Wire bonding device and bonding method for bonding wire

Abstract

A wire bonding device according to the present invention comprises: a capillary that extends in a prescribed axial direction and is for bonding a bonding wire to an overhang portion; a bonding tool that holds the capillary and can move the capillary in a Z-axis direction along a prescribed axis and in a drive plane intersecting the Z-axis direction; and a controller that controls movement of the capillary by the bonding tool. The controller, by providing a control signal to the bonding tool, simultaneously executes a bonding operation for moving the capillary along the Z-axis in a state in which the capillary has received a reaction force from the overhang portion, and an adjustment operation that moves the capillary along the drive plane.

Description

Wire bonding apparatus and method for bonding bonding wires

[0001] The present disclosure relates to a wire bonding apparatus and a method for bonding bonding wires.

[0002] A wire bonding apparatus bonds a bonding wire to an electrode of a semiconductor chip. The bonding wire is pressed against an electrode or the like of a semiconductor chip from a component called a capillary, and receives heat, ultrasonic waves, or the like from the capillary as necessary. As a result, the bonding wire is bonded to the electrode or the like of the semiconductor chip. Such a bonding operation is referred to as bonding. Patent Document 1 discloses a technology related to a wire bonding apparatus.

[0003] Japanese Unexamined Patent Publication No. 10-284532

[0004] An object to which a bonding wire is bonded may be deformed by a force received from a capillary. As a result of a wire bonding operation involving deformation of the bonding object, the shape of the bonding wire bonded to the bonding object may not become a desired shape.

[0005] The present disclosure describes a wire bonding apparatus and a method for bonding a bonding wire, which can make the bonded bonding wire have a desired shape in wire bonding involving deformation of a bonding object.

[0006] A wire bonding apparatus according to one aspect of the present disclosure includes: a capillary extending in a direction of a predetermined axis for bonding a bonding wire to a bonding object; a bonding tool that holds the capillary and is capable of moving the capillary in a first direction along the predetermined axis and a second direction intersecting the first direction; and a controller that controls movement of the capillary by the bonding tool. The controller applies a control signal to the bonding tool to execute in parallel a bonding operation of moving the capillary along the first direction and an adjustment operation of moving the capillary along the second direction, in a state where the capillary receives a reaction force from the bonding object.

[0007] The controller of the wire bonding apparatus moves the capillary along a first direction while the capillary receives a reaction force from the object to be bonded. This action allows the bonding wire to be pressed against the object to be bonded with a desired load. Furthermore, the controller moves the capillary along a second direction in parallel with the bonding operation of moving the capillary along the first direction. This movement along the second direction allows the position of the capillary to follow the deformation of the object to be bonded. As a result, in wire bonding involving deformation of the object to be bonded, the bonded bonding wire can be made into a desired shape.

[0008] In the wire bonding apparatus described above, the bonding operation may include an operation to move the capillary toward the object to be bonded, and an operation to move the capillary toward the object to be bonded. When the operation is to move the capillary toward the object to be bonded, the controller may simultaneously perform an adjustment operation to move the capillary toward the second direction. This operation allows the capillary to be moved in a way that prevents unintended deformation from occurring in the bonding wire bonded to the object to be bonded.

[0009] In the wire bonding apparatus described above, the bonding operation may include an operation to move the capillary toward the object to be bonded and an operation to move the capillary toward the object to be bonded. When the operation is to move the capillary toward the object to be bonded, the controller may simultaneously perform an adjustment operation to move the capillary toward the second direction. This operation makes it possible to maintain the position in which the capillary presses the bonding wire against the object to be bonded, even if the object to be bonded is deformed.

[0010] In the wire bonding apparatus described above, a pre-touch position where the bonding wire is in contact with the object to be bonded and a bond completion position where the bonding of the bonding wire to the object to be bonded is completed may be defined. The distance along the first direction from the pre-touch position to the bond completion position may be greater than the distance along the second direction from the pre-touch position to the bond completion position. In this embodiment as well, in wire bonding involving deformation of the object to be bonded, the bonded bonding wire can be made into a desired shape.

[0011] In the wire bonding apparatus described above, a pre-touch position where the bonding wire is in contact with the object to be bonded and a bond completion position where the bonding of the bonding wire to the object to be bonded is completed may be defined. The trajectory that the tip of the capillary travels through as it moves from the pre-touch position to the bond completion position may include a straight section. This trajectory simplifies the control of the movement of the capillary by the bonding tool.

[0012] In the wire bonding apparatus described above, a pre-touch position where the bonding wire is in contact with the object to be bonded and a bond completion position where the bonding of the bonding wire to the object to be bonded is completed may be defined. The trajectory that the tip of the capillary travels through as it moves from the pre-touch position to the bond completion position may include a curved portion. This trajectory allows the capillary to accurately follow the deformation of the object to be bonded.

[0013] In the wire bonding apparatus described above, a pre-touch position where the bonding wire is in contact with the object to be bonded and a bond completion position where the bonding of the bonding wire to the object to be bonded is completed may be defined. The trajectory that the tip of the capillary travels from the pre-touch position to the bond completion position may be the same as the trajectory that the tip of the capillary travels from the bond completion position to the pre-touch position. This operation simplifies the control of the movement of the capillary by the bonding tool.

[0014] In the wire bonding apparatus described above, a pre-touch position where the bonding wire is in contact with the object to be bonded and a bond completion position where the bonding of the bonding wire to the object to be bonded is completed may be defined. The trajectory that the tip of the capillary travels from the pre-touch position to the bond completion position may be different from the trajectory that the tip of the capillary travels from the bond completion position to the pre-touch position. This operation allows for greater flexibility in setting the trajectory.

[0015] Another embodiment of the present disclosure is a method for joining bonding wires, which involves joining a bonding wire to an object to be joined using a capillary extending in the direction of a predetermined axis, and comprising the steps of: ensuring that the capillary is receiving a reaction force from the object to be joined; performing a joining operation in parallel, which involves moving the capillary along a first direction along the predetermined axis; and performing an adjustment operation in parallel, which involves moving the capillary along a second direction intersecting the first direction. With this method, similar to the wire bonding apparatus described above, the joined bonding wires can be made into a desired shape in wire bonding that involves deformation of the object to be joined.

[0016] The wire bonding apparatus and method for joining bonding wires of this disclosure can make the joined bonding wires into a desired shape in wire bonding that involves deformation of the objects to be joined.

[0017] Figure 1 is a schematic diagram showing the configuration of a wire bonding apparatus according to an embodiment. Figure 2 is an enlarged view illustrating the overhang portion before deformation and the overhang portion after deformation. Figures 3(a) and 3(b) illustrate the effect on the bonding wire due to the deformation of the overhang portion. Figures 4(a) and 4(b) illustrate the bonding operation by the wire bonding apparatus according to the embodiment. Figure 5 is a flowchart of the method for joining bonding wires according to an embodiment. Figures 6(a), 6(b), 6(c), and 6(d) illustrate the main steps of the method for joining bonding wires. Figures 7(a), 7(b), and 7(c) are diagrams that, following Figure 6, illustrate the main steps of the method for joining bonding wires. Figure 8 is an example of an overhang portion with displacement in the X-axis and Y-axis directions. Figure 9(a) is a diagram illustrating the operation of the wire bonding apparatus of Modification 1. Figure 9(b) is a diagram illustrating the operation of the wire bonding apparatus of Modification 2.

[0018] The wire bonding apparatus and method for joining bonding wires described herein will be explained in detail below with reference to the attached drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant explanations are omitted.

[0019] The wire bonding apparatus 1 shown in Figure 1 presses the capillary 2 toward the semiconductor device 9 while the bonding wire 8 is sandwiched between the capillary 2 and the electrode of the semiconductor device 9. As a result, the bonding wire 8 is bonded to the electrode. In addition to bonding load, the wire bonding apparatus 1 may also apply ultrasonic waves or heat to the bonding wire 8.

[0020] The semiconductor device 9 includes a substrate 91, a semiconductor device body 92, and an overhang portion 93. Several substrate electrodes 911 are provided on the substrate 91. Several overhang electrodes 931 are also provided on the overhang portion 93. The first end of the bonding wire 8 is joined to the overhang electrode 931. The second end of the bonding wire 8 is joined to the substrate electrode 911.

[0021] The wire bonding apparatus 1 includes a capillary 2, a bonding tool 3, a Z-axis drive unit 4, and an XY-axis drive unit 5.

[0022] The capillary 2 presses the bonding wire 8 against the object to be bonded. The capillary 2 may also apply ultrasonic waves to the bonding wire 8. The capillary 2 has a cylindrical portion and a conical portion, and is provided with a through hole extending from one end face to the other. The bonding wire 8 is fed out through this through hole.

[0023] The bonding tool 3 detachably holds the cylindrical portion of the capillary 2 at its tip. The bonding tool 3 is connected to the Z-axis drive unit 4 at its base. The bonding tool 3 moves the held capillary 2 in the X-axis, Y-axis, and Z-axis directions, respectively.

[0024] The Z-axis drive unit 4 is attached to the XY-axis drive unit 5 and can move in the X-axis and Y-axis directions. The virtual plane defined by these X and Y axes is defined as the drive plane DP. As mentioned above, the base end of the bonding tool 3 is connected to the Z-axis drive unit 4. The Z-axis drive unit 4 moves the bonding tool 3 in the Z-axis direction. The XY-axis drive unit 5 is attached to the base 7. In other words, the XY-axis drive unit 5 does not move like the bonding tool 3 or the Z-axis drive unit 4. The XY-axis drive unit 5 moves the Z-axis drive unit 4 in the X-axis and Y-axis directions.

[0025] The wire bonding apparatus 1 includes a load sensor 31, a Z-axis position sensor 41, and an XY-axis position sensor 51.

[0026] The load sensor 31 detects or measures the reaction force that the capillary 2 receives from the bonding object when the capillary 2 is pressed against the bonding object. For example, the load sensor 31 is used to detect when the capillary 2 or bonding wire 8 is in contact with the bonding object. The load sensor 31 also measures the bonding load that the capillary 2 applies to the bonding wire 8 when it presses against the bonding object. The load sensor 31 passes the detected or measured data D31 to the controller 6, which will be described later.

[0027] The Z-axis position sensor 41 measures the position of the capillary 2 in the Z-axis direction. The XY-axis position sensor 51 measures the position of the capillary 2 in the X-axis direction and the Y-axis direction. Similar to the load sensor 31, the Z-axis position sensor 41 and the XY-axis position sensor 51 pass the measured data D41 and D51 to the controller 6, which will be described later.

[0028] <Controller> The wire bonding apparatus 1 has a controller 6. The controller 6 controls all operations related to the bonding operation. For example, the controller 6 receives data D31, D41, and D51 from the load sensor 31, the Z-axis position sensor 41, and the XY-axis position sensor 51. The controller 6 then controls the Z-axis drive unit 4 and the XY-axis drive unit 5, etc., based on the received data D31, D41, and D51 and the bonded conditions DN it holds.

[0029] The controller 6 is a computer having at least memory 6M and a processor 6P. The memory 6M of the controller 6 holds various data required for the bonding operation. For example, the memory 6M holds the bonding program P. The bonding operation is performed when the processor 6P executes the bonding program P. The memory 6M also includes forward trajectory data DT1, return trajectory data DT2, and bonding conditions DN that specify the movement trajectory of the capillary 2 when performing the bonding operation.

[0030] When the bonding program P is executed by the processor 6P, several functional components shown in Figure 1 are realized. The controller 6 includes, as functional components, a load processing unit 61, a trajectory processing unit 62, a Z-axis position control unit 63, and an XY-axis position control unit 64.

[0031] The load processing unit 61 receives load data D31 from the load sensor 31. For example, the load processing unit 61 may determine that the capillary 2 has come into contact with the object to be joined when the load data D31 changes from zero to a predetermined value. Alternatively, the load processing unit 61 may determine that the capillary 2 has reached the joining completion position when the load data D31 reaches a preset bond load. When these conditions are met, the load processing unit 61 may instruct the Z-axis position control unit 63 and the XY-axis position control unit 64 that the conditions have been met.

[0032] The trajectory processing unit 62 reads the outbound trajectory data DT1 and the return trajectory data DT2 recorded in the memory 6M. The trajectory processing unit 62 then obtains specific XYZ coordinate system values ​​from the trajectories shown in the outbound trajectory data DT1 and the return trajectory data DT2. The trajectory processing unit 62 then passes the Z coordinate system values ​​to the Z-axis position control unit 63 and the XY coordinate system values ​​to the XY-axis position control unit 64.

[0033] The Z-axis position control unit 63 passes a control signal to the Z-axis drive unit 4 to move the capillary 2 to the position corresponding to the Z coordinate system value received from the trajectory processing unit 62. Similarly, the XY-axis position control unit 64 passes a control signal to the XY-axis drive unit 5 to move the capillary 2 to the position corresponding to the X-axis coordinate system value and the Y coordinate system value received from the trajectory processing unit 62.

[0034] As previously stated, the wire bonding apparatus 1 bonds materials by pressing the bonding wire 8 against the materials to be bonded using the capillary 2. For example, the bonding load on the bonding wire 8 is generated by the reaction force received from the materials to be bonded when the capillary 2 is pressed against them. More precisely, when the materials to be bonded generate a reaction force, they undergo a predetermined deformation according to their rigidity.

[0035] For example, since the substrate electrode 911 is provided on a highly rigid substrate 91, a reaction force against the pre-set bond load of the capillary 2 can be generated with an almost negligible amount of deformation. In contrast, the overhang portion 93 can be considered a so-called cantilever beam, and therefore has lower rigidity than the substrate 91. In other words, in order to obtain a reaction force against the pre-set bond load of the capillary 2, a non-negligible amount of deformation occurs.

[0036] Figure 2 shows a magnified view of the tip of the overhang portion 93. An overhang electrode 931 for connecting the bonding wire 8 is also provided on the overhang portion 93. Figure 2 illustrates a representative point P931 that defines the position of the overhang electrode 931. As shown in Figure 2, the representative point P931 of the overhang electrode 931 when the overhang portion 93 is deformed is shifted along the direction in which the overhang portion 93 extends (X-axis direction) relative to the representative point P931 of the overhang electrode 931 when the overhang portion 93 is not deformed. The magnitude of this shift will be referred to as the shift amount G93x. Since the X-axis direction is an element that defines the drive plane DP, the shift can be said to be along the drive plane DP.

[0037] For example, as shown in Figure 3(a), if the capillary 2 is lowered along a trajectory T91 in the Z-axis direction, the point of application of the bond load PS7 at the bond completion position PB and the representative point P931 of the overhang electrode 931 will be misaligned. Furthermore, as shown in Figure 3(b), if the capillary 2 is raised along a trajectory T92 in the opposite direction to trajectory T91, the capillary 2 will interfere with the bonding wire 8, causing unintended deformation of the neck portion 82, etc.

[0038] When the deflection amount G93z of the overhang portion 93 increases, the displacement amount G93x also increases. For example, if the rigidity of the material constituting the overhang portion 93 is low, the deflection amount G93z increases. The deflection amount G93z also increases when the distance from the base of the overhang portion 93 to the representative point P931 of the overhang electrode 931 is large. The deflection amount G93z also increases when the bond load of the capillary 2 set as a bonding condition is large. The deflection amount G93z of the overhang portion 93 can increase due to various factors. When the deflection amount G93z increases, the displacement amount G93x also increases, which affects the result of the bonding operation. The result of the bonding operation is, for example, the shape of the bonding wire after joining.

[0039] This sets an acceptable value for the displacement G93x required to obtain an acceptable bonding operation result. The allowable value for the displacement G93x then limits the overhang portion 93, the length of the overhang portion 93, and the bonding load by the capillary 2.

[0040] The wire bonding apparatus 1 of this embodiment can successfully bond the bonding wire 8 to objects to be bonded, even those that undergo a significant amount of deformation due to the pressure of the capillary 2. In other words, the wire bonding apparatus 1 of this embodiment can relax conditions such as the thickness t93 of the overhang portion 93, the length L93 of the overhang portion 93, and the bonding load by the capillary 2, which are imposed in order to obtain an acceptable bonding operation result.

[0041] The wire bonding apparatus 1 moves the capillary 2 relative to the overhang electrode 931 in an adjustment direction (X-axis direction) parallel to the drive plane DP which intersects with the direction of the bond load (Z-axis direction) at the pretouch position PA, in accordance with the deformation of the overhang portion 93. Figure 4(a) shows the forward trajectory T1 followed by the capillary 2 when moving from the pretouch position PA to the bond completion position PB. In this case, at the bond completion position PB, the point of application of the bond load PS7 and the representative point P931 of the overhang electrode 931 coincide. Figure 4(b) shows the return trajectory T2 followed by the capillary 2 when moving from the bond completion position PB to the pretouch position PA. Unlike the case shown in Figure 3(b), when the capillary 2 follows the return trajectory T2, the capillary 2 does not interfere with the bonding wire 8. Therefore, no unintended deformation occurs in the neck portion 82, etc. In other words, by moving the capillary 2 in the adjustment direction, the desired bonding operation result can be obtained even when the displacement G93x is large.

[0042] <Effects of the Wire Bonding Apparatus> The wire bonding apparatus 1 includes a capillary 2 that extends in the direction of a predetermined axis A2 and joins the bonding wire 8 to the overhang portion 93 (to be joined), a bonding tool 3 that holds the capillary 2 and can move the capillary 2 in the Z-axis direction (first direction) along the predetermined axis A2 and in the X-axis direction and Y-axis direction (second direction) intersecting the Z-axis direction, and a controller 6 that controls the movement of the capillary 2 by the bonding tool 3. The controller 6 gives a control signal C6 to the bonding tool 3 and simultaneously performs a joining operation that moves the capillary 2 along the Z-axis direction and an adjustment operation that moves the capillary 2 along the X-axis direction or the Y-axis direction, while the capillary 2 is receiving a reaction force from the overhang portion 93.

[0043] The controller 6 moves the capillary 2 along the Z-axis direction in a state where the capillary 2 receives a reaction force from the overhang portion 93. According to this operation, the bonding wire 8 can be pressed against the overhang portion 93 with a desired load. Further, the controller 6 moves the capillary 2 along the X-axis direction or the Y-axis direction in parallel with the bonding operation of moving the capillary 2 along the Z-axis direction. This movement along the X-axis direction or the Y-axis direction allows the position of the capillary 2 to follow the deformation of the overhang portion 93. As a result, in wire bonding involving deformation of the overhang portion 93, the bonded bonding wire 8 can be formed into a desired shape.

[0044] When performing the operation of moving the capillary 2 in a direction away from the overhang portion 93, the controller 6 concurrently executes an adjustment operation of moving the capillary 2 in the X-axis direction or the Y-axis direction. According to this operation, the capillary 2 can be moved such that unintended deformation does not occur in the bonding wire 8 bonded to the overhang portion 93.

[0045] When performing the operation of moving the capillary 2 in a direction approaching the overhang portion 93, the controller 6 concurrently executes an adjustment operation of moving the capillary 2 in the X-axis direction or the Y-axis direction. According to this operation, even when the overhang portion 93 is deformed, the position at which the capillary 2 presses the bonding wire 8 against the overhang portion 93 can be relatively maintained.

[0046] The distance along the Z-axis direction from the pre-touch position PA to the bonding completion position PB may be larger than the distance along the X-axis direction or the Y-axis direction from the pre-touch position PA to the bonding completion position PB. According to this aspect as well, in wire bonding involving deformation of the overhang portion 93, the bonded bonding wire 8 can be formed into a desired shape.

[0047] The trajectory that the tip of the capillary 2 passes through while moving from the pre-touch position PA to the bonding completion position PB includes a straight line portion. According to this trajectory, control for moving the capillary 2 by the bonding tool can be simplified.

[0048] A trajectory that the tip of the capillary 2 passes through when moving from the pre-touch position PA to the bonding completion position PB is the same as a trajectory that the tip of the capillary 2 passes through when moving from the bonding completion position PB to the pre-touch position PA. According to this trajectory, control for moving the capillary 2 by the bonding tool can be simplified.

[0049] <Method for bonding bonding wires> Next, a method for bonding bonding wires performed by the wire bonding apparatus 1 will be described with reference to the flowchart shown in FIG. 5.

[0050] First, a ball 81 is formed at the tip of a bonding wire 8 protruding from the tip of the capillary 2 (S1: see FIG. 6(a)). This ball 81 is a so-called FAB. During this step S1, the capillary 2 is not in contact with the overhang portion 93. Also, the ball 81 is not in contact with the overhang portion 93 either. That is, the capillary 2 is not in a state of receiving a reaction force from the overhang portion 93.

[0051] Next, an operation of bringing the capillary 2 closer to the surface of the overhang portion 93 is started (S2). Specifically, the controller 6 sends a control signal to the Z-axis driving unit 4 to move the tip of the bonding tool 3 downward in the Z-axis direction. As a result, the capillary 2 held at the tip of the bonding tool 3 also moves downward in the Z-axis direction.

[0052] After starting step S2, it is determined whether or not the capillary 2 has come into contact with the surface of the overhang portion 93 (S3). When it is determined that the capillary 2 has come into contact with the surface of the overhang portion 93 (S3: YES, see FIG. 6(b)), a correction operation is started (S4: see FIG. 6(c)). The operation of moving the capillary 2 downward in the Z-axis direction continues even after the correction operation is started.

[0053] Next, the controller 6 reads the forward trajectory data DT1 (S5). Then, it moves the tip of the capillary 2 from the pretouch position PA to the bond completion position PB (S6: see Figure 6(d)). In this step S6, the controller 6 outputs a control signal C6 to the Z-axis drive unit 4 to move the capillary 2 in the -Z-axis direction (S61), and a control signal C6 to the XY-axis drive unit 5 to move the capillary 2 in the -X-axis direction (S62). The controller 6 moves the tip of the capillary 2 from the pretouch position PA to the bond completion position PB so that it follows the pre-set forward trajectory T1. The conditions for determining that the tip of the capillary 2 has reached the bond completion position can be set arbitrarily. For example, the information of the forward trajectory T1 includes X, Y, and Z coordinate values ​​indicating the joint completion position PB, and it may be determined that the joint completion position PB has been reached when the values ​​indicated by the XY axis position sensor 51 and the Z axis position sensor 41 match these coordinate values. Alternatively, a control signal may be output to move from the pretouch position PA to the X, Y, and Z coordinate values ​​indicating the joint completion position PB, and it may be determined that the joint completion position PB has been reached when this operation is completed. Furthermore, the load generated by the load sensor 31 is monitored while the capillary 2 is moved along the forward trajectory T1. It may then be determined that the joint completion position PB has been reached when the load reaches a predetermined value.

[0054] Next, the bonding operation is performed (S7: see Figure 7(a)). This step S7 is performed with the tip of the capillary 2 in the bonding completion position PB. When the tip of the capillary 2 is in the bonding completion position PB, the capillary 2 is pressing the bonding wire 8 against the overhang portion 93 with a preset bonding load. In this state, the capillary 2 may further apply ultrasonic waves to the bonding wire 8. The capillary 2 may also apply heat to the bonding wire 8.

[0055] Next, the controller 6 reads the return trajectory data DT2 (S8). The tip of the capillary 2 is moved from the bonding completion position PB to the pretouch position PA (S9: see Figure 7(b)). The controller 6 moves the tip of the capillary 2 from the bonding completion position PB to the pretouch position PA so that it follows the pre-set return trajectory T2. More specifically, in step S9, the controller 6 outputs a control signal C6 to the Z-axis drive unit 4 to move the capillary 2 in the +Z-axis direction (S91), and a control signal C6 to the XY-axis drive unit 5 to move the capillary 2 in the +X-axis direction (S92).

[0056] Then, the capillary 2 is separated from the surface of the overhang portion 93 (S10: see Figure 7(c)).

[0057] By performing steps S1 to S10 described above, the bonding wire 8 can be joined to the easily deformable overhang portion 93.

[0058] <Effects of the method for joining bonding wires> Another embodiment of the present disclosure is a method for joining bonding wires to an object to be joined using a capillary extending in the direction of a predetermined axis, comprising the steps of: setting the capillary in a state where it is receiving a reaction force from the object to be joined; performing a joining operation in parallel, moving the capillary along a first direction along the predetermined axis; and performing an adjustment operation in parallel, moving the capillary along a second direction intersecting the first direction. According to this method, similar to the wire bonding apparatus described above, in wire bonding involving deformation of the object to be joined, the joined bonding wires can be made into a desired shape.

[0059] In the above explanation, the adjustment operation to accommodate the deformation of the overhang portion 93 in the Z-axis direction was exemplified as moving the capillary 2 only in the X-axis direction. The adjustment operation may also involve moving the capillary 2 only in the Y-axis direction, or moving the capillary 2 in both the X-axis and Y-axis directions.

[0060] For example, consider a case where the longitudinal direction of the overhang portion 93 is the X-axis direction and the width direction is the Y-axis direction. When the width along the Y-axis direction is relatively small, the deformation along the Y-axis direction can be ignored, so the adjustment operation only requires moving the capillary 2 in the X-axis direction. On the other hand, as shown in Figure 8, when the width along the Y-axis direction is relatively large and the edge of the overhang portion 93 in the width direction is pressed, the overhang portion 93 undergoes torsional deformation due to the bonding load. The deformation along the Y-axis direction associated with this torsional deformation cannot be ignored. In the example in Figure 8, a displacement G93x occurs in the X-axis direction and a displacement G93y occurs in the Y-axis direction. In this case, the adjustment operation involves moving the capillary 2 in both the X-axis and Y-axis directions. In other words, the controller 6 performs the bonding operation while changing the ratio of the X-axis and Y-axis directions so that the capillary 2 follows the torsional deformation. Similarly, when the controller 6 separates the capillary 2 from the overhang portion 93, it moves the capillary 2 away from the overhang portion 93 while changing the ratio of the X-axis and Y-axis directions so that the capillary 2 follows the deformation of the overhang portion 93.

[0061] <Modifications> The wire bonding apparatus and method for joining bonding wires described herein have been explained above. However, the wire bonding apparatus and method for joining bonding wires described herein are not necessarily limited to the embodiments described above, and various modifications can be made without departing from the gist of the invention.

[0062] <Modification 1> For example, as shown in Figure 9(a), the forward path T1A that the capillary 2 travels through while moving from the pretouch position PA to the bond completion position PB may include a curved portion. This forward path T1A allows the capillary to accurately follow the deformation of the object to be bonded. The return path may also include a curved portion.

[0063] <Modification 2> For example, as shown in Figure 9(b), the forward trajectory T1A that the capillary 2 travels through while moving from the pretouch position PA to the bond completion position PB may be different from the return trajectory T2 that the capillary 2 travels through while moving from the bond completion position PB to the pretouch position PA. This operation increases the degree of freedom in setting the trajectory.

[0064] <Note> This disclosure includes the following components.

[0065] The present disclosure [1] describes a wire bonding apparatus comprising: a capillary extending in the direction of a predetermined axis and for bonding a bonding wire to a bonding object; a bonding tool for holding the capillary and for moving the capillary in a first direction along the predetermined axis and a second direction intersecting the first direction; and a controller for controlling the movement of the capillary by the bonding tool, wherein the controller provides a control signal to the bonding tool to perform in parallel a bonding operation in which the capillary is moved along the first direction and an adjustment operation in which the capillary is moved along the second direction, while the capillary is receiving a reaction force from the bonding object.

[0066] The present disclosure [2] is "the wire bonding apparatus according to [1] above, wherein the bonding operation includes an operation to move the capillary toward the object to be bonded and an operation to move the capillary toward the object to be bonded, and the controller in parallel performs an adjustment operation to move the capillary toward the second direction when the operation is to move toward the object to be bonded."

[0067] The present disclosure [3] is "the wire bonding apparatus according to [1] or [2] above, wherein the bonding operation includes an operation to move the capillary toward the object to be bonded and an operation to move the capillary toward the object to be bonded, and the controller performs in parallel an adjustment operation to move the capillary toward the second direction when the operation is to move toward the object to be bonded."

[0068] This disclosure [4] is "a wire bonding apparatus according to any one of the above [1] to [3], wherein a pretouch position in which the bonding wire is in contact with the object to be bonded and a bond completion position in which the bonding of the bonding wire to the object to be bonded is completed are defined, and the distance along the first direction from the pretouch position to the bond completion position is greater than the distance along the second direction from the pretouch position to the bond completion position."

[0069] This disclosure [5] is "a wire bonding apparatus according to any one of the above [1] to [4], wherein a pretouch position in which the bonding wire is in contact with the object to be bonded and a bond completion position in which the bonding of the bonding wire to the object to be bonded is completed are defined, and the trajectory that the tip of the capillary travels through while moving from the pretouch position to the bond completion position includes a straight portion."

[0070] This disclosure [6] is "a wire bonding apparatus according to any one of the above [1] to [5], wherein a pretouch position in which the bonding wire is in contact with the object to be bonded and a bond completion position in which the bonding of the bonding wire to the object to be bonded is completed are defined, and the trajectory that the tip of the capillary travels through while moving from the pretouch position to the bond completion position includes a curved portion."

[0071] The present disclosure [7] is a wire bonding apparatus according to any one of the above [1] to [6], wherein a pretouch position in which the bonding wire is in contact with the object to be bonded and a bond completion position in which the bonding of the bonding wire to the object to be bonded is defined, and the trajectory that the tip of the capillary travels while moving from the pretouch position to the bond completion position is the same as the trajectory that the tip of the capillary travels while moving from the bond completion position to the pretouch position.

[0072] This disclosure [8] is "a wire bonding apparatus according to any one of the above [1] to [6], wherein a pretouch position in which the bonding wire is in contact with the object to be bonded and a bond completion position in which the bonding of the bonding wire to the object to be bonded is completed are defined, and the trajectory that the tip of the capillary travels while moving from the pretouch position to the bond completion position is different from the trajectory that the tip of the capillary travels while moving from the bond completion position to the pretouch position."

[0073] The present disclosure [9] is a method for joining a bonding wire to an object to be joined using a capillary extending in the direction of a predetermined axis, comprising the steps of: putting the capillary in a state where it is receiving a reaction force from the object to be joined; performing a joining operation in parallel, which involves moving the capillary along a first direction along the predetermined axis; and performing an adjustment operation in parallel, which involves moving the capillary along a second direction intersecting the first direction.

[0074] 1...Wire bonding device, 2...Capillary, 3...Bonding tool, 6...Controller, 8...Bonding wire, 93...Overhang section (to be bonded), A2...Axis, C6...Control signal, DP...Drive plane, PA...Pre-touch position, PB...Bonding completion position, T1...Forward path, T2...Return path.

Claims

1. A wire bonding apparatus comprising: a capillary extending in the direction of a predetermined axis and for joining a bonding wire to a bonding target; a bonding tool that holds the capillary and is capable of moving the capillary in an axial direction along the predetermined axis and in a drive plane intersecting the axial direction; and a controller that controls the movement of the capillary by the bonding tool, wherein the controller provides a control signal to the bonding tool to simultaneously perform a bonding operation in which the capillary is moved along the axial direction while the capillary is receiving a reaction force from the bonding target, and an adjustment operation in which the capillary is moved along the drive plane.

2. The wire bonding apparatus according to claim 1, wherein the bonding operation includes moving the capillary toward the object to be bonded and moving the capillary toward the object to be bonded, and the controller performs an adjustment operation to move the capillary along the drive plane in parallel when the operation is moving the capillary toward the object to be bonded.

3. The wire bonding apparatus according to claim 1, wherein the bonding operation includes moving the capillary toward the object to be bonded and moving the capillary toward the object to be bonded, and the controller performs an adjustment operation to move the capillary along the drive plane in parallel when the operation is moving the capillary toward the object to be bonded.

4. A wire bonding apparatus according to claim 1, wherein a pre-touch position is defined in which the bonding wire is in contact with the object to be bonded, and a bond completion position is defined in which the bonding of the bonding wire to the object to be bonded is completed, and the distance along the axial direction from the pre-touch position to the bond completion position is greater than the distance along the drive plane from the pre-touch position to the bond completion position.

5. The wire bonding apparatus according to claim 1, wherein a pre-touch position in which the bonding wire is in contact with the object to be bonded and a bond completion position in which the bonding of the bonding wire to the object to be bonded is completed are defined, and the trajectory that the tip of the capillary travels through while moving from the pre-touch position to the bond completion position includes a straight portion.

6. The wire bonding apparatus according to claim 1, wherein a pre-touch position in which the bonding wire is in contact with the object to be bonded and a bond completion position in which the bonding of the bonding wire to the object to be bonded is completed are defined, and the trajectory that the tip of the capillary travels through while moving from the pre-touch position to the bond completion position includes a curved portion.

7. A wire bonding apparatus according to claim 1, wherein a pre-touch position is defined in which the bonding wire is in contact with the object to be bonded, and a bond completion position is defined in which the bonding of the bonding wire to the object to be bonded is completed, and the trajectory that the tip of the capillary travels while moving from the pre-touch position to the bond completion position is the same as the trajectory that the tip of the capillary travels while moving from the bond completion position to the pre-touch position.

8. A wire bonding apparatus according to any one of claims 1 to 6, wherein a pre-touch position is defined in which the bonding wire is in contact with the object to be bonded, and a bond completion position is defined in which the bonding of the bonding wire to the object to be bonded is completed, and the trajectory that the tip of the capillary travels while moving from the pre-touch position to the bond completion position is different from the trajectory that the tip of the capillary travels while moving from the bond completion position to the pre-touch position.

9. A method for joining a bonding wire to an object to be joined using a capillary extending in the direction of a predetermined axis, comprising: a step of putting the capillary in a state where it is receiving a reaction force from the object to be joined; and a step of performing in parallel a joining operation of moving the capillary along an axial direction along the predetermined axis and an adjustment operation of moving the capillary along a drive plane intersecting the axial direction.

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