contributing to the pressure of the workpiece is switched to a preheated lower mold for heating or a precooled lower mold for cooling, thereby significantly reducing the time required for heating or cooling and also allowing the temperature of the workpiece to be appropriately controlled. Brief explanation of the drawing

[0019] FIG. 1 is a diagram illustrating the principle of pressurizing a workpiece in a pressurizing device of the present embodiment. FIG. 2 is a drawing showing the configuration of a pressurizing device of the present embodiment. Figure 3 is a diagram showing the process of pressurization treatment in a pressurization device. Figure 4 is a diagram showing the process of pressurization treatment in a pressurization device. Figure 5 is a diagram showing the process of pressurization treatment in a pressurization device. Figure 6 is a diagram showing the process of pressurization treatment in a pressurization device. Figure 7 is a diagram showing the process of pressurization treatment in a pressurization device. Figure 8 is a graph showing an example of changes in the pressure of the surrounding environment of the workpiece, the temperature of the workpiece, and the load applied to the workpiece during the pressurization process. FIG. 9 is a diagram showing the process of pressurization treatment in a pressurization device of the second embodiment. FIG. 10 is a diagram showing the process of pressurization treatment in a pressurization device of a second embodiment. FIG. 11 is a diagram showing the process of pressurization treatment in a pressurization device of the second embodiment. FIG. 12 is a diagram showing the process of pressurization treatment in a pressurization device of the second embodiment. Specific details for implementing the invention

[0020] Hereinafter, a pressurizing device (10) which is an embodiment of the present invention will be described with reference to the drawings. First, the principle of pressurization in the pressurizing device (10) of the present embodiment will be described with reference to FIG. 1. In the present embodiment, the workpiece (100) includes a plurality of electronic components (112) that are bonded using a thermosetting adhesive. For example, as shown in FIG. 1, the workpiece (100) includes a substrate (110), electronic components (112), such as circuit elements, disposed on the substrate (110), and a sheet-shaped adhesive (114) interposed between the substrate (110) and the electronic components (112). A wiring (111) is formed in a predetermined pattern on the surface of the substrate (110). On the surface of the electronic components (112) facing the substrate (110) (the lower surface in the drawings), a protrusion called a bump (113) that serves as an electrical contact is provided. The adhesive (114) is made of a thermosetting adhesive and is placed between the electronic component (112) and the substrate (110). In the initial stage before pressurization and heating are initiated, the adhesive (114) is in the form of a sheet having a predetermined shape. When the adhesive (114) exceeds a predetermined glass transition temperature (Tg), it softens and becomes fluid, and then, when the temperature rises further and exceeds a predetermined curing temperature (Tc), it hardens irreversibly.

[0021] When bonding an electronic component (112) to a substrate (110), the workpiece (100) is pressed by clamping it with an upper mold and a lower mold, and heated. By heating, the adhesive (114) softens by exceeding the glass transition temperature (Tg). Furthermore, as heating continues, the adhesive (114) reaches the curing temperature (Tc) and hardens. During the period from when the adhesive (114) softens until it hardens, the workpiece (100) is continuously pressed, thereby compressing the portion of the adhesive (114) that is sandwiched between the wiring (111) and the bump (113), so that the connection between the bump (113) and the wiring (111) becomes electrically connected.

[0022] Here, in order to apply pressure evenly to the electronic component (112) and the adhesive (114) from the surrounding area (upward and sideward in the drawing), in this embodiment, an interposed pad (24) is provided in the upper mold (20). The interposed pad (24) has flexibility that deforms according to the shape of the workpiece (100). When the workpiece (100) is pressed through such an interposed pad (24), as shown in Fig. 1 (c), the interposed pad (24) moves inward toward the side of the electronic component (112) or the adhesive (114). Then, the pressure from the upper mold (20) is transmitted through the interposed pad (24) not only upward but also sideward to the electronic component (112) and the adhesive (114).

[0023] After the adhesive (114) has cured, the workpiece (100) is cooled while maintaining a state of pressure on the workpiece (100) to prevent warping of the workpiece (100) caused by the difference in thermal expansion between the front and back surfaces. Then, when the temperature of the workpiece (100) drops to a temperature at which it can be removed, the pressure is released and the workpiece (100) is removed from the mold.

[0024] Next, a pressurizing device (10) that realizes such pressurization will be described. FIG. 2 is a diagram showing the configuration of the pressurizing device (10) of the present embodiment. The pressurizing device (10) is equipped with a mounting plate (12) on which a workpiece (100) is mounted, an upper unit (14) positioned on the upper side of the mounting plate (12), a lower unit (16) positioned on the lower side of the mounting plate (12), and a control unit (18) that controls the operation of these.

[0025] The mounting platform (12) is a platform on which a workpiece (100) is mounted. The mounting platform (12) is not particularly limited in its configuration as long as it can withstand the pressure applied from the upper unit (14) and the lower unit (16) and the heat applied from the lower mold (50) for heating described later. However, in order to shorten the processing time, it is preferable that the mounting platform (12) be made of a high thermal material that allows heat from the lower mold (50) for heating to be transferred quickly. As for the high thermal material, for example, copper (400 W / mK) or an alloy containing copper, such as STC (registered trademark, 630 W / mK) manufactured by Moriya Cutlery Laboratory Co., Ltd. or Comporoid (product name, 1700 W / mK) manufactured by Thermographic Tissue Co., Ltd.

[0026] In addition, as will be explained in detail later, in this embodiment, the workpiece (100) is placed in a vacuum state. The mounting plate (12) preferably has a strength sufficient to withstand thrust caused by this vacuum, and preferably has a thickness of 5 mm or more, more preferably 8 mm or more, and more preferably 10 mm or more. However, if the thickness is excessively large, the volume of the mounting plate (12), and furthermore, the heat capacity, increases, so the amount of heat required for heating or the amount of cooling required for cooling increases, and the time required for heating and cooling increases. Therefore, it is preferable for the mounting plate (12) to have a thickness of, for example, 10 mm to 20 mm, such that strength is obtained to withstand thrust caused by the vacuum while suppressing the heat capacity.

[0027] The upper unit (14) is formed on the upper side of the mounting base (12) and comprises a base member (22), an upper die (20) that presses the workpiece (100), an interposed pad (24) that is interposed between the upper die (20) and the workpiece (100), a frame body (26) that supports the interposed pad (24), and a side type (28) that forms a sealed space by being in close contact with the mounting base (12).

[0028] The base member (22) is capable of being raised by a lifting mechanism not shown in the drawing, and as the base member (22) is raised, the upper mold (20), the side mold (28), and the frame body (26) are raised. The raising of the base member (22) is controlled by a control unit (18). The upper mold (20) is a mold for pressing the workpiece (100) from the upper side and is placed directly above the workpiece (100). The upper mold (20) is fixed to the base member (22) and is raised in conjunction with the base member (22). A refrigerant flow path (30a) through which refrigerant flows is formed inside the upper mold (20). A cooling device not shown in the drawing circulates the refrigerant so that it passes through the refrigerant flow path (30a). That is, the cooling device supplies the refrigerant to the refrigerant flow path (30a). The refrigerant absorbs heat from the upper mold (20) while flowing through the refrigerant flow path (30a) and its temperature rises. The cooling device recovers the refrigerant discharged from the refrigerant flow path (30a), cools it, and then sends the cooled refrigerant back to the refrigerant flow path (30a). Also, as is evident from FIG. 2, the upper mold (20) is not provided with a heating means, and the upper mold (20) is not heated, and only cooling is performed.

[0029] A frame body (26) that supports an interposed pad (24) is provided around the upper mold (20). The frame body (26) is mounted on a base member (22) via a spring member (32) and is configured to move slightly up and down relative to the upper mold (20). The interposed pad (24) is an elastic body interposed between the workpiece (100) and the upper mold (20), and is equipped with a flexible layer (34) that is flexibly deformed according to the shape of the workpiece (100), and an insulating layer (36) interposed between the flexible layer (34) and the workpiece (100). The flexible layer (34) is intended to evenly transmit the pressure of the upper mold (20) and is made of a flexible material such as rubber. This flexible layer (34) may have a single-layer structure, but may also have multiple layers. For example, the flexible layer (34) may have a two-layer structure comprising a fluid flexible layer made of a material that has high fluidity and low rebound elasticity, and a porous flexible layer made of a porous material such as a silicone sponge or a fluorine sponge. As for the material of the fluid flexible layer, for example, the high-dumping thermal conductive gel sheet "αGEL" (trademark) made by Geltech Co., Ltd., the thermoplastic elastomer made by Riken Technos Co., Ltd., and the ultra-soft elastomer "Frenzel" (product name) made by Kinugawa Rubber Industry Co., Ltd. may be used.

[0030] The insulating layer (36) is a layer interposed between the workpiece (100) and the flexible layer (34), and prevents heat from the workpiece (100) from being transferred to the flexible layer (34). This insulating layer (36) is made of a fiber material with low thermal conductivity, such as glass wool, ceramic wool, or heat-resistant felt. It is desirable for the insulating layer (36) to be thick to ensure thermal insulation. On the other hand, the insulating layer (36) must also have flexibility to deform according to the shape of the workpiece (100) in order to uniformly transfer pressure from the mold (20) to the workpiece (100), so it cannot be made excessively thick. For this reason, the thickness of the insulating layer (36) is a thickness that can achieve both appropriate thermal insulation and flexibility, for example, 2 mm to 10 mm, preferably 3 mm to 6 mm.

[0031] In addition, if the insulation layer (36) is brought into direct contact with the workpiece (100), the insulation layer (36) adheres to the workpiece (100), making it difficult to separate the two. Therefore, when pressing the workpiece (100), an intermediate sheet (38) for preventing adhesion is additionally placed between the insulation layer (36) and the workpiece (100). The intermediate sheet (38) is a thin sheet-shaped member having flexibility and is made of, for example, a fluoropolymer such as polytetrafluoroethylene (PTFE) or polyimide. In principle, this intermediate sheet (38) is discarded and replaced after one to several uses.

[0032] The side type (28) is positioned around the upper type (20) and is mounted on the base member (22) via an air cylinder (40). By adhering to the upper surface of the mounting base (12), the side type (28) forms a sealed space surrounded by the side type (28), the mounting base (12), the upper type (20), and the frame body (26). To form this sealed space, a seal member (28a) is provided on the bottom surface of the side type (28). Additionally, the side type (28) is made to be able to move up and down relative to the upper type (20) by driving the air cylinder (40). A refrigerant passage (30b) through which refrigerant flows is also formed inside the side type (28), and the side type (28) is cooled by circulating the refrigerant so that the cooling device passes through the refrigerant passage (30b).

[0033] In addition, a suction hole (42) penetrating in the horizontal direction is also formed in the side type (28). This suction hole (42) is connected to a suction pump (44). Then, when the side type (28) is pressed against the mounting base (12) to form a sealed space, and the suction pump (44) is driven, the air in the sealed space is sucked in, and the sealed space becomes a vacuum. The operation of such a suction pump (44) or air cylinder (40) is controlled by the control unit (18). In addition, in this embodiment, the side type (28) is mounted on the base member (22) via the air cylinder (40), but other configurations may be used as long as they allow the side type (28) to be raised or lowered relative to the upper type (20). For example, a hydraulic cylinder or an electric cylinder may be used instead of the air cylinder (40).

[0034] The lower unit (16) is equipped with a lower mold for heating (50), a lower mold for cooling (52), and a switching mechanism (not shown). The switching mechanism is a mechanism for distinguishing between the lower mold for heating (50) and the lower mold for cooling (52) by inserting the lower mold for cooling (52) into the upper part of the lower mold for heating (50). The lower mold for heating (50) is a mold for heating and pressurizing a workpiece (100), and a heater (54) that functions as a heating means is provided inside it. The heater (54) is not particularly limited as long as it can heat the lower mold for heating (50) to a predetermined processing temperature (Tp) and withstand a specified press load (Pp). In this embodiment, as the heater (54), a cartridge heater is used, in which a heating wire (nichrome wire) is wound around a rod-shaped ceramic and inserted into a heat-resistant pipe to form a cartridge. The control unit (18) controls the operation of the heater (54) to maintain the heating mold (50) at a predetermined processing temperature (Tp). Here, the processing temperature (Tp) is a temperature at which the workpiece (100), particularly the thermosetting adhesive (114) constituting part of the workpiece (100), can be heated to a temperature higher than the curing temperature (Tc) of the adhesive (114). For example, when the curing temperature (Tc) is 150 to 200 degrees, the processing temperature (Tp) is set to a temperature sufficiently higher than the curing temperature (Tc), for example, 300 degrees.

[0035] A first insulating member (56) is provided around the lower heating mold (50), preventing heat from the heater (54) from leaking laterally. Additionally, a second insulating member (58) is provided below the heater (54), preventing heat from the heater (54) from leaking downwards. The lower heating mold (50) is divided into upper and lower sections by the second insulating member (58), and a refrigerant passage (30d) through which refrigerant flows is formed below the second insulating member (58). The refrigerant is circulated by a cooling device to pass through the refrigerant passage (30d).

[0036] The cooling lower mold (52) is a mold for cooling and pressurizing a workpiece (100), and a refrigerant flow path (30e) through which a refrigerant flows is formed inside it. The refrigerant is circulated by a cooling device to pass through the refrigerant flow path (30e). In addition, an insulating member (60) is provided on the bottom surface of the cooling lower mold (52). By providing this insulating member (60), heat transfer from the heating lower mold (50) is prevented when the cooling lower mold (52) is placed directly above the heating lower mold (50).

[0037] The switching mechanism moves the cooling lower die (52) according to the progress of the processing. Specifically, the switching mechanism has a horizontal movement mechanism that moves the cooling lower die (52) horizontally. The horizontal movement mechanism moves the cooling lower die (52) between a position directly above the heating lower die (50) and a position horizontally offset from the heating lower die (50). In addition, the pressurizing device (10) is provided with a lifting mechanism that raises the upper unit (14), and lowers the upper unit (14) toward the lower unit (16) to press the workpiece (12) firmly against the heating lower die (50) or the cooling lower die (52) located above the heating lower die (50), thereby pressurizing the workpiece (100). That is, in this embodiment, when the cooling lower mold (52) is positioned above the heating lower mold (50), the workpiece (100) can be cooled and pressurized by lowering the upper unit (14), and when the cooling lower mold (52) is not present above the heating lower mold (50), the workpiece (100) can be heated and pressurized by lowering the upper unit (14). In another aspect, in this embodiment, the execution and release of pressurization are controlled by raising and lowering the upper unit (14) with a lifting mechanism, and the lower mold contributing to pressurization can be switched to the heating lower mold (50) or the cooling lower mold (52) by moving the cooling lower mold (52) horizontally with a horizontal movement mechanism. The operation of such a lifting mechanism and a horizontal movement mechanism is controlled by a control unit (18).

[0038] Next, the pressure treatment of the workpiece (100) in the pressure device (10) will be explained with reference to FIGS. 3 to 7. When the workpiece (100) is pressured, the lower mold (50) for heating is heated in advance by a heater (54) to a predetermined treatment temperature (Tp). In addition, the upper mold (20), the side mold (28), and the lower mold (52) for cooling are cooled using a refrigerant and are kept at a temperature sufficiently lower than the glass transition temperature (Tg) of the adhesive (114) provided on the workpiece (100), for example, room temperature.

[0039] When the workpiece (100) is placed on the mounting plate (12) and the mounting plate (12) is returned directly below the upper die (20), the control unit (18) first lowers the upper unit (14) or raises the mounting plate (12) as shown in FIG. 3, thereby bringing the bottom surface of the side die (28) into close contact with the mounting plate (12). At this time, so that the upper die (20) or the mounting pad (24) does not come into contact with the workpiece (100), the control unit (18) applies air pressure to the air cylinder (40) to extend it, thereby keeping the side die (28) in a state where it protrudes downward from the upper die (20), etc. Also, at this time, the lower die for heating (50) and the lower die for cooling (52) are both separated from the mounting plate (12). Therefore, in this state, no pressure is applied to the workpiece (100).

[0040] By pressing the bottom surface of the side type (28) against the mounting base (12), a sealed space is formed that is surrounded by the side type (28), the upper type (20), the frame body (26), and the mounting base (12). When this state is reached, the control unit (18) drives the suction pump (44) to suck in the air inside the sealed space, thereby making the sealed space a vacuum. Accordingly, the air surrounding the workpiece (100) is removed. By removing the air surrounding the adhesive (114) before the adhesive (114) softens, air mixing into the interior of the adhesive (114) after softening is effectively prevented.

[0041] When the vacuum suction of the sealed space is completed, the control unit (18) releases the pressure of the air cylinder (40) to allow the air cylinder (40) to contract. When the air cylinder (40) is contracted, the upper mold (20) and the side mold (28) move relative to the workpiece (100) and the mounting base (12) by the vacuum pressure (by the pressure difference between the sealed space and the external space). Finally, the interposed pad (24) comes into contact with the workpiece (100), and the workpiece (100) is pre-pressed by a load (Pb) according to the vacuum pressure. The load (Pb) of this pre-pressure is sufficiently lower than the press load (Pp) applied in the main pressure described later. Also, as is evident from the description above and from FIG. 4, this pre-pressure is performed with the mounting base (12) and the lower mold (50) for heating separated. In other words, the pre-pressure is performed when the workpiece (100) is not heated and the adhesive (114) is not softened. By performing this pre-pressure, the interposing pad (24) is deformed according to the surface shape of the workpiece (100), and moves around the workpiece (100), particularly around the adhesive (114) before softening, to hold the workpiece (100).

[0042] Subsequently, when the insert pad (24) adheres to the workpiece (100) by means of preliminary pressure, the control unit (18) lowers the upper unit (14) to which the mounting base (12) is vacuum-adsorbed, as shown in FIG. 5, and performs the main pressure by applying pressure to the mounting base (12) from the lower side with the heating lower die (50). In the main pressure, the workpiece (100) is clamped between the upper die (20) and the heating lower die (50) and is pressed with a specified press load (Pp). In addition, as described above, the heating lower die (50) is preheated to a predetermined processing temperature (Tp). The heat from this heating lower die (50) is transferred to the workpiece (100) through the mounting base (12), which has excellent heat transfer properties. That is, in this pressurization, the workpiece (100) is pressed with a specified press load (Pp) and heated to a specified processing temperature (Tp). By performing this pressurization for a specified time, the thermosetting adhesive (114) provided on the workpiece (100) reaches a glass transition temperature (Tg) and softens, then reaches a curing temperature (Tc) and hardens. Accordingly, the electronic component (112) and the substrate (110) are bonded. Also, at this time, the heat from the lower mold (50) for heating is transferred to the interposing pad (24) through the mounting base (12) and the workpiece (100). However, since an insulating layer (36) is provided at the bottom of the interposing pad (24), heat is difficult to transfer to the flexible layer (34), so the flexible layer (34) or the upper mold (20) located thereon is prevented from becoming excessively hot.

[0043] If sufficient time is allowed to execute the pressurization, the control unit (18) raises the upper unit (14) as shown in FIG. 6 to separate the lower heating mold (50) from the mounting stand (12). If sufficient space can be formed between the lower heating mold (50) and the mounting stand (12), the control unit (18) places the lower cooling mold (52) between the mounting stand (12) and the lower heating mold (50) as shown in FIG. 7. Then, in this state, the upper unit (14) is lowered together with the mounting stand (12) to pressurize the workpiece (100) with a specified cooling load (Pc). At this time, since the lower cooling mold (52) is pre-cooled by a refrigerant, the workpiece (100) can be cooled quickly. Additionally, during the cooling period, the workpiece (100) is clamped between the cooling lower die (52) and the upper die (20) and pressurized, so warping caused by the difference in thermal expansion is effectively prevented. Also, the load (Pc) during cooling can be smaller than the press load (Pp) as long as it prevents deformation of the workpiece (100). When the workpiece (100) can be cooled to a temperature at which it can be ejected (e.g., room temperature), the control unit (18) raises the upper unit (14) together with the mounting base (12) and releases the pressurization. Additionally, the control unit (18) applies pressure to the air cylinder (40) and extends the air cylinder (40) to raise the upper die (20) and separate the interposed pad (24) from the workpiece (100). Additionally, the suction hole (42) is released to the atmosphere, and the sealed space is made to atmospheric pressure. And finally, by further raising the upper unit (14) to separate the upper mold (20) unit from the storage stand (12), the storage stand (12) is returned to a predetermined outgoing location (not shown).

[0044] FIG. 8 is a graph showing an example of changes in the pressure of the surrounding environment of the workpiece (100), the temperature of the workpiece (100), and the load applied to the workpiece (100) during the execution of the pressurization process. As is evident from the description so far, at the start of the pressurization process (time t0), the pressure of the surrounding environment of the workpiece (100) is atmospheric pressure (Pa). Also, at time t0, since heating or pressurization of the workpiece (100) has not yet started, the temperature of the workpiece (100) is room temperature (Tn) and the pressurization force is zero.

[0045] Subsequently, vacuum suction is initiated at time t1, and after the vacuum suction is completed, the pressure of the air cylinder (40) is released. At time t2, a load (Pb) corresponding to the vacuum pressure (Pv) is applied to the workpiece (100), and it is pre-pressed. Then, at time t3, the main pressurization is initiated by applying pressure to the mounting base (12) with the heating lower mold (50) that has finished heating. When the main pressurization is initiated, the temperature of the workpiece (100) rises rapidly and reaches the specified processing temperature (Tp) in a relatively short time. This processing temperature (Tp) is higher than the glass transition temperature (Tg) of the adhesive (114) provided on the workpiece (100) or the curing temperature (Tc) of the adhesive. Accordingly, the workpiece (100) reaches a glass transition temperature (Tg) and softens during the process of reaching a processing temperature (Tp), and then reaches a hardening temperature (Tc) and hardens.

[0046] Additionally, by applying pressure with a heating lower mold (50), at time t4, the workpiece (100) is pressed with a predetermined press load (Pp). This press load (Pp) is of a size sufficient to obtain electrical conductivity between the bump (113) of the electronic component (112) and the wiring of the substrate (110), for example, 20 tons. After that, at time t5, this pressing is terminated. That is, at time t5, the control unit (18) raises the upper unit (14) to release the pressure on the workpiece (100).

[0047] When the upper unit (14) is raised, the pressure applied to the workpiece (100) decreases rapidly. Meanwhile, in natural cooling, the temperature of the workpiece (100) is difficult to lower, and the workpiece (100) remains at the processing temperature (Tp). Therefore, in order to cool the workpiece (100), the control unit (18) pressurizes the workpiece (100) with the cooling lower mold (52) instead of the heating lower mold (50) to cool it. At time t6, when the cooling lower mold (52) comes into contact with the mounting base (12), the temperature of the workpiece (100) decreases rapidly. In addition, as the upper unit (14) is lowered, the pressure applied to the workpiece (100) also increases, and deformation such as bending of the workpiece (100) is effectively prevented. The cooling load (Pc) applied at this time is, for example, about 10 tons.

[0048] When the workpiece (100) can be cooled to room temperature, the control unit (18) raises the upper unit (14) to release the pressure on the workpiece (100). After that, the surroundings of the workpiece (100) are released to atmospheric pressure. Then, at time t8, when the surroundings of the workpiece (100) return to atmospheric pressure, the upper unit (14) is moved away from the workpiece (100), and the workpiece (100) is returned to the discharge position along with the mounting table (12).

[0049] As is evident from the above description, in this embodiment, the lower mold contributing to the pressurization of the workpiece (100) is converted into a preheated lower mold (50) and a precooled lower mold (52). The reason for this configuration will be explained in comparison with the prior art.

[0050] In a conventional pressurizing device (10), a workpiece (100) is clamped between an upper mold (20) and a lower mold, and the workpiece (100) is heated or cooled as needed. In a conventional heating device, both a heating means and a cooling means are provided inside the lower mold to heat and cool the workpiece (100), and the lower mold is heated and cooled as needed. In this case, time is required to heat the cooled lower mold to a predetermined processing temperature (Tp), and time is required to cool the heated lower mold to a predetermined cooling temperature. As a result, the conventional pressurizing device (10) caused the processing time to be prolonged. In particular, in the pressurizing device (10), in order to withstand high pressure, the lower mold must have a thick thickness and a shape with a large heat capacity. Heating and cooling such a large lower mold took time.

[0051] Of course, the time required for heating can be shortened by using a heater with high heating capacity. However, such a heater is expensive and causes an increase in costs. In addition, if one attempts to raise the lower mold, which has been cooled once, to the heating temperature in a short period of time, an overshoot is likely to occur during the raising process, exceeding the desired processing temperature (Tp). As a result, there was a risk that the workpiece (100) would be overheated, even if only temporarily.

[0052] In this embodiment, as described above, a preheated lower mold (50) and a precooled lower mold (52) are switched according to the progress of the process. As a result, time for heating or cooling the lower mold is unnecessary, allowing the workpiece (100) to be heated and cooled quickly. That is, as explained with reference to FIG. 8, in this embodiment, when the heating lower mold (50) comes into contact with the mounting table (12) (refer to time t3 in FIG. 8), the workpiece (100) quickly rises in temperature, and when the cooling lower mold (52) comes into contact with the mounting table (12) (refer to time t6 in FIG. 8), the workpiece (100) quickly lowers in temperature. In other words, according to this embodiment, time for heating or cooling the lower mold to a desired temperature is unnecessary. As a result, the time required for pressure treatment can be significantly reduced.

[0053] In addition, by dividing the lower mold into heating and cooling modes, energy loss can be reduced and steam generation can also be reduced. That is, in a conventional pressurizing device (10) that heats and cools a single lower mold, it is necessary to heat and cool a lower mold with a large heat capacity, so energy loss was significant. Furthermore, if a liquid such as water is flowed as a refrigerant to cool the lower mold after heating it, the liquid turns into steam, causing a rise in pressure within the refrigerant flow path. To prevent such problems, it is necessary to flow cooling air before supplying the liquid, or to provide a separate buffer to temporarily store and cool the steam generated after supplying the liquid, which has caused complexity in the configuration. In this embodiment, since there is no need to flow a refrigerant inside the high-temperature component, steam generation is eliminated, and the configuration can be simplified.

[0054] In addition, in this embodiment, the workpiece (100) is heated only from the lower side and not from the upper side. In other words, in this embodiment, the upper mold (20) is not provided with a heating means. Accordingly, it is possible to heat the workpiece (100) to a higher temperature than conventional methods without raising the temperature of the interposed pad (24).

[0055] That is, in conventional pressurizing devices (10), heating means were provided in the upper mold (20) as well as the lower mold to enable rapid heating. In this case, while the workpiece (100) can be heated rapidly, the interposed pad (24) interposed between the upper mold (20) and the workpiece (100) is also heated. Here, the interposed pad (24) of the present embodiment has an insulating layer (36), whereas the conventional interposed pad (24) does not have an insulating layer (36) and is mainly composed of a flexible layer in which a silicone-based organic material is the main component. The heat resistance temperature of such a flexible layer (34) is often less than 200 degrees. Meanwhile, recently, the curing temperature (Tc) of the adhesive (114) provided on the workpiece (100) has increased and is often between 150 and 300 degrees. That is, in order to cure the adhesive (114) and bond the electronic component (112) to the substrate (110), it is necessary to heat the workpiece (100) to 150 to 300 degrees.

[0056] When attempting to heat a workpiece (100) to 150 to 300 degrees using a heating means provided in the upper mold (20), the interposed pad (24) (flexible layer (34)) provided between the upper mold (20) and the workpiece (100) is also heated. In this case, there was a risk that the interposed pad (24) would exceed its heat resistance temperature and be damaged. That is, in a conventional pressurizing device (10) provided with a heating means in the upper mold (20), there was a risk of damage to the interposed pad (24). For this reason, in a conventional pressurizing device (10) provided with a heating means in the upper mold (20), the workpiece (100) could not be heated to a temperature higher than the heat resistance temperature of the interposed pad (24) (flexible layer (34)).

[0057] Meanwhile, in this embodiment, as described above, the heating means is provided only in the lower mold (50) for heating, and the upper mold (20) is not provided with a heating means. Therefore, the flexible layer (34) with low heat resistance is not heated from the upper mold (20). In addition, in this embodiment, an insulating layer (36) is provided between the flexible layer (34) with low heat resistance and the workpiece (100) heated to a high temperature. Furthermore, the upper mold (20) is maintained at a constant temperature by allowing a refrigerant to flow through the refrigerant path (30a). As a result, heat transfer to the flexible layer (34) is effectively prevented, thereby effectively preventing the temperature rise of the flexible layer (34) and, furthermore, thermal damage. In another view, according to this embodiment, the workpiece (100) can be heated to a temperature higher than the heat resistance temperature of the flexible layer (34), thereby expanding the range of workpieces (100) that can be handled.

[0058] In addition, as is evident from the description above, in this embodiment, the surrounding environment of the workpiece (100) is vacuum-suctioned prior to heating the workpiece (100). Accordingly, air mixing, where air remains inside the adhesive (114) after heating and pressurization, can be prevented. Here, it is preferable to perform this vacuum suction before the adhesive melts, that is, before the adhesive (114) reaches the glass transition temperature (Tg). In the case of a conventional pressurization device (10) provided with a heating means in the upper mold (20), there is a problem in that the adhesive (114) melts and cannot be properly exhausted because the upper mold (20) at a high temperature approaches the workpiece (100) during vacuum suction. Of course, if the heating of the upper mold (20) is stopped during vacuum suction, this problem can be avoided, but in this case, it is necessary to heat the upper mold (20) after vacuum suction, which has the problem of prolonging the time required for processing.

[0059] In addition, in this embodiment, after vacuum suction and prior to heating of the workpiece (100), a preliminary press is performed by applying a preliminary load (Pb) lower than the press load (Pp) to the upper mold (20) and the interposing pad (24). By applying a preliminary press before heating, the workpiece (100) is held by the interposing pad (24). As a result, even if the adhesive (114) melts, the movement of the electronic component (112) is restricted by the interposing pad (24), effectively preventing misalignment of the electronic component (112). That is, in the conventional press device (10), the press and heating of the workpiece (100) were performed without performing a preliminary press. Because of this, there was a concern that the adhesive (114) would reach the glass transition temperature (Tg) and soften before the workpiece (100) was sufficiently held by the interposing pad (24). If the adhesive (114) softens while the workpiece is not held by the interposing pad (24), the electronic component (112) can move relatively freely, which causes misalignment of the electronic component (112). Meanwhile, in the present embodiment, the workpiece (100) is pre-pressed with an unheated upper mold (20) and an interposing pad (24), and after the workpiece (100) is held by the interposing pad (24), the workpiece (100) is heated. Because of this, even if the adhesive softens due to heating, the movement of the electronic component (112) is restricted, and misalignment of the electronic component (112) can be effectively prevented.

[0060] Next, a second embodiment will be described with reference to FIGS. 9 to 12. FIGS. 9 to 12 are drawings showing the flow of the pressurization process in the second embodiment. The second embodiment differs from the first embodiment in that both the heating lower die (50) and the cooling lower die (52) can move horizontally. FIG. 9 shows the start of the pressurization process in the second embodiment. As shown in FIG. 9, in this case, the cooling lower die (52) is positioned horizontally offset from the upper die (20), and the heating lower die (50) is positioned below the upper die (20). In this state, the mounting plate (12) on which the workpiece (100) is placed is conveyed over the cooling lower die (52). In this case, since the lower cooling mold (52) is positioned horizontally offset from the upper mold (20), a large space can be secured on the upper side of the lower cooling mold (52), thereby sufficiently securing a space for transporting the mounting stand (12) (e.g., a space for installing a mechanism for transporting the mounting stand (12)).

[0061] When the mounting base (12) is returned to the lower cooling mold (52), the control unit (18) subsequently moves the lower heating mold (50) to a position offset horizontally from the upper mold (20), as shown in FIG. 10. At the same time, the control unit (18) moves the lower cooling mold (52) horizontally to a position directly below the upper mold (20). After that, the upper unit (14) is lowered so that the bottom surface of the side mold (28) is in close contact with the upper surface of the mounting base (12). After that, as in the first embodiment, the sealed space surrounding the workpiece (100) is vacuum-suctioned, and the workpiece is pre-pressed with a pre-load (Pb) using the differential pressure between the sealed space and the external space. When the preliminary pressurization is completed, the control unit (18) again moves the cooling lower die (52) to a position offset horizontally from the upper die (20), and moves the heating lower die (50) to a position directly below the upper die (20). Then, as shown in FIG. 11, the lower die (50) presses the workpiece (12) and performs the main pressurization, which heats the workpiece (100) while pressing it with a specified press load (Pp). When the main pressurization is completed, as shown in FIG. 12, the heating lower die (50) and the cooling lower die (52) are switched, and the workpiece (100) is cooled while pressing it with the cooling lower die (52). Then, when the cooling of the workpiece (100) is completed, the upper unit (14) is raised to separate the upper unit (14) from the mounting base (12), and the cooling lower die (52) on which the mounting base (12) is mounted is moved horizontally. After that, the mounting base (12) is returned to a predetermined discharge position.

[0062] As is evident from the above description and from FIGS. 10, FIGS. 12, etc., according to the second embodiment, since the heating lower mold (50) and the cooling lower mold (52) are not arranged vertically, heat transfer between the two lower molds (50, 52) is prevented. As a result, it becomes easy to maintain each lower mold (50, 52) at a specified temperature.

[0063] In addition, in the second embodiment, just like in the first embodiment, the time required for heating or cooling, and furthermore, the time for pressurization treatment, can be significantly reduced. Also, since vacuum suction and pre-pressurization are performed before the adhesive (114) softens, air ingress and misalignment of parts can be prevented more reliably.

[0064] Furthermore, the configuration described so far is merely an example, and other configurations may be appropriately modified as long as the lower mold contributing to the pressurization can be switched between a heating lower mold (50) and a cooling lower mold (52). For example, in this embodiment, vacuum suction or pre-pressurization is performed before the main pressurization, but in some cases, these may be omitted. Also, in this embodiment, a flexible layer (34) and an insulating layer (36) are provided in the interposed pad (24), but if the flexible layer (34) can be maintained below the heat resistance temperature, the insulating layer (36) may be omitted. Additionally, in the description so far, the upper unit (14) was raised to switch the execution / release of the pressurization, but instead of the upper unit (14), or in addition, the lower unit (16) may be raised to switch the execution / release of the pressurization. In addition, the configuration of various driving mechanisms, cooling means, and heating means may be changed to other known configurations. Explanation of the symbols

[0065] 10 Pressurizing device, 12 Mounting base, 14 Upper unit, 16 Lower unit, 18 Control unit, 20 Upper die, 22 Base member, 24 Insert pad, 26 Frame body, 28 Side type, 30 Refrigerant flow path, 32 Spring member, 34 Flexible layer, 36 Insulation layer, 38 Intermediate sheet, 40 Air cylinder, 42 Suction hole, 44 Suction pump, 50 Lower die for heating, 52 Lower die for cooling, 54 Heater, 56, 58, 60 Insulation member, 100 Workpiece, 110 Substrate, 111 Wiring, 112 Electronic component, 113 Bump, 114 Adhesive

Claims

Claim 1 A workpiece holder on which a workpiece is placed; an upper die that presses the workpiece placed on the holder from the upper side; a lower die that is preheated by a heating means and heats the workpiece while pressing it by clamping the holder together with the upper die; a lower die that is precooled by a cooling means and cools the workpiece while pressing it by clamping the holder together with the upper die; a control device that controls the operation of the upper die and the lower die, and switches the lower die contributing to the pressurization of the workpiece into a heating lower die or a cooling lower die depending on the progress of the pressurization process of the workpiece; an interposed pad placed between the upper die and the workpiece; a side die disposed around the upper die and forms a sealed space around the workpiece together with the upper die and the holder by adhering to the holder; and air within the sealed space is sucked in to the workpiece A pressurizing device comprising a suction device that creates a vacuum around the area, wherein the interposed pad includes a flexible layer that is flexibly deformed according to the shape of the workpiece, and an insulating layer interposed between the flexible layer and the workpiece to insulate the space between the workpiece and the flexible layer, wherein an intermediate sheet for preventing adhesion is disposed between the insulating layer and the workpiece, and wherein the control device, prior to pressurizing the workpiece, directly contacts a seal member disposed on the side-type bottom surface with the mounting plate to form the sealed space, and simultaneously drives the suction device to create a vacuum in the sealed space. Claim 2 A pressurizing device according to claim 1, wherein the lower heating mold heats the workpiece to a temperature higher than the heat resistance temperature of the flexible layer. Claim 3 A pressurizing device according to claim 1 or 2, wherein the control device contacts the interposed pad with the workpiece to hold the workpiece with the interposed pad, and then performs heating and pressurizing of the workpiece by the lower heating mold. Claim 4 delete Claim 5 A pressurizing method for pressurizing and heating a workpiece placed on a support stand, comprising: a heating step of pressurizing the workpiece by clamping the support stand on which the workpiece is placed with an upper die and a lower die for heating heated by a heating means, and heating the workpiece with heat from the lower die for heating; and a cooling step of pressurizing the workpiece by clamping the support stand with an upper die and a lower die for cooling cooled by a cooling means, and cooling the workpiece, wherein an interposed pad is interposed between the upper die and the workpiece, and the interposed pad includes a flexible layer that is flexibly deformed according to the shape of the workpiece, and an insulating layer interposed between the flexible layer and the workpiece to insulate the space between the workpiece and the flexible layer, wherein an intermediate sheet for preventing adhesion is disposed between the insulating layer and the workpiece, and by pressing a side type disposed around the upper die against the support stand, the side type, A pressurization method characterized by forming a sealed space around the workpiece by means of a mold and the mounting base, sucking air within the sealed space by means of a suction device to create a vacuum around the workpiece, and, prior to pressurizing the workpiece, directly contacting a seal member disposed on the bottom surface of the side mold with the mounting base to form the sealed space, and simultaneously driving the suction device to create a vacuum around the sealed space. Claim 6 A workpiece is placed on a support stand; an upper die that presses the workpiece placed on the support stand from the upper side; a lower die that is preheated by a heating means and heats the workpiece while pressing it by clamping the support stand together with the upper die; a side die that is positioned around the upper die and forms a sealed space around the workpiece together with the upper die and the support stand by adhering to the support stand; a suction device that sucks air within the sealed space to create a vacuum around the workpiece; a lower die that is precooled by a cooling means and cools the workpiece while pressing it by clamping the support stand together with the upper die; and a control device that controls the operation of the upper die and the lower die, wherein the control device switches the lower die contributing to the pressurization of the workpiece into a heating lower die or a cooling lower die depending on the progress of the pressurization process of the workpiece, and the control device A pressurizing device characterized by, prior to pressurizing a workpiece, bringing the side mold into contact with the mounting base to form the sealed space, and driving the suction device to bring the sealed space into a vacuum state, and the upper unit including the upper mold and the side mold descending and ascending together with the mounting base while vacuum adsorbing the mounting base.

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