JP2018174307A - Compression bonding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compression bonding device capable of preventing occurrence of deviation between work-pieces, while thermally compression-bonding a pair of work-pieces via an anisotropic conductive members.SOLUTION: A compression bonding device 40 has a compression-bonding part 50 for thermally compression-bonding leads of a first work-piece 1 and a second work-piece 2, via a thermosetting resin-based ACF3. The compression-bonding part 50 has a compression member 51 for compressing the second work-piece 2, a heating part 52 for heating the compression member 51, and a pressure adjustment part 53 for compressing the second work-piece 2 against the compression member 51, heated by the heating part 52, with a first pressure lower than a pressure required for securing conductivity, and fusing the base material with heat, and while hardness capable of bonding is maintained after hardening of the base material is started, pressing the second work-piece 2 with a second pressure required for securing the conductivity.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a crimping apparatus.

  Display devices such as liquid crystal displays and organic EL displays are an array process for forming circuits and signal lines on a glass plate, a cell process for forming a panel as a substrate constituting a display region by bonding a pair of glass plates, It is manufactured through a module process for attaching a driver IC or the like for driving outside the display area of the panel.

  As a method for mounting a driver IC, a method using a flexible film-like electronic component on which a driver IC such as a COF (chip on film) is mounted has been conventionally performed. This is a method of crimping and connecting terminals of electronic components to electrodes formed in the horizontal direction parallel to the display surface from around the display area of the panel (see Patent Document 1).

  Hereinafter, such a substrate and an electronic component or the like are referred to as a workpiece. Also, the conductive parts such as the electrodes and terminals of the work that are to be electrically connected to each other are called leads.

  An anisotropic conductive film (ACF: Anisotropic Conductive Film) that secures conductivity between leads of each workpiece by thermocompression bonding is used for the connection between the workpieces. An anisotropic conductive film is a sheet-like member in which a large number of small conductive particles are contained in a resin as a base material. A thermosetting resin is used as the base resin.

  When an anisotropic conductive film is sandwiched between the leads of a pair of workpieces and pressed while heating, the portions of each lead protrude beyond the surface of the workpiece, so the conductive particles in those portions are crushed and lead They are electrically connected to each other. Other portions are not crushed and the thickness is maintained, so that no electrical conductivity is generated and insulation is ensured. Since the base material of the thermosetting resin is cured by heating, the workpieces are mechanically connected to each other.

Japanese Patent No. 3734548

  As described above, in order to heat-press the pair of workpieces via the anisotropic conductive film and ensure the conductivity between the leads, it is necessary to crush the conductive particles by a necessary amount. For this reason, it is necessary to apply a relatively large load to a workpiece in a crimping device that heat-presses the workpiece. However, when a large load is applied to the workpieces, the workpieces may be misaligned. As a result, the positions of the leads to be connected to each other are also shifted, leading to the generation of defective products.

  In order to cope with this, it is conceivable that the pressure bonding apparatus gradually increases from a small pressure at which a deviation is unlikely to occur to a pressure necessary for ensuring conductivity. However, in this case, it takes time until the final crimping is completed, and the heating time becomes longer, so that the positional displacement between the leads due to the expansion of the thermal expansion of the workpiece is also caused.

  The present invention has been proposed in order to solve the above-described problems, and can prevent a shift between workpieces while thermocompression bonding a pair of workpieces through an anisotropic conductive member in a short time. An object is to provide a crimping apparatus.

  In order to achieve the above-described object, the crimping apparatus of the present invention includes a crimping unit that thermocompression-bonds a part having conductivity of a pair of workpieces through an anisotropic conductive member having a thermosetting resin as a base material. The pressure-bonding portion includes a pressure member that pressurizes at least one of the pair of workpieces, a heating portion that heats the pressure member, and the pressure member heated by the heating portion. Hardness that can be bonded after the base material is melted by applying heat to the workpiece with a first pressure lower than the pressure required for ensuring conductivity by the conductive member, and the base material is cured. Is maintained, and a pressure adjusting unit that pressurizes the workpiece with a second pressure necessary to ensure conductivity.

  The pressure adjusting unit may switch from the first pressure to the second pressure within a predetermined time from the start of pressurization of the work by the pressure member. The predetermined time may be 0.2 seconds to 1 second.

  The first pressure may be a quarter or less of the second pressure.

  The pressure adjusting unit may include a pressurizing source for the second pressure, and a driving mechanism that drives the pressurizing member in a direction in which the pressurizing member contacts and separates from the workpiece together with the pressurizing source.

  The first pressure may be set smaller than a pressure that can crush the base material in a molten state.

  According to the present invention, it is possible to prevent occurrence of displacement between works while heat-pressing a pair of works via an anisotropic conductive member in a short time.

It is a perspective view which shows the workpiece | work crimped | bonded by embodiment. It is a top view which shows the lead | read | reed of the workpiece | work crimped | bonded by embodiment. It is a partial cross section side view showing the basic composition of the crimping device of an embodiment. It is a schematic side view which shows the thermocompression bonding part of embodiment of FIG. It is sectional drawing which shows the crimping | compression-bonding part of the workpiece | work and ACF of embodiment of FIG. It is a block diagram which shows the control apparatus of embodiment of FIG. It is a graph which shows the change with the passage of time of the pressure of pressure member, temperature, height, and the hardness of a substrate. It is a flowchart which shows the procedure of the thermocompression bonding of embodiment.

  Embodiments of the present invention (hereinafter referred to as the present embodiments) will be specifically described with reference to the drawings.

[Crimping target]
With reference to FIG.1 and FIG.2, the 1st workpiece | work 1 and the 2nd workpiece | work 2 which are the crimping | compression-bonding objects by this embodiment, and ACF3 are demonstrated. The first work 1 is a display panel having a display area such as a liquid crystal display or an organic EL display. Depending on the size of such a display panel, a plurality of second workpieces 2 are crimped as shown in FIG. 1 (A) and a single first panel as shown in FIG. 1 (B). 2 work 2 may be crimped. In this embodiment, an example in which a plurality of workpieces 2 are crimped will be described.

  As shown in FIG. 2, leads 11 that are conductive portions are provided on the sides of the first workpiece 1. Each lead 11 is connected to a circuit in the display area via a signal line. A plurality of leads 11 are arranged side by side at a predetermined interval (pitch p). The plurality of leads 11 have, for example, a maximum pitch p (a distance between center lines) of 40 μm or less.

  As shown in FIG. 1A, the second workpiece 2 is an electronic component that is joined to the first workpiece 1 via the ACF 3. As the electronic component, COF (chip on film) is used. The COF is a member in which, for example, a driver IC is mounted on a flexible sheet using a flexible resin and a printed wiring is formed.

  As shown in FIG. 2, a lead 21 which is a conductive part is provided on one side of the second workpiece 2. The lead 21 is a portion for electrically connecting to the lead 11 of the first workpiece 1. Each lead 21 is connected to the driver IC via a signal line. A plurality of leads 21 are arranged side by side at a predetermined interval. The lead 11 of the first work 1 and the lead 21 of the second work 2 have a corresponding relationship to be connected to each other, and need to be crimped so that the corresponding leads 11 and 21 are positioned. . For this reason, the distance between the leads 11 and 22 also coincides. This coincidence may be such that the conductivity between the corresponding leads 11 and 21 can be ensured and the insulation between the adjacent leads 11 and 21 can be ensured.

  ACF 3 is an anisotropic conductive member, and is a film in which conductive particles 32 are dispersed in a base material 31 to form a film (see FIG. 5A). As the base material 31, a thermosetting resin that is cured by heating is used.

  When the ACF 3 is sandwiched between the second workpiece 2 and the first workpiece 1 and pressed while being heated, the conductive particles 32 positioned between the lead 21 and the lead 11 become the leads 11, 21. As a result of being sandwiched between and being crushed, electrical conductivity in the thickness direction between the lead 21 and the lead 11 and insulation in the surface direction are realized (see FIG. 5B). Further, the thermosetting resin of the base material 31 is cured by heating, and the second work 2 is bonded to the first work 1. That is, electrical connection between the lead 11 and the lead 21 and mechanical connection between the first workpiece 1 and the second workpiece 2 can be realized by thermocompression bonding.

(Cause of deviation)
When the second workpiece 2 is thermocompression-bonded to the first workpiece 1 via the ACF 3 as described above, a positional deviation in the surface direction may occur between the first workpiece 1 and the second workpiece 2. . As a result of intensive studies, the inventor has discovered that the cause of this misalignment is due to the property that the thermosetting resin is melted once before being cured by heating and the hardness is significantly reduced, and then curing is started. . That is, when a high pressure is applied at the stage where the base material 31 is melted and the hardness until the crosslinking reaction is started, the base material 31 tends to flow and is not stable. As a result, slipping was likely to occur as if the lubricant was sandwiched between the two workpieces, and as a result, it was found that a deviation in the surface direction occurred between the workpieces 1 and 2. Therefore, it has been found that this problem can be solved by applying a high pressure after at least the thermosetting resin is melted and then starting to cure, that is, after the crosslinking reaction has started.

  However, the thermosetting resin cannot be bonded when the curing proceeds and the hardness increases. For this reason, a high pressure must be applied after curing has started and while viscosity is produced by melting. After the thermosetting resin is melted by heating and curing is started, the time during which the hardness capable of bonding between the workpieces is maintained is very short. Accordingly, unless the thermosetting resin is melted by pressurization with a low pressure and then switched to a high pressure within a very short time, it is impossible to prevent deviation and ensure adhesion.

  In the present embodiment, as will be described later, the pressurizing member 51 heated by the heating unit 52 pressurizes the second work 2 with a first pressure lower than the pressure necessary for ensuring conductivity, Under the condition, the base material 31 is melted by heat. The first pressure is applied to the pressurizing member 51 while securing the conductivity after the melted base material 31 starts to be cured by heat, and the second pressure necessary to ensure conductivity. The pressure of the second workpiece 2 is increased by the second pressure. This succeeded in preventing slippage and ensuring adhesion. Details of this embodiment will be described below.

[Constitution]
The configuration of the crimping apparatus 40 of this embodiment will be described with reference to FIGS. 3 and 4. In FIG. 3, the direction between the front and the back is the Y direction, the direction perpendicular to the Y direction is the X direction, the vertical direction is the Z direction, and the horizontal rotation direction is the θ direction. The pressure bonding device 40 includes a pressure bonding portion 50, a pressure receiving portion 60, a support portion 70, and a control device 80.

  The crimping portion 50 is a component that heat-presses the lead 11 and the lead 21 of the first workpiece 1 and the second workpiece 2 via the ACF 3. The crimping part 50 includes a pressing member 51, a heating part 52, and a pressure adjusting part 53. Note that the second workpiece 2 is described as being supplied to the crimping device 40 in a state of being temporarily crimped to the first workpiece via the ACF 3 by the temporary crimping device disposed in the previous process of the crimping device 40. To do.

  The pressure member 51 is a member that pressurizes the second workpiece 2. The pressurizing member 51 has a substantially rectangular parallelepiped shape that is long in the Y direction, and is a length that allows a plurality of second workpieces 2 that are temporarily press-bonded to the first workpiece 1 to be heat-bonded together (so-called main pressing). have. On the surface of the pressure member 51 that faces the second workpiece 2, there is a pressure portion 51 a that protrudes in a band shape. The pressurizing unit 51 a has a flat pressurizing surface facing the second workpiece 2 in parallel.

  In addition, although illustration is abbreviate | omitted in FIG. 3, as shown to FIG. 4 (A), the cushion sheet B exists between the pressurization member 51 and the 2nd workpiece | work 2. As shown in FIG. The cushion sheet B is a cushioning sheet, is wound around a supply reel (not shown), is sent out by rotation, is wound around a collection reel, and is collected.

  The heating unit 52 is a member that heats the pressure member 51. The heating unit 52 is built in the pressure member 51. The heating unit 52 uses, for example, a heater that generates heat when a voltage is applied. A plurality of heaters are embedded at equal intervals in the pressure member 51 at the back of the pressure unit 51a.

  The pressure adjusting unit 53 pressurizes the second workpiece 2 to the pressurizing member 51 heated by the heating unit 52 with a first pressure lower than the pressure necessary for ensuring conductivity by the ACF3 and heats the ACF3. The base material 31 is melted, and the second workpiece is pressurized with the second pressure necessary to ensure conductivity while the hardenable adhesion is maintained after the base material 31 is cured. .

  The “pressure necessary for ensuring conductivity” is a pressure at which conductivity is obtained between the lead 11 of the first workpiece 1 and the lead 21 of the second workpiece 2 due to the collapse of the conductive particles 32. It is conceivable that the first pressure lower than this is, for example, not more than a quarter of the second pressure. Furthermore, the first pressure is preferably a pressure that can maintain the thickness of the base material 31 without being crushed even when the base material 31 is melted and the hardness is most reduced. Such first pressure and second pressure may be obtained by experiments or the like. The “start of curing of the base material 31” is after the time when the hardness is reduced most. “Hardness that can be adhered is maintained” means that the material has a viscosity that allows adhesion and is within the range of the curing rate that allows adhesion.

  The pressure adjustment unit 53 includes a pressurization source 55 and a drive mechanism 56. The pressure source 55 is a device that applies pressure to the pressure member 51. In the present embodiment, the pressurization source 55 serves as a generation source of the first pressure and the second pressure. For example, an air cylinder that generates pressure by the action of compressed air is used as the pressure source 55. The pressurizing source 55 has an operating rod 55a that applies pressure by linear motion. The operating rod 55a is advanced and retracted in the Z direction by the pressure source 55. Further, the pressure source 55 is provided with a pressure sensor 55b for detecting the pressure applied to the second workpiece 2.

  Further, the operating rod 55a is connected to the pressurizing member 51 through the elevating block 55c. The elevating block 55c is a rectangular parallelepiped member, and elevates and lowers the pressure member 51 as the operating rod 55a advances and retreats.

  The drive mechanism 56 is a mechanism that drives the pressure member 51 together with the pressure source 55 in a direction in which the pressure member 51 contacts and separates from the second workpiece 2. The drive mechanism 56 includes a frame 561, a motor 562, a ball screw 563, a nut member 564, a base plate 565, and guide rails 566 and 567.

  The frame body 561 is a box-like member fixed to a housing or the like of the crimping device 40 (not shown). The motor 562 is a drive source fixed to the upper part of the frame body 561. The ball screw 563 is disposed inside the frame body 561 along the Z direction and is supported so as to rotate about an axis. The nut member 564 is a member that moves up and down along the ball screw 563 by the rotation of the ball screw 563. The nut member 564 protrudes from a window hole formed on the side surface of the frame body 561.

  The base plate 565 is a member that extends in the Z direction and supports the lifting block 55 c together with the pressure source 55. The base plate 565 is attached to a nut member 564 protruding from the frame body 561. The guide rail 566 is a rail provided on the base plate 565 along the Z direction, and supports the elevating block 55c so as to be slidable. The guide rail 567 is a rail provided on the frame body 561 along the Z direction, and supports the base plate 565 so as to be slidable.

  The pressure receiving unit 60 is a member that sandwiches the second workpiece 2 and the first workpiece 1 with the pressurizing unit 51 a of the pressurizing member 51. The pressure receiving portion 60 is a substantially rectangular parallelepiped member that can be moved up and down by a lifting mechanism (not shown), and has a length equivalent to that of the pressure member 51. The pressure receiving unit 60 includes a backup unit 61 and a heating unit 62. The backup unit 61 is provided on the surface facing the pressurizing unit 51a, and extends in the Y direction, that is, the side direction of the first workpiece 1, and protrudes in a band shape. The backup unit 61 has a receiving surface with a flat surface facing the pressing surface of the pressing unit 51a.

  The pressure receiving unit 60 is set so that the receiving surface of the backup unit 61 is flush with the lower surface of the first work 1 supported by the stage 71 described later when the pressure receiving unit 60 comes to the raised position. The pressure receiving unit 60 may be provided immovably so that the receiving surface of the backup unit 61 has the same height as the lower surface of the first workpiece 1.

  The heating unit 62 is a member that is built in the pressure receiving unit 60 and heats the backup unit 61. The heating unit 62 uses, for example, a heater that generates heat when a voltage is applied. A plurality of heating units 62 are embedded at equal intervals in the pressure receiving unit 60 on the back of the backup unit 61.

  The support unit 70 is a device that supports the first workpiece 1. The support unit 70 includes a stage 71 and a moving device 72. The stage 71 is a flat table that supports the first workpiece 1 in the horizontal direction. Although not shown, the stage 71 is formed with a plurality of holes connected to a vacuum source so that the first workpiece 1 can be sucked and held. The moving device 72 is a device that supports the stage 71 movably in the X direction, the Y direction, and the θ direction.

  The support part 70 receives the first work 1 in which the second work 2 is temporarily pressure-bonded via the ACF 3 from a pre-process such as a temporary pressure bonding apparatus, and the second work 2 is received by the pressurizing part 51a. The first workpiece 1 is moved so as to come to the crimping position where the workpiece 1 is crimped. Moreover, the support part 70 delivers the 1st workpiece | work 1 in which the crimping | compression-bonding operation was completed to post processes, such as a board | substrate storage apparatus.

  The control device 80 is a device that controls the crimping device 40. The control device 80 is configured by, for example, a dedicated electronic circuit or a computer that operates with a predetermined program. That is, the operation of the crimping device 40 is controlled by operating the motor 562, the pressure source 55, the heating unit 52, the heating unit 62, the moving device 72, and the like. The control contents are programmed with respect to the operation timing of the motor 562, the rotation speed, the operation timing and pressure of the pressure source 55, the heating temperature of the heating unit 52 and the heating unit 62, the operation of the moving device 72, etc. The program is executed by a processing apparatus such as the above, and can cope with various specifications of the first workpiece 1, the second workpiece 2, and the ACF 3 to be crimped.

  As shown in FIG. 6, the control device 80 includes a detection unit 81, a pressure control unit 82, a first temperature control unit 83, a second temperature control unit 84, a mechanism control unit 85, a storage unit 86, a setting unit 87, An input / output control unit 88 is included. The detection part 81 detects the press with respect to the 2nd workpiece | work 2 of the pressurization member 51 based on the signal from the pressure sensor 55b.

  The pressure control unit 82 controls the crimping operation on the second workpiece 2 and the first workpiece 1 by outputting an instruction signal to the pressure adjustment unit 53 according to the signal from the pressure sensor 55b and the set timing and pressure. To do. More specifically, the drive mechanism 56 instructs the raising / lowering timing, the raising / lowering speed of the pressurizing source 55, the pressurizing timing of the pressurizing source 55, and the applied pressure so that the pressure adjusting unit 53 operates as described above.

  The first temperature control unit 83 outputs a signal for instructing the temperature of the heating unit 52 so as to be the curing temperature of the base material 31 of ACF3. This curing temperature is a temperature necessary for thermally curing the base material 31 and is, for example, 200 ° C. The second temperature control unit 84 outputs a signal instructing the temperature of the heating unit 62 so as to be a temperature that assists the heating unit 52. This temperature is, for example, 80 ° C.

  The mechanism control unit 85 operates the pressurization source 55, the motor 562, the heating unit 52, the heating unit 62, and the moving device 72 in accordance with instructions from the pressure control unit 82. When the pressurization source 55 is an air cylinder, the mechanism control unit 85 controls the pressure of compressed air supplied to the air cylinder. The storage unit 86 stores information necessary for the control of the present embodiment. The information stored in the storage unit 86 includes the operation timing of the motor 562, the operation timing and pressure of the pressurizing source 55, the heating temperature by the heating units 52 and 62, the pressure release timing, and the like. The various timings described above can be controlled by, for example, the time from the start of pressing by the pressure member 51 detected by the pressure sensor 55b.

  The setting unit 87 is a processing unit that sets information input from the outside in the storage unit 86. The input / output control unit 88 is an interface for controlling signal conversion and input / output with each unit to be controlled.

  Further, an input device 91 and an output device 92 are connected to the control device 80. The input device 91 is input means such as a switch, a touch panel, a keyboard, and a mouse for an operator to operate the crimping device 40 via the control device 80. The operator can input desired operation timing, pressure, temperature, and the like by using the input device 91.

  The output device 92 is output means such as a display, a lamp, and a meter that makes information for confirming the state of the device visible to the operator. For example, the output device 92 can display an information input screen from the input device 91. In this case, as shown in FIG. 7 described later, information may be input by displaying a graph and inputting a numerical value or selecting the inside of the graph.

[Operation]
Next, an operation example of this embodiment will be described with reference to FIGS. 7 and 8 in addition to FIGS. FIG. 7 is a graph showing the amount of operation of each unit over time. The horizontal axis is common in time (sec). The vertical axis indicates the relative displacement from the starting point t0 with respect to the hardness and heating temperature of the base material 31 of ACF3, the pressure of the pressure source 55, and the position of the base plate 565 in the height direction. The hardness becomes lower as it goes down and becomes a liquefied state by melting, and becomes higher as it goes up and the tackiness is lost. The height of the base plate 565 is shown separately in the lower graph. The base plate 565 continues to descend until the height h reaches the height h at t4 even after the pressure surface of the pressure unit 51a contacts the second workpiece 2 at t1. FIG. 8 is a flowchart showing the procedure of the thermocompression bonding operation of the present embodiment.

  First, the first work 1 to which the second work 2 is temporarily press-bonded via the ACF 3 is placed on the stage 71 of the support unit 70, and the first work 1 and the second work 2 are moved by the moving device 72. Comes to the crimping position. Then, the pressure receiving unit 60 rises and the receiving surface of the backup unit 61 comes to a position in contact with the lower surface of the first work 1. The pressing member 51 and the backup unit 61 are heated by the heating units 52 and 62, respectively.

  In this state, the pressure member 51 starts to descend from the time t0 in FIG. 7 by the operation of the drive mechanism 56 (step 101). At t1, the pressing surface of the pressing unit 51a contacts the second workpiece 2 via the cushion sheet B, so that the backup unit 61 that supports the lower surface of the first workpiece 1 as shown in FIG. Thus, the lowering of the pressure member 51 is stopped. The pressing of the pressing member 51 against the second workpiece 2 is detected by the detection unit 81 based on a signal from the pressure sensor 55b (YES in step 102).

  At this time, the pressurizing force of the pressurizing source 55 that is an air cylinder is constant, but the pressurizing member 51 is connected to the operating rod 55 a of the pressurizing source 55. For this reason, when the drive mechanism 56 continues the lowering operation, the operating rod 55a is pushed into the cylinder. Thereby, as shown in FIG. 7, the first pressure is applied to the second workpiece 2. This pressure is a first pressure lower than the pressure required for ensuring conductivity by the ACF 3. Here, it is conceivable that the first pressure is smaller than the pressure applied by the weight of the pressure member 51 and the lifting block 55c. In such a case, a force in the pulling direction may be applied to the lifting block 55c by the difference between the pressure due to its own weight and the first pressure by the pressurizing source 55. That is, the pressure source 55 functions as a pressure generation source including applying a force in the pulling direction with a force smaller than the total weight of the pressure member 51 and the lifting block 55c.

  On the other hand, since the pressure surface of the pressure unit 51a approaches the second workpiece 2 from t0, the base 31 of the ACF 3 is heated by the heating unit 62 of the backup unit 61 and the radiant heat from the pressure unit 51a. Then, the temperature starts to rise, and when the pressure surface comes into contact with the second workpiece 2 at t1, the temperature rises rapidly. In this process, the base material 31 starts to melt and the hardness decreases, and after reaching a state where the hardness is lowest at t2, for example, 0.2 seconds from t1, the curing starts. However, the time t2 until the hardness becomes the lowest varies depending on the type of the base material 31. In this manner, since the pressure applied to the second workpiece 2 is the low first pressure until the base material 31 starts to be cured, the melted base material 31 can be prevented from being crushed. The deviation of the lead 21 and the lead 11 due to the sliding of the second workpiece 2 that is likely to occur when the base material 31 is crushed with respect to the first workpiece 1 is prevented.

  After curing starts at t2, the pressure of the pressure source 55 is increased at t3. That is, the pressure of the pressurizing source 55 is increased at a timing when a predetermined time has elapsed from the start of pressing (t1) (YES in step 103) (step 104). The predetermined time is, for example, 0.5 seconds. As a result, at t4, the pressure rises to the second pressure necessary for securing the conductivity by the ACF3. In this way, at the time point t4 when the second pressure is reached, after the hardening of the base material 31 is started (t2), the second workpiece 2 and the first workpiece 1 have a viscosity that allows the first workpiece 1 to be bonded t5. Until. That is, “the hardness that can be bonded is maintained” means that it has a viscosity that allows bonding. In FIG. 7, it is a period between t2 and t5, for example, a period of 0.2 to 1 second from the start of pressing (t1).

  At t4, the drive mechanism 56 stops the lowering operation. As a result, as shown in FIG. 5B, the conductive particles 32 are crushed, the conductivity between the lead 21 and the lead 11 is ensured, and the electrical connection is established. Thereafter, the curing of the base material 31 further proceeds and the thermocompression bonding is completed, that is, the base material 31 is cured until reaching t6 which is the time when the crimping time elapses, and the second work 2 and the first work 1 Are joined and a mechanical connection is established.

  At the time t1, that is, when a predetermined pressure bonding time has elapsed from the start of pressing (YES in Step 105), the driving mechanism 56 raises the pressure source 55 to raise the pressure member 51, and the second work 2 is moved. Release from pressurization (step 106). The crimping time is, for example, 5 seconds.

[Function and effect]
(1) According to the embodiment as described above, pressure bonding is performed by thermocompression bonding the lead 11 of the first workpiece 1 and the lead 21 of the second workpiece 2 through the ACF 3 having the thermosetting resin as the base material 31. The pressure bonding unit 50 includes a pressing member 51 that pressurizes the second workpiece 2 against the first workpiece 1, a heating unit 52 that heats the pressing member 51, and heating by the heating unit 52. The pressurizing member 51 is pressed against the second workpiece 2 by a first pressure lower than the pressure required to ensure conductivity by the ACF 3 and the base material 31 is melted by heat to cure the base material 31. And a pressure adjusting unit 53 that pressurizes the second workpiece 2 with a second pressure necessary to ensure conductivity while maintaining the hardness capable of being bonded after the start of the process.

  For this reason, while the thermosetting resin is melted, the position where misalignment is likely to occur between the first and second workpieces 1 and 2 is prevented from being misaligned by pressurizing with a low pressure during the period. After the curable resin starts to harden and it is difficult for the position shift to occur, it is possible to apply pressure at which the conductive particles are crushed to ensure conductivity. In addition, since a high pressure is applied while maintaining a bondable hardness, there is no problem with mechanical connection. Accordingly, the pressure is not gradually increased to a pressure at which electrical conductivity can be ensured, but is switched from the first pressure to the second pressure in a very short time. 21 can also be prevented from being displaced.

(2) The pressure adjusting unit 53 switches from the first pressure to the second pressure within a predetermined time from the start of pressurization of the second workpiece 2 by the pressurizing member 51. The timing for switching can be obtained by experiments or the like. For example, even if the second pressure is applied during the time when the base material 31 starts to be cured after the heated pressure member 51 starts to press and the viscosity necessary for bonding is maintained. What is necessary is just to obtain | require the timing which a shift | offset | difference does not arise between the 1st, 2nd workpiece | work 1,2. The pressure adjustment unit 53 performs control to switch the pressure in accordance with this, whereby the deviation can be prevented.

(3) According to the inventor's experiment, the period during which the base material 31 starts to be cured after the pressing by the pressing member 51 and the viscosity necessary for adhesion is maintained is 0.2 seconds to 1 second. It is. In this case, it is preferable to set the time (switching time) from when the pressing is started until switching to the second pressure to 0.2 second to 1 second. More preferably, the second pressure may be applied within a switching time of 0.5 seconds to 1 second. By doing in this way, position shift can be prevented.

(4) The first pressure is ¼ or less of the second pressure. For this reason, before the base material 31 is melted and curing is started, it is possible to reliably prevent the positional deviation as a pressure much lower than the pressure for ensuring conductivity. More specifically, the first pressure is a pressure that does not crush the molten base material 31, in other words, a pressure that can maintain the shape of the molten base material 31. . For this reason, until the second pressure is applied, the molten base material 31 does not need to be crushed, so the first and second workpieces 1 that are likely to occur when the molten base material 31 is crushed, Misalignment between the two can be prevented. As a result, the crimping accuracy of the first and second workpieces 1 and 2 can be improved.

(5) The pressure adjusting unit 53 includes a pressure source 55 for the second pressure, and a drive mechanism 56 that drives the pressure member 51 in the direction of contacting and separating from the second workpiece 2 together with the pressure source 55. . For this reason, after the pressing member 51 is pressed against the second workpiece 2 by the driving mechanism 56 to apply the first pressure, the pressing member 51 is pressed by the pressing source 55 at the timing as described above. A pressure of 2 can be applied. Then, since the pressurization source 55 only needs to switch the pressure from a constant state to an increase at a preset timing, the first pressurization source 55 has a first pressure rather than changing the slope of the pressure increase on the way. The switching timing from the first pressure to the second pressure can be accurately controlled.

(6) The conductive portions of the pair of workpieces are the plurality of leads 11 and 21, and the pitch p of the plurality of leads 11 and 21 is 40 μm or less at the maximum. Thus, even if the first workpiece 1 and the second workpiece 2 are high-definition parts, it is possible to reliably ensure the conductivity between the corresponding leads and the insulation between the non-corresponding leads.

[Modification]
(1) The pressure adjustment unit 53 is not limited to an aspect in which the pressure is adjusted by a combination of the pressurization source 55 and the drive mechanism 56. A mode in which the pressure is adjusted only by the pressurizing source 55 may be used. As the pressurizing source 55, a hydraulic cylinder, a ball screw mechanism, or the like may be used in addition to the pneumatic cylinder.

(2) The 1st workpiece | work 1 is good also as a member provided with the part which has electroconductivity other than a display panel. The portion having conductivity is not limited to the plane of the first workpiece 1, and may be a side surface of the first workpiece 1. For example, the first workpiece 1 may be a rectangular substrate, and the lead is exposed on the side surface. In this case, the pressure receiving portion 60 that sandwiches the second workpiece 2 and the first workpiece 1 on the side facing the crimping portion 50 may not be provided.

  The material of the board | substrate of the 2nd workpiece | work 2 is not limited to resin-made flexible things. A glass substrate may be used for the second workpiece 2. The first workpiece 1 may be a resin-made flexible substrate instead of a glass-made substrate.

(3) In the above aspect, the plurality of second workpieces 2 temporarily bonded to one side of the first workpiece 1 are collectively bonded together by using one long pressing member 51. It was an aspect. However, the method of this crimping | compression-bonding is not limited to this, It is set as the structure which arranged the pressurization surface of the pressurization member 51 of the length corresponding to the 2nd workpiece | work 2 side by side corresponding to each one. You can also. The structure for applying pressure to the pressure member 51 such as the pressure source 55 may also be provided individually for each of the plurality of pressure members 51.

  Moreover, although said aspect was an aspect which carries out the main pressure bonding of the several 2nd workpiece | work 2 to one edge | side of the 1st workpiece | work 1, as shown to FIG. The present invention can also be applied to a mode in which a single second workpiece 2 is permanently bonded to one side. Furthermore, the present invention can also be applied to a mode in which one or a plurality of second workpieces are permanently bonded to a plurality of sides of the first workpiece 1.

  Moreover, even if it is the structure which makes the 1st workpiece | work 1 the pressure side as a receiving side by which the 2nd workpiece | work 2 is supported, it pressurizes from both the 1st workpiece | work 1 and the 2nd workpiece | work 2. It may be a configuration.

(4) In the above aspect, the interval between the leads 11 of the first workpiece 1 and the interval between the leads 21 of the second workpiece 2 coincide with each other before the interval between the workpieces 1 and 2 is thermocompression-bonded. It includes not only those that match in the state but also those that are formed with different intervals between the leads 11 and 21 of both the workpieces 1 and 2 so as to allow for thermal expansion so that the intervals match after thermocompression bonding.

[Other Embodiments]
As mentioned above, although embodiment of this invention and the modification of each part were demonstrated, this embodiment and the modification of each part are shown as an example, and are not intending limiting the range of invention. These novel embodiments described above can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention and included in the invention described in the claims.

1 First work 11 Lead 2 Second work 21 Lead 3 ACF
31 Substrate 32 Conductive Particle 40 Crimping Device 50 Crimping Unit 51 Pressing Member 52 Heating Unit 53 Pressure Adjusting Unit 55 Pressurizing Source 55a Actuating Rod 55b Pressure Sensor 55c Lifting Block 56 Drive Mechanism 561 Frame 562 Motor 563 Ball Screw 564 Nut Member 565 Base plates 566, 567 Guide rail 60 Pressure receiving portion 61 Backup portion 62 Heating portion 70 Supporting portion 71 Stage 72 Moving device B Cushion sheet 80 Control device 81 Detection portion 82 Pressure control portion 83 First temperature control portion 84 Second temperature Control unit 85 Mechanism control unit 86 Storage unit 87 Setting unit 88 Input / output control unit

Claims (6)

Through a anisotropic conductive member based on a thermosetting resin, it has a pressure-bonding part that heat-presses the conductive part of a pair of workpieces,
The crimping part is
A pressure member that pressurizes at least one of the pair of workpieces;
A heating unit for heating the pressure member;
The pressure member heated by the heating unit is pressurized with the work by a first pressure lower than the pressure necessary for ensuring conductivity by the anisotropic conductive member, and the base material is melted by heat. And a pressure adjusting unit that pressurizes the workpiece with a second pressure necessary to ensure conductivity while the hardness capable of being adhered after the curing of the base material is maintained,
A crimping apparatus comprising:   The pressure bonding apparatus according to claim 1, wherein the pressure adjusting unit switches from the first pressure to the second pressure within a predetermined time from the start of pressurization of the workpiece by the pressure member.   The crimping apparatus according to claim 2, wherein the predetermined time is 0.2 second to 1 second.   The pressure bonding apparatus according to any one of claims 1 to 3, wherein the first pressure is ¼ or less of the second pressure. The pressure adjusting unit is
A pressurizing source of the second pressure;
A driving mechanism that drives the pressurizing member in a direction of contacting and separating the pressurizing member together with the pressurizing source;
The crimping apparatus according to claim 1, comprising:   The crimping apparatus according to claim 1, wherein the first pressure is set to be smaller than a pressure that can crush the base material in a molten state.

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