JP4840118B2 - Wire bonding method and wire bonding apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To remove dirt adhering to a capillary appropriately not only in the vibration direction of the capillary but also in a direction differing from the vibration direction in a wire bonding method joining a wire to a member to be joined by a ball bonding method. <P>SOLUTION: The wire bonding method has a cleaning process for scrapping off dirt by performing vibration in a fixed direction Y while the tip of the capillary 100 is being pressed against a cleaning member 200. Further, the cleaning process comprises: a first process to be performed in a state where the direction of the capillary 100 around the axis of the capillary 100 is at the same position as that when joining the wire 40; and a second process to be performed in a state where the capillary 100 is rotated around the axis of the capillary 100 so that the direction of the capillary 100 around the axis of the capillary 100 is at a position different from that of the first process. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to a wire bonding method for bonding a wire to a member to be bonded by a ball bonding method, and a wire bonding apparatus for appropriately realizing such a wire bonding method.

  Conventionally, this type of general wire bonding method is performed by a wire bonding apparatus including a vibrator that vibrates in a certain direction and a capillary attached to the vibrator.

In this method, a wire made of Au, Cu, or the like is inserted into the capillary, and the capillary is vibrated in a certain direction with the portion of the wire led out from the capillary tip pressed against the member to be joined. By doing so, the wire is joined to the member to be joined (see, for example, Patent Document 1).
JP 2003-7756 A

  However, in such a wire bonding method, when the capillary is vibrated by pressing the wire against the member to be bonded, the surface of the member to be bonded may be rubbed and attached to the capillary.

  FIGS. 7A and 7B are diagrams showing an example of a prototype of this type of conventional wire bonding method, wherein FIG. 7A is a schematic cross-sectional view of the capillary 100, and FIG. 7B is a schematic view of the capillary 100 in FIG. FIG. 4C is a schematic plan view of the distal end portion, and FIG. 5C is a schematic cross-sectional view showing a state in which the wire 40 is joined using the capillary 100 with the dirt K attached thereto.

  In FIG. 7, a member to be bonded 30 is an electrode such as a wiring board, an IC element, and a lead frame. Then, as shown in FIGS. 7A and 7B, when wire bonding is performed on the member to be bonded 30, dirt K scraped off from the member to be bonded 30 is formed on the tip of the capillary 100. Adhere to.

  When a large amount of dirt K made of these electrode materials adheres to the tip of the capillary 100, the shape of the capillary 100 is apparently deformed by the dirt K. Then, as shown in FIG. 7C, when bonding is performed in this state, the wire 40 is also deformed, so that the wire bonding property is deteriorated.

  Therefore, the present inventor has removed the dirt attached to the tip by rubbing the tip of the capillary against the cleaning member for cleaning the tip after joining the wire to the member to be joined. Thought.

  8A and 8B are diagrams showing a cleaning process by the cleaning member 200 prototyped by the present inventor, wherein FIG. 8A is a schematic cross-sectional view, and FIG. 8B is a schematic plan view showing the tip of the capillary 100 after the cleaning process. is there. FIGS. 9A to 9C are diagrams showing the movement of the capillary 100 in the cleaning process.

  As shown in FIGS. 8 and 9, in the cleaning process, the capillary 100 is vibrated in a certain direction while the tip of the capillary 100 is pressed against the cleaning member 200. The adhered dirt K is scraped off.

  Here, the cleaning member 200 may be a separate member from the member to be joined such as a plate plated with Au, or may be an empty area on the member to be joined. After wire bonding, the capillary 100 is moved to the cleaning member 200 and rubbed.

  The vibrator 110 supports the capillary 100 and vibrates with ultrasonic waves or the like in a certain direction. FIG. 8 and FIG. 9 show this constant vibration direction Y (left-right direction in the figure). Is shown. And the vibration direction Y of this cleaning process and the vibration direction at the time of joining of a wire are the same.

  As shown in FIG. 8A, the shape of the tip of a general capillary 100 is an R surface as it goes from the center to the periphery. As shown in FIG. 8, in the cleaning process, in the vibration direction Y, the cleaning member 200 is sufficiently in contact with the tip of the capillary 100 and rubs, so that the dirt K can be effectively removed. .

  As shown in FIG. 9, the capillary 100 tilts in the vibration direction Y when the tip of the capillary 100 is in contact with the cleaning member 200 and receives a frictional force, so that the tip of the capillary 100 and the cleaning member 200 are inclined. Is due to sufficient contact.

  However, in the direction perpendicular to the vibration direction Y, the capillary 100 is not rubbed as it is tilted, and the tip of the capillary 100 and the cleaning member 200 are in slight contact with each other. Therefore, as shown in FIG. 8B, the remaining dirt K is generated in the vertical direction. In FIG. 8B, the outline of the initial dirt before cleaning is indicated by a broken line.

  The present invention has been made in view of the above problems, and in a wire bonding method for bonding a wire to a member to be bonded by a ball bonding method, not only in the vibration direction of the capillary but also in a direction different from the vibration direction. Another object of the present invention is to enable appropriate removal of dirt attached to the capillary.

In order to achieve the above object, according to the first aspect of the present invention, dirt is rubbed by vibrating in a certain direction (Y) with the tip of the capillary (100) pressed against the cleaning member (200). A cleaning step of dropping the cleaning member ( 50 ), and the cleaning step (50) with the direction of the capillary (100) around the axis of the capillary (100) being the same position as when the wire (40) is joined. ) And the first step of rotating the capillary (100) about the axis of the capillary (100), and the direction of the capillary (100) about the axis of the capillary (100) is changed to the first step. of in a state in which a position different from the process, and a second step of performing a pressing and vibration to the cleaning member (50),
The member to be joined (20) is arranged on one surface of the substrate (10), and the substrate (10) is provided with a wiring (50) to which the wire (40) is not joined, and this wiring (50). that shall use as a cleaning member, a feature.

  According to this, in performing the cleaning process, the direction of the capillary (100) with respect to the vibration direction (Y) is changed by rotating the capillary (100) about the axis in the first process and the second process. The dirt attached to the capillary (100) can be appropriately removed not only in the direction along the vibration direction (Y) but also in a direction different from the vibration direction (Y).

According to a second aspect of the present invention, in the wire bonding method of the first aspect, in the cleaning step, the ball is formed by performing ball bonding with the wire (40) on the wiring (50), thereby forming the ball. By using the wiring (50) formed with a cleaning member as a cleaning member, a vibration for scraping off the dirt by pressing the tip of the capillary (100) against the ball is performed. According to a third aspect of the present invention, in the wire bonding method according to the first aspect, in the cleaning step, primary bonding and secondary bonding by the wire (40) are performed on the wiring (50), and the secondary bonding is performed. In this embodiment, the tip of the capillary (100) is pressed against the wiring (50) to vibrate the dirt.
Here, when performing the cleaning process, the execution order of the first process and the second process may be first, but if the second process is performed after the first process is performed first. Without moving the capillary (100), it is possible to smoothly move from the wire bonding process to the cleaning process as it is. However, the first step may be performed after performing the second step first.

  In addition, whether the first step or the second step is performed first, both the first step and the second step may be performed continuously, and a wire ( 40) may be joined.

  In the second step, the capillary (100) is rotated so that the direction of the capillary (100) about the axis of the capillary (100) is 90 ° different from that when the wire (40) is joined. It is preferable.

  The wire bonding apparatus includes a vibrator (110) that vibrates in a certain direction (Y) and a capillary (100) attached to the vibrator (110), and a wire is provided inside the capillary (100). (40) is inserted and the portion of the wire (40) led out from the shaft tip of the capillary (100) is pressed against the members to be joined (20, 30), and the capillary (100) is placed in a certain direction. The wire (40) is bonded to the members to be bonded (20, 30) by vibrating (Y).

According to the ninth aspect of the present invention, in such a wire bonding apparatus, the vibrator (110) supports the capillary (100) so as to sandwich the capillary (100) with a spring force, and the spring of the vibrator (110). A capillary rotating part (120, 130) for releasing the force and rotating the capillary (100) about the axis of the capillary (100) ;
A wiring (50) to which the wire (40) is not bonded is provided on one surface of the substrate (10) on which the member to be bonded (20) is arranged, and the tip of the capillary (100) is pushed against the wiring (50). In the applied state, the capillary (100) is vibrated in a certain direction (Y) to perform a cleaning operation for scrubbing off dirt adhering to the tip of the capillary (100).
This cleaning operation is performed by first pressing and vibrating the wiring (50) in a state in which the direction of the capillary (100) around the axis of the capillary (100) is set to the same position as the bonding of the wire (40). And the behavior of
By rotating the capillary (100) about the axis of the capillary (100), wiring is performed in a state where the direction of the capillary (100) around the axis of the capillary (100) is set to a position different from the first operation. a second operation for pressing and vibration to (50), that performs a, a feature.

  According to this, the capillary (100) attached to the vibrator (110) can be rotated so as to change the direction of the capillary (100) around the capillary (100) axis. A wire bonding method having a cleaning process including the first process and the second process can be appropriately performed.

  In addition, the code | symbol in the bracket | parenthesis of each means described in the claim and this column is an example which shows a corresponding relationship with the specific means as described in embodiment mentioned later.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following drawings, parts that are the same or equivalent to each other are given the same reference numerals in the drawings for the sake of simplicity.

  FIG. 1 is a schematic cross-sectional view of an electronic device S1 according to an embodiment of the present invention. In the electronic device S1, the substrate 10 is a ceramic substrate, a printed circuit board, a lead frame, a heat sink, or the like, and an IC chip 20 as a member to be bonded is mounted on one surface of the substrate 10. The IC chip 20 is bonded to the substrate 10 with a die bond material or the like (not shown).

  This IC chip 20 is a general chip formed by forming an IC circuit using a transistor element or the like on a silicon semiconductor or the like. Further, a conductor member 30 made of Au, Cu or the like as a member to be joined is provided in the vicinity of the IC chip 20.

  The conductor member 30 is made of, for example, a lead frame separate from the substrate 10. In FIG. 1, the substrate 10 and the conductor member 30 are shown as separate members, but the substrate 10 and the conductor member 30 may be integrated. For example, the conductor member 30 may be a pad or the like provided on one surface of the substrate 10.

  The IC chip 20 and the conductor member 30 are connected by a bonding wire 40 and are electrically connected to each other via the wire 40. The bonding wire 40 is formed by wire bonding using a ball bonding method, and is made of, for example, Au or Cu.

  Further, as shown in FIG. 1, a wiring 50 to which the bonding wire 40 is not bonded, that is, a wiring 50 to which wire bonding is not performed is provided on one surface of the substrate 10. The wiring 50 is a wiring 50 for performing an inspection or passing a large current, and its surface is made of Au plating, Cu plating, or the like.

  Next, a method for forming the bonding wire 40 in the electronic device S1 of the present embodiment, that is, a wire bonding method by ball bonding will be described with reference to FIGS. FIG. 2 is a view showing a main part of a wire bonding apparatus for performing the present wire bonding method, and FIG. 3 is a step of bonding the wire 40 to the members 20 and 30 to be bonded in the present wire bonding method (wire bonding step). FIG.

  In this embodiment, the pad 21 made of aluminum or the like of the IC chip 20 is used as the primary bonding side, and the conductor member 30 is used as the secondary bonding side, and both the bonding members 20 and 30 are wire-bonded by a ball bonding method.

  The wire bonding apparatus according to the present embodiment is a ball bonding apparatus that can perform general ball bonding, and has a capillary 100 attached to a vibrator 110 that vibrates in a certain vibration direction Y by ultrasonic waves. . And the capillary 100 inserts the wire 40 in the inner hole, hold | maintains the said wire 40, and pays out the wire 40 to a front-end | tip part.

  First, as shown in FIG. 3A, in the wire 40 inserted into the capillary 100, a ball (initial ball) which is formed into a spherical shape by electric discharge machining at the tip of the portion led out from the tip of the capillary 100. 41 is formed.

  Next, the ball 41 is pressed against the pad 21 of the IC chip 20 and bonded while applying ultrasonic vibration along the vibration direction Y, and primary bonding is performed (see FIG. 3B). Thereafter, the wire 40 is drawn out from the distal end portion of the capillary 100 and drawn to the conductor member 30 (see FIG. 3C).

  Next, the wire 40 routed to the conductor member 30 is pressed against the conductor member 30 at the tip of the capillary 100 and joined while applying ultrasonic vibration along the vibration direction Y to perform secondary bonding. (See FIG. 3 (d)).

  Then, the capillary 100 is moved upward in the order shown by the arrows in FIG. 3E to disconnect the wire 40 from the conductor member 30 on the secondary bonding side. Thus, the wire bonding process in the present wire bonding method is completed.

  When the wire 40 is cut, the wire 40 protrudes from the tip of the capillary 100 and remains as a tail 42. The tail 42 is again subjected to electric discharge machining in the same manner as described above to form the ball 41. Thus, one cycle of ball bonding is completed and the next cycle is performed.

  Here, also in the wire bonding method of the present embodiment, when the capillary 40 is vibrated by pressing the wire 40 against the pad 21 or the conductor member 30 of the IC chip 20, the surfaces of the members 20 and 30 to be bonded are rubbed. As shown in FIG. 7, the parts scraped from the members to be joined 20 and 30 adhere to the capillary 100 as dirt K.

  Therefore, the wire bonding method of the present embodiment includes a cleaning process for scraping off the dirt K adhering to the tip of the capillary 100. This cleaning step is performed between the disconnection of the wire 40 shown in (e) and the formation of the ball 41 shown in (a) in FIG.

  That is, the cleaning process of the present embodiment is performed before and after the wire bonding process, but the cleaning process may be performed according to the degree of contamination of the capillary 100, that is, one cycle of the wire bonding process, that is, the above figure. 3 may be performed every one cycle of the ball bonding shown in FIG. 3, or may be performed every plural cycles.

  Here, FIG. 4 is a process diagram showing a cleaning process in the present embodiment. 4B, 4D, and 4E, the dirt K at the end of each step is indicated by hatching, and the initial outline of the dirt before cleaning is indicated by a broken line.

  As the cleaning member 200, a plate plated with Au plating or Cu plating can be used. In the electronic device S1 of the present embodiment, the wiring 50 to which the bonding wire 40 is not bonded is provided on one surface of the substrate 10, and the wiring 50 may be used as a cleaning member.

  In other words, when the tip of the capillary 100 is pressed against the cleaning member 200 and rubbed, the capillary 100 needs to sink into the cleaning member 200 to some extent. Further, after the rubbing, it is necessary that the dirt K adheres to the cleaning member 200 side.

  That is, the material of the cleaning member 200 is required to be soft enough to sink the capillary 100 and easily adhere to dirt in this kind of ball bonding. As such a cleaning member 200, one having a Brinell hardness (BHN) of about 26 to 46, specifically, one made of Au plating or Cu plating as described above is preferable.

  In the cleaning process of the present embodiment, first, after joining the members 20 and 30 to be joined by the bonding wire 40, the capillary 100 is moved onto the cleaning member 200 as shown in FIG.

  Then, with the tip of the capillary 100 pressed against the cleaning member 200, the capillary 100 is vibrated in a certain vibration direction Y by the vibrator 110, so that the dirt K attached to the tip of the capillary 100 is scraped off. At this time, in this cleaning process, rubbing on the cleaning member 200 is performed in two processes.

  First, in the first step, as shown in FIG. 4A, the capillary 100 is pushed to the cleaning member 200 in the state where the direction of the capillary 100 around the axis of the capillary 100 is the same position as when the wire 40 is joined. Apply contact and vibration. In other words, the capillary 100 is moved onto the cleaning member 200 and rubbed while maintaining the attachment state of the capillary 100 to the vibrator 110 when the wire 40 is bonded.

  By performing this first step, as shown in FIG. 4B, the dirt K in the direction along the vibration direction Y is removed at the tip of the capillary 100. However, the dirt K in the direction perpendicular to the vibration direction Y remains.

  Therefore, in the second step to be performed next, as shown in FIGS. 4C and 4D, the position of the capillary 100 around the axis of the capillary 100 is 90 ° different from the position when the wire 40 is joined. To be. That is, the capillary 100 is rotated around the axis of the capillary 100 so that the direction of the capillary 100 around the capillary 100 is at a position different from that of the first step.

  Specifically, the fixation of the capillary 100 by the vibrator 110 is once released, and the capillary 100 is rotated around the axis automatically or manually to change the direction. Note that the position different by 90 ° is not limited to being completely different by 90 °, but allows an error of about several percent.

  Accordingly, the dirt K remaining after the first step is arranged along the vibration direction Y (see FIG. 4D). In the second step, the cleaning member 200 is pressed and vibrated in a state where the direction of the capillary 100 around the capillary 100 is 90 ° different from that at the time of bonding the wire 40.

  As a result, the dirt K remaining after the first step is scraped off, and after the completion of the second step, the tip of the capillary 100 has a diameter of the capillary 100 as shown in FIG. The dirt K is removed in all directions.

  Here, the vibration power in the first step and the second step is preferably larger than the vibration power in the wire bonding step in order to remove the dirt K with certainty. For example, the vibration power in the first and second steps is set to be twice or more the vibration power in the wire bonding step.

  Thus, according to the present embodiment, since the capillary 100 is rotated about the axis and the direction of the capillary 100 with respect to the vibration direction Y is changed in the first step and the second step in performing the cleaning step. The dirt that cannot be removed in the first step can also be scraped off in the second step.

  That is, according to the cleaning process of this embodiment, the dirt K along the vibration direction Y is removed by the first process, and the dirt K along the direction different from the vibration direction Y is removed by the second process. can do. After that, if the wire 40 is bonded again using the clean capillary 100, good wire bondability can be secured.

  In the second step, the capillary 100 may be rotated around the axis of the capillary 100 so that the direction of the capillary 100 around the axis of the capillary 100 is at a position different from that when the wire 40 is joined. The rotation angle may be other than 90 ° as described above. However, in order to exert the effect of the above-described embodiment, it is preferable to rotate between approximately 45 ° and 135 °.

  Here, in performing the cleaning process, in the example shown in FIG. 4, the first process is performed after the wire bonding process, and then the second process is performed. In this case, there is no need to perform rotation for changing the direction of the capillary 100 between the first step and the wire bonding step immediately before, and the movement from the wire bonding step to the cleaning step becomes smooth.

  However, after the wire bonding step, the second step may be performed, and then the first step may be performed. In that case, after the wire bonding step, the capillary 100 is rotated as described above to perform the second step, and then the direction around the axis of the capillary 100 is the same as the wire bonding step. The first step may be performed after returning. However, in this case, the number of rotations of the capillary 100 increases.

  In addition, whether the first step or the second step is performed first, by performing both the first step and the second step in succession, in the wire bonding step performed next, the above-described FIG. Wire bonding can be performed using a clean capillary 100 as shown in FIG.

  However, a wire bonding step as shown in FIG. 3 may be performed between the first step and the second step. For example, as long as the degree of contamination of the capillary 100 is small, it is considered that the influence of the contamination K is small even if a wire bonding step is further performed between the first and second steps.

  In addition, the cleaning process of the present embodiment includes a first process and a second process, but this does not mean that the first process and the second process are repeated once each. Absent. For example, after the first step is performed twice, the second step may be performed three times.

  Here, a specific method for rotating the capillary 100 around the axis of the capillary 100 in the second step will be described with reference to FIGS. FIGS. 5A, 5B, and 5C are side views showing the rotation method in the order of steps, and FIGS. 6A, 6B, and 6C are FIGS. It is a top view corresponding to (b) and (c).

  5 and 6 show the main part of the wire bonding apparatus. Specifically, a vibrator 110 that vibrates in a certain direction and a capillary 100 attached to the vibrator 110 are provided, so that the wire bonding step shown in FIG. 3 can be performed. It is.

  Here, in the vibrator 110, the capillary 100 is interposed between the pair of sandwiching portions 111, and the capillary 100 is sandwiched by the spring force F acting between the pair of sandwiching portions 111, as in a normal wire bonding apparatus. This is what is supported (see FIG. 6A). Further, in this case, capillary rotating portions 120 and 130 for relaxing the spring force of the vibrator 110 and rotating the capillary 100 around the axis of the capillary 100 are provided.

  The capillary rotating portions 120 and 130 are configured to include a loosening shaft 120 for loosening a spring force F sandwiching the capillary 100 in the vibrator 110 and a rotating shaft 130 for rotating the capillary 100 about its axis. Here, although not shown, the loosening shaft 120 and the rotating shaft 130 are connected to a motor or the like, and both can rotate around their own axes.

  For example, after the end of the first step and before the second step, as shown in FIGS. 5A and 6A, the vibrator 110 and the capillary 100 supported by the vibrator 110 are mounted. , Move above the loosening shaft 120 and the rotating shaft 130. Here, in the vibrator 110, a hole 112 into which the tip of the loosening shaft 120 is inserted is provided between the pair of sandwiching portions 111.

  Then, as shown in FIGS. 5B and 6B, the loosening shaft 120 is inserted into the hole 112 of the vibrator 110. Here, the loosening shaft 120 has a bar shape with an elliptical cross section, and at this stage, the acting direction of the spring force F in the vibrator 110 and the minor axis direction of the loosening shaft 120 are in a parallel relationship.

  Next, as shown in FIGS. 5C and 6C, the loosening shaft 120 is rotated inside the hole 112, and the direction of the spring force F in the vibrator 110 and the loosening shaft 120 are rotated. The major axis direction is in a parallel relationship. As a result, the hole 112 is pushed and widened, the interval between both the sandwiching portions 111 of the vibrator 110 is widened, and the spring force F that sandwiches the capillary 100 in the vibrator 110 is loosened.

  In this state, by rotating the rotating shaft 130 while bringing the side surface of the rotating shaft 130 and the side surface of the capillary 100 into contact with each other, the capillary 100 rotates about the axis, and corresponds to the second step. The orientation of the capillary 100 is realized.

  After that, the spring force F is applied by rotating the loosening shaft 120 again so as to narrow the distance between the both sandwiching portions 111, and the vibrator 110 sandwiches and fixes the capillary 100. In this way, the capillary 100 can be rotated around the axis of the capillary 100 in the second step.

  Then, according to the rotation method using the wire bonding apparatus shown in FIGS. 5 and 6, since the rotation is possible without a person touching the capillary 100, the apparatus remains in operation. The capillary 100 can be rotated. In this embodiment, the timing for changing the direction of the capillary 100 is based on the correlation between the dirt and the number of bonding points.

  Here, in the wire bonding apparatus of the present embodiment, as the capillary rotation unit, in addition to those shown in FIGS. 5 and 6, the spring force of the vibrator 110 is loosened so that the capillary 100 is rotated around the axis of the capillary 100. It is not limited to the example shown in the drawing as long as it can be rotated to the right.

(Other embodiments)
Although the present invention can be applied to the wire bonding method in which the members to be bonded 20 and 30 are connected by ball bonding as described above, the wire is bonded to the surface of the members to be bonded by the ball bonding method. The present invention can also be applied when the formed wire is formed as a bump. In this case, a cleaning process may be performed after the bumps are formed.

  Further, the rotation of the capillary 100 around the axis of the capillary 100 in order to change the direction of the capillary 100 does not have to be automatically performed as shown in FIGS. The capillary 100 may be turned by the operator's hand. However, in this case, it is necessary to temporarily stop the wire bonding apparatus and stop the movement of the vibrator 110 and the capillary 100.

  Further, examples of the cleaning member 200 include a plate plated with Au or Cu, and the wiring 50 in the electronic device S1 in FIG. 1 described above. However, as long as the dirt K of the capillary 100 can be scraped off, It may be other than that. For example, a ball made of Au or Cu may be further formed by ball bonding on the plate or wiring 50 serving as the cleaning member 200, and rubbing may be performed using the ball as a cleaning member.

  Further, the member to be joined is not limited to the IC chip 20 or the conductor member 30 on the substrate 10 described above, and any member that can connect wires by ball bonding may be used.

It is a schematic sectional drawing of the electronic device which concerns on embodiment of this invention. It is a figure which shows the principal part of the wire bonding apparatus for performing the wire bonding method which concerns on the said embodiment. It is process drawing which shows the wire bonding process in the wire bonding method which concerns on the said embodiment. It is process drawing which shows the cleaning process in the wire bonding method which concerns on the said embodiment. (A), (b), (c) is a side view which shows the rotation method of a capillary in process order. (A), (b), (c) is a top view corresponding to Drawing 5 (a), (b), and (c), respectively. It is a figure which shows the wire bonding method which this inventor made as a prototype based on a prior art, (a) is a schematic sectional drawing of a capillary, (b) is a schematic plan view of the capillary front-end | tip part in (a), (c). FIG. 3 is a schematic cross-sectional view showing wire bonding using a capillary with dirt attached thereto. It is a figure which shows the cleaning process which this inventor made as an experiment, (a) is a schematic sectional drawing, (b) is a schematic plan view which shows the capillary front-end | tip part after a cleaning process. It is a figure which shows the motion of the capillary in the cleaning process shown by FIG.

Explanation of symbols

20 ... IC chip as a member to be joined, 30 ... Conductor member as a member to be joined,
40 ... bonding wire, 100 ... capillary, 110 ... vibrator,
120: A loosening shaft as a capillary rotating part,
130... Rotating shaft as a capillary rotating part 50, 200... Cleaning member,
Y: Vibration direction of the vibrator and capillary.

Claims (9)

Insert the wire (40) into the ball bonding capillary (100) attached to the vibrator (110) that vibrates in a certain direction (Y),
With the portion of the wire (40) led out from the shaft tip of the capillary (100) pressed against the members to be joined (20, 30), the capillary (100) is moved in the fixed direction (Y). In the wire bonding method in which the wire (40) is bonded to the bonded members (20, 30) by vibrating the
The capillary (100) is vibrated in the predetermined direction (Y) in a state where the tip of the capillary (100) is pressed against a cleaning member ( 50 ) for cleaning the tip. A cleaning step of scrubbing off dirt adhering to the tip of the capillary (100);
In the cleaning step, the capillary (100) is pressed against the cleaning member ( 50 ) in a state where the direction of the capillary (100) around the axis of the capillary (100) is the same position as when the wire (40) is joined. A first step of vibrating,
By rotating the capillary (100) about the axis of the capillary (100), the orientation of the capillary (100) around the capillary (100) is in a position different from that of the first step at, Bei example a second step of performing a pressing and vibration to the cleaning member (50),
The member to be joined (20) is disposed on one surface of the substrate (10), and the substrate (10) is provided with a wiring (50) to which the wire (40) is not joined,
A wire bonding method using the wiring (50) as the cleaning member . In the cleaning step, the wire (50) is ball bonded with the wire (40) to form a ball, and the wire (50) on which the ball is formed is used as the cleaning member. By
The wire bonding method according to claim 1, wherein a vibration for scraping off the dirt is performed by pressing the tip of the capillary against the ball. In the cleaning step, primary bonding and secondary bonding by the wire (40) are performed on the wiring (50), and the tip of the capillary (100) is attached to the wiring (50) in the secondary bonding. The wire bonding method according to claim 1, wherein a vibration for pressing and scraping off the dirt is performed. The wire bonding method according to any one of claims 1 to 3, wherein, in the cleaning process, the second process is performed after the first process. The wire bonding method according to any one of claims 1 to 3, wherein, in the cleaning step, the first step is performed after the second step. Wherein in the cleaning step, the first step and the wire bonding method according to any one of claims 1 to 5, characterized in that continued to both steps of the second step. The wire bonding method according to any one of claims 1 to 5 , wherein the wire (40) is joined between the first step and the second step. The second step is characterized in that the direction of the capillary (100) around the axis of the capillary (100) is at a position that differs by 90 ° from the time when the wire (40) is joined. The wire bonding method according to any one of 1 to 7 . A vibrator (110) that vibrates in a certain direction (Y), and a ball bonding capillary (100) attached to the vibrator (110);
The wire (40) was inserted into the capillary (100), and the portion of the wire (40) led out from the axial tip of the capillary (100) was pressed against the members to be joined (20, 30). In the wire bonding apparatus, in which the capillary (100) is vibrated in the predetermined direction (Y) to join the wire (40) to the member to be joined (20, 30).
The vibrator (110) supports the capillary (100) so as to be sandwiched by a spring force,
Capillary rotation parts (120, 130) that loosen the spring force of the vibrator (110) and rotate the capillary (100) about the axis of the capillary (100) ,
A wiring (50) to which the wire (40) is not bonded is provided on one surface of the substrate (10) on which the member to be bonded (20) is arranged, and the tip of the capillary (100) is connected to the wiring (50). ), And the capillary (100) is vibrated in the predetermined direction (Y) to perform a cleaning operation for scrubbing off dirt adhering to the tip of the capillary (100).
In this cleaning operation, the capillary (100) is pressed against the wiring (50) and vibrated in a state where the direction of the capillary (100) around the capillary (100) is the same position as when the wire (40) is joined. A first action of performing
By rotating the capillary (100) about the axis of the capillary (100), the orientation of the capillary (100) about the axis of the capillary (100) is set to a position different from that of the first operation The wire bonding apparatus is configured to perform a second operation of pressing and vibrating the wiring (50) .

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