A ball-bonding wire bonding apparatus and a control method thereof

Abstract

This application discloses a ball bonding wire bonding device and its control method. The ball bonding wire bonding device includes: a vertical base and a bonding head base, the bonding head base being connected to the vertical base and movable vertically relative to the vertical base; an ultrasonic transducer and a wire clamp assembly, the ultrasonic transducer and the wire clamp assembly being indirectly mounted on the bonding head base; a wedge, the wedge being connected to the ultrasonic transducer, the welding wire being clamped by the wire clamp assembly and passing through the wedge; a ignition needle, the ignition needle being connected to the vertical base, the ignition needle being used to cooperate with the wedge to complete the welding wire ball bonding, i.e., completing one welding operation; a wire cutter assembly, the wire cutter assembly being connected to the bonding head base and located on both sides of the welding wire along with the ignition needle. After one welding operation is completed, the bonding head base moves vertically upward, and after an appropriate amount of welding wire is released from the wedge, the wire cutter assembly immediately cuts the welding wire.

Description

Technical Field

[0001] This application relates to the field of semiconductor back-end packaging, and more specifically to a ball bonding wire bonding device and its control method. Background Technology

[0002] Wire bonding equipment is a key piece of equipment in the semiconductor back-end packaging field. Its core principle is to use a terminal cutter to weld metal wires between chip pads and substrate pads under conditions of heating, constant pressure, and ultrasonic output, so as to achieve electrical interconnection between the two. Therefore, the bonding in related technologies mainly includes five actions: first welding, arc running, second welding, tail leaving, and wire breaking.

[0003] In more advanced packaging fields, flip-chip technology is used to connect pads on two layers, typically employing either "ball stacking" or "vertical wire" soldering processes. Ball stacking involves simply heating balls and stacking them layer by layer to connect the pads. However, for devices with significant height differences, ball stacking is unsuitable, necessitating vertical wire soldering. Vertical wire soldering involves a first solder joint, followed by vertically extending the wire to a fixed length before using a wire clamp to break the wire. Currently, vertical wire breakage is primarily addressed by first flipping the wire during the arc initiation phase to create a stress point, then performing a "light soldering" at this stress point. Ultrasonic and pressure treatment further disrupts the stress point, and finally, the wire is broken using a wire clamp. This method is particularly complex in terms of arc initiation logic, requiring significant clamping force to prevent wire slippage, resulting in inconsistent break points and uneven vertical wire heights, severely impacting customer product quality. Summary of the Invention

[0004] The purpose of this application is to provide a ball bonding wire bonding device and its control method to achieve the stability and reliability requirements of vertical wire bonding.

[0005] To achieve the above objectives, the technical solution adopted in this application is as follows: A ball bonding wire bonding device is provided, comprising: a vertical base and a bonding head base, wherein the bonding head base is connected to the vertical base and is vertically movable relative to the vertical base; an ultrasonic transducer and a wire clamp assembly, wherein the ultrasonic transducer and the wire clamp assembly are indirectly mounted on the bonding head base; a cleaver connected to the ultrasonic transducer, wherein the welding wire is clamped by the wire clamp assembly and passes through the cleaver; a ignition needle connected to the vertical base, wherein the ignition needle is used to cooperate with the cleaver to complete the ball bonding of the welding wire, i.e., to complete one weld; and a wire cutter assembly connected to the bonding head base and positioned on both sides of the welding wire along with the ignition needle. After one weld is completed, the bonding head base moves vertically upward, and after a suitable amount of welding wire is released from the cleaver, the wire cutter assembly immediately cuts the welding wire.

[0006] As a preferred embodiment, the wire cutter assembly includes a wire cutting adjustment component, a wire cutting flat component, and a wire cutting opening and closing component. One end of the wire cutting adjustment component is connected to the bonding head base, and the other end is connected to the wire cutting flat component. One end of the wire cutting opening and closing component is connected to the wire cutting flat component, and the other end is used to cut the welding wire. The wire cutting adjustment component drives the wire cutting flat component to adjust its position, and the wire cutting flat component drives the wire cutting opening and closing component to move closer to or away from the welding wire.

[0007] As another preferred embodiment, the wire trimming adjustment assembly includes an up-and-down adjustment seat, which includes a first connecting end parallel to the bonding head base. The first connecting end has an up-and-down adjustment hole extending in the up-and-down direction. The up-and-down adjustment seat is connected to the bonding head base by an up-and-down adjustment seat locking pin passing through the up-and-down adjustment hole. Adjusting the position of the up-and-down adjustment seat locking pin within the up-and-down adjustment hole adjusts the position of the up-and-down adjustment seat relative to the bonding head base in the up-and-down direction.

[0008] Further preferably, the up-down adjustment seat also includes a second connecting end for connecting with the wire-cutting flat assembly. The second connecting end is inclined relative to the first connecting end, and the wire-cutting flat assembly can move left and right relative to the second connecting end. The wire-cutting adjustment assembly also includes a left-right adjustment seat, which includes a left-right adjustment knob, a knob buckle, and a knob locking pin. The knob locking pin passes through the knob buckle and connects to the side wall of the second connecting end. The left-right adjustment knob passes through the knob buckle and connects to the wire-cutting flat assembly. By rotating the left-right adjustment knob, the left-right movement adjustment of the wire-cutting flat assembly relative to the up-down adjustment seat can be achieved.

[0009] Further preferably, the wire-cutting flat wire assembly includes: a fixed end for connecting to the second connecting end of the upper and lower adjusting seat; a movable end for connecting to the wire-cutting opening and closing assembly; a flat wire connecting plate and multiple sets of spring plates, wherein the flat wire connecting plate is connected to the fixed end of the wire-cutting flat wire via one set of spring plates, and the flat wire connecting plate is connected to the movable end of the wire-cutting flat wire via another set of spring plates; and a driving assembly, which is sandwiched between the fixed end and the movable end of the wire-cutting flat wire and is drivenly connected to the movable end of the wire-cutting flat wire. The driving assembly drives the movable end of the wire-cutting flat wire to move, causing the multiple sets of spring plates to deform, thereby completing the movement of the movable end of the wire-cutting flat wire towards or away from the welding wire.

[0010] Further preferably, the wire-cutting flat-four assembly also includes a reset member, one end of which is connected to the movable end of the wire-cutting flat-four, and the other end is connected to the drive assembly; wherein, when the drive assembly removes the driving force, the movable end of the wire-cutting flat-four is reset through the reset member.

[0011] Preferably, the wire-cutting opening and closing assembly includes: a ceramic plate holder, one end of which is connected to the movable end of the wire-cutting flat blade; a piezoelectric ceramic plate connected to the main body of the ceramic plate holder; a stationary wire-cutting arm connected to the ceramic plate holder; a movable wire-cutting arm connected to the stationary wire-cutting arm via a switch top post, the switch top post abutting against the piezoelectric ceramic plate; and an elastic element, one end of which is connected to the stationary wire-cutting arm and the other end to the movable wire-cutting arm. The piezoelectric ceramic plate deforms at its end to open the switch top post, which in turn drives the movable wire-cutting arm away from the stationary wire-cutting arm. When the wire-cutting opening and closing assembly moves down to the lower end of the blade tip, the piezoelectric ceramic plate closes, and the movable wire-cutting arm rebounds via the elastic element to approach the stationary wire-cutting arm, completing the wire-cutting action.

[0012] Preferably, the distance between the wire shearing arm and the welding wire is set to between 1 / 3 and 1 / 2 of the welding wire diameter.

[0013] Furthermore, this application also provides a control method for a ball bonding wire bonding device. This control method is applicable to any of the ball bonding wire bonding devices described above. The control method includes: Step S1: Controlling the wire cutter assembly to move above the tip of the wedge, the wedge guiding the welding wire and cooperating with the ignition needle to complete the ball-burning operation; Step S2: The bonding head base drives the wedge to move vertically downwards, pressing the burned welding wire onto the lower bonding pad, while the ultrasonic transducer outputs ultrasonic energy to complete the welding; Step S3: After welding is completed at the end of the welding wire, the bonding head base rises vertically, releasing a pre-set length of welding wire through the wedge; Step S4: Driving the wire cutter assembly to cut the welding wire at the pre-set length position of the vertical wire; Step S5: After the wire is cut, the wire clamp assembly opens, the bonding head base resets as a whole, completing the wire cutting process for a single vertical wire welding operation, preparing for the next cycle.

[0014] Furthermore, step S4 also includes step S41: after welding is completed and the height of the welding wire is reserved, the wire cutter assembly cuts the welding wire to form a cutting depth of 80%-90% of the welding wire diameter; step S42: the wire clamp assembly closes and clamps the welding wire so that it moves vertically upward with the bonding head base, and the welding wire is broken by using the weak point formed by the wire cut.

[0015] Compared with the prior art, the beneficial effects of this application are as follows:

[0016] The wire cutter assembly is designed to stabilize wire breakage during vertical wire welding by the wire bonding device, thereby improving welding reliability. The wire cutter assembly is connected to the bonding head base and can move vertically synchronously with the bonding head. This ensures that the wire cutting position always maintains a precise correspondence with the reserved height of the welding wire and the position of the cutting blade during vertical wire welding, avoiding wire cutting deviation caused by relative displacement and improving the continuity of wire cutting and subsequent wire breaking actions.

[0017] The wire cutter and the ignition needle are set on opposite sides of the welding wire. This allows the ignition needle to complete the burning process independently without being blocked or affected by the wire cutter. It also reduces spatial conflicts between components when the wire cutter cuts the welding wire, thus improving the stability of the device. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the wire cutter assembly in the wire cutting position of a ball bonding wire bonding device.

[0019] Figure 2 This is a schematic diagram of the structure of a ball-bonding wire bonding device when the welding wire is in the ignition state.

[0020] Figure 3 This is a schematic diagram of the wire cutter adjustment assembly.

[0021] Figure 4This is a schematic diagram of the four components of a wire cutter.

[0022] Figure 5 This is a schematic diagram of the opening and closing assembly of the wire cutter.

[0023] Figure 6 This is a structural diagram showing the position of the blade in the opening and closing assembly of a wire cutter.

[0024] Figure 7 for Figure 6 A magnified view of a portion of point A in the middle.

[0025] In the diagram: 1. Ball bonding wire bonding device; 2. Welding wire; 10. Vertical base; 20. Bonding head base; 30. Ultrasonic transducer; 40. Wire clamp assembly; 50. Cleaver; 60. Ignition needle; 70. Wire cutter assembly; 80. Flat four-module one;

[0026] 71. Wire trimming adjustment assembly; 711. Up-down adjustment seat; 712. First connecting end; 713. Second connecting end; 714. Up-down adjustment hole; 715. Up-down adjustment seat locking pin; 716. Left-right adjustment seat; 7161. Left-right adjustment knob; 7162. Knob buckle; 7163. Knob locking pin; 717. Left-right adjustment seat locking pin;

[0027] 72. Wire cutting flat plate assembly; 721. Wire cutting flat plate fixed end; 722. Wire cutting flat plate movable end; 723. Flat plate connecting plate; 724. Spring sheet; 725. Drive assembly; 7251. Motor stator; 7252. Motor mover; 7253. Stator locking seat one; 7254. Stator locking seat two; 7255. Limiting ceramic ball; 7256. Spring adjusting screw; 726. Reset component; 7271. Locking seat one fixing screw; 7272. Locking seat two fixing screw; 728. Spring sheet pressure plate; 7281. Pressure plate locking nail; 729. Alloy steel limit block;

[0028] 73. Wire cutting opening and closing assembly; 731. Ceramic plate holder; 7311. Ceramic plate holder locking pin; 732. Piezoelectric ceramic plate; 733. Wire cutting stationary arm; 7331. Wire cutting stationary arm locking pin; 7332. Height adjustment hole; 734. Wire cutting moving arm; 735. Elastic element; 736. Switch top post; 7361. Top post locking screw; 737. Switch fulcrum post; 738. Ceramic plate pressure plate; 739. Pressure plate locking screw; 740. Shearing force adjusting nut; 741. Shearing force adjusting screw; 742. Nut locking screw; 743. Blade. Detailed Implementation

[0029] The present application will be further described below with reference to specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0030] In the description of this application, it should be noted that the directional terms such as "center", "lateral", "longitudinal", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", and "counterclockwise" indicate the orientation and positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. They should not be construed as limiting the specific protection scope of this application.

[0031] It should be noted that the terms "first," "second," etc., in the specification and claims of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0032] The terms “comprising” and “having”, and any variations thereof, in the specification and claims of this application are intended to cover non-exclusive inclusion, for example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product, or device.

[0033] In a preferred embodiment, see Figures 1 to 7 This application provides a ball bonding wire bonding device 1, comprising: a vertical base 10, a bonding head base 20, the bonding head base 20 being connected to the vertical base 10 and movable vertically relative to the vertical base 10; an ultrasonic transducer 30, a wire clamp assembly 40, the ultrasonic transducer 30 and the wire clamp assembly 40 being indirectly mounted on the bonding head base 20; and a wedge 50, the wedge 50 being connected to the ultrasonic transducer 30, and the welding wire 2 being clamped by the wire clamp assembly 40 and passing through the wedge 50. 0. Setting; Ignition needle 60, which is connected to the vertical base 10. The ignition needle 60 is used to work with the cutting blade 50 to complete the welding of the welding wire 2, that is, to complete one welding; Wire cutter assembly 70, which is connected to the bonding head base 20 and is located on both sides of the welding wire 2 along with the ignition needle 60. After one welding is completed, the bonding head base 20 moves vertically upward, and after the cutting blade 50 releases an appropriate amount of welding wire 2 and the vertical height of the welding wire 2 is determined, the wire cutter assembly 70 then cuts the welding wire 2.

[0034] Specifically, the vertical base 10 in this application is a Z-axis base, where Z-axis refers to... Figure 1 and Figure 2In the vertically upward direction, the vertical base 10 is fixedly set. The bonding head base 20 and the vertical base 10 can be connected by one or more of the following structures: roller, track, etc., so that the bonding head base 20 can move relative to the vertical base 10 in the vertical direction. The bonding head base 20 extends with a long support arm to connect the wire clamp assembly 40. The wire clamp assembly 40 is used for the welding wire 2 to pass through and can be used to clamp the tail end of the welding wire 2. The wire clamp assembly 40 and the ultrasonic transducer 30 are spaced apart, and the ultrasonic transducer 30 is connected to the bonding head base 20 through the parallelogram module 80. The parallelogram module 80 is specifically a parallelogram structure. One end of it is fixedly installed on the bonding head base 20, and the other end is a movable end. The movable end is equipped with the ultrasonic transducer 30 and the cutting blade 50, which move up and down together. Specifically, the constant bonding force acting on the welding point can be output through hinge deformation and motor power compensation.

[0035] The ignition needle 60 is fixed on the vertical base 10 and does not move up and down with the bonding head base 20. Before the first weld, when the wire needs to be heated, the cutting blade 50 first moves down to the set height, and the high voltage discharge of the ignition needle 60 heats the welding wire 2. Then the bonding head base 20 and the cutting blade 50 move down to the welding surface to complete the first weld. The wire clamp assembly 40 is fixed on the bonding head base 20 and moves up and down with the bonding head. Its main function is to break the metal wire after the wire cutter assembly 70 has completed the wire cutting action of the welding wire 2, thereby completing the welding of a single wire.

[0036] Specifically, the wire cutter assembly 70 is used to stabilize wire breakage during vertical wire welding of the welding wire 2 by the wire bonding device, thereby improving welding reliability. The wire cutter assembly 70 is connected to the bonding head base 20 and can move vertically synchronously with the bonding head. This ensures that the wire cutting position always maintains a precise correspondence with the reserved height of the welding wire 2 and the position of the cutting blade 50 during vertical wire welding, avoiding wire cutting deviation caused by relative displacement and improving the continuity of wire cutting and subsequent wire breaking actions. The wire cutter and the ignition needle 60 are set on opposite sides of the welding wire 2, allowing the ignition needle 60 to independently complete the ball-burning operation without being obstructed or affected by the wire cutter, while also allowing the wire cutter to cut the welding wire 2, reducing the gap between components. The wire cutter is integrated with the wire clamp assembly 40 and the splitter 50, which shortens the action distance from cutting the wire to breaking the wire clamp. This makes the weak point formed by cutting the wire more evenly stressed during the breaking process, effectively preventing the welding wire 2 from "flying" or bending, ensuring the straightness and consistency of the vertical wire welding, and thus improving the welding reliability. It is preferably suitable for alloy wires with a diameter of 50um or more. The wire cutter assembly 70 is integrated into the bonding head base 20, eliminating the need for an additional independent drive mechanism to coordinate its positional relationship with the bonding head. This reduces complex transmission components, lowers the device size and the risk of failure, and facilitates the synchronous control of the action sequence of the wire cutter, wire clamp and bonding head through a unified control module.

[0037] As a preferred embodiment, the wire cutter assembly 70 includes a wire cutting adjustment assembly 71, a wire cutting flat assembly 72, and a wire cutting opening and closing assembly 73. One end of the wire cutting adjustment assembly 71 is connected to the bonding head base 20, and the other end is connected to the wire cutting flat assembly 72. One end of the wire cutting opening and closing assembly 73 is connected to the wire cutting flat assembly 72, and the other end is used to cut the welding wire 2. The wire cutting adjustment assembly 71 drives the wire cutting flat assembly 72 to adjust its position, and the wire cutting flat assembly 72 drives the wire cutting opening and closing assembly 73 to move closer to or away from the welding wire 2.

[0038] in, Figure 2 This is a schematic diagram of the ball bonding wire bonding device 1 during the ignition process of the welding wire 2. After the welding wire 2 has finished igniting and burning the ball, see [the diagram]. Figure 1 The welding wire 2 is cut using the wire cutter assembly 70.

[0039] As another preferred option, see Figure 3The wire trimming adjustment assembly 71 includes an upper and lower adjustment seat 711. The upper and lower adjustment seat 711 includes a first connecting end 712 parallel to the bonding head base 20. The first connecting end 712 has an upper and lower adjustment hole 714 extending in the upper and lower direction. The upper and lower adjustment seat 711 is connected to the bonding head base 20 by passing through the upper and lower adjustment hole 714 via an upper and lower adjustment seat locking pin 715. The position of the upper and lower adjustment seat locking pin 715 in the upper and lower adjustment hole 714 is adjusted to adjust the position of the upper and lower adjustment seat 711 relative to the bonding head base 20 in the upper and lower direction.

[0040] Further preferably, the up-down adjustment seat 711 also includes a second connecting end 713 for connecting with the wire trimming and flattening assembly 72. The second connecting end 713 is inclined relative to the first connecting end 712, and the wire trimming and flattening assembly 72 can move left and right relative to the second connecting end 713. The wire trimming adjustment assembly 71 also includes a left-right adjustment seat 716, which includes a left-right adjustment knob 7161, a knob latch 7162, and a knob locking pin 7163. The knob locking pin 7163 passes through the knob latch 7161. 62 is connected to the side wall of the second connecting end 713. The left and right adjustment knob 7161 passes through the knob buckle 7162 and is connected to the wire cutting flat four-part component 72. By rotating the left and right adjustment knob 7161, the left and right movement adjustment of the wire cutting flat four-part component 72 relative to the upper and lower adjustment seat 711 can be realized. When the wire cutting flat four-part component 72 is adjusted to a suitable position by the left and right adjustment knob 7161, the left and right adjustment knob 7161 is locked and fixed by the left and right adjustment seat locking pin 717 cooperating with the second connecting end 713.

[0041] Specifically, the up-down adjustment seat 711 is used to control the overall up-down movement adjustment of the wire cutter assembly 70 within a large range. Similarly, the left-right movement of the wire cutter assembly 72 relative to the up-down adjustment seat 711 is also used to control the overall left-right movement adjustment of the wire cutter assembly 70 within a large range. The up-down adjustment hole 714 is specifically a through hole with an elongated opening shape. The up-down adjustment seat 711 is fixedly connected to the bonding head base 20 by the up-down adjustment seat locking pin 715. The up-down adjustment seat locking pin 715 is located at different positions within the up-down adjustment hole 714, thereby adjusting the different height positions of the up-down adjustment seat 711 relative to the bonding head base 20 in the up-down direction.

[0042] See Figure 3 and Figure 4Since the second connecting end 713 is connected to the wire trimming flat assembly 72, and the wire trimming flat assembly 72 includes a wire trimming flat fixed end 721 and a wire trimming flat movable end 722, the second connecting end 713 in the upper and lower adjusting seat 711 is specifically connected to the wire trimming flat fixed end 721. The second connecting end 713 of the upper and lower adjusting seat 711 has a trapezoidal groove, and a trapezoidal protrusion is provided on the wire trimming flat fixed end 721. The trapezoidal groove of the second connecting end 713 extends in the left and right direction. When the trapezoidal protrusion in the wire trimming flat fixed end 721 is inserted into the trapezoidal groove of the second connecting end 713, the wire trimming flat fixed end 721 can move relative to the upper and lower adjusting seat 711 in the left and right direction.

[0043] Furthermore, the second connecting end 713 is connected to the left and right adjusting seat 716 on the same side as the wire cutting flat four-way fixing end 721. The left and right adjusting seat 716 is used to adjust and fix the position of the wire cutting flat four-way component 72 relative to the up and down adjusting component. Preferably, the knob locking pin 7163 passes through the knob buckle 7162 to be fixedly connected to the side of the up and down adjusting seat 711. At this time, the knob buckle 7162 is fixedly set relative to the up and down adjusting seat 711 by the fastening of the knob locking pin 7163. The end of the left and right adjusting knob 7161 is fixedly connected to the wire cutting flat four-way fixing end 721. The connection between the left and right adjusting knob 7161 and the knob buckle 7162 can be provided with a threaded engagement structure. Then, by turning the left and right adjusting knob 7161, the position of the knob relative to the knob buckle 7162 can be adjusted, thereby driving the position of the wire cutting flat four-way component 72 relative to the up and down adjusting seat 711 to adjust.

[0044] For further optimization, see [link to relevant documentation]. Figure 4 In the wire cutting flat wire assembly 72, the fixed end 721 of the wire cutting flat wire is used to connect with the second connecting end 713 of the upper and lower adjusting seat 711; the movable end 722 of the wire cutting flat wire is used to connect with the wire cutting opening and closing assembly 73; the flat wire connecting plate 723 and multiple sets of spring plates 724 are connected, with one set of spring plates 724 connecting the flat wire connecting plate 723 and the movable end 722 of the wire cutting flat wire through another set of spring plates 724; the driving assembly 725 is sandwiched between the fixed end 721 and the movable end 722 of the wire cutting flat wire and is drivenly connected to the movable end 722 of the wire cutting flat wire; wherein, by driving the movable end 722 of the wire cutting flat wire through the driving assembly 725, the multiple sets of spring plates 724 deform to complete the movement of the movable end 722 of the wire cutting flat wire towards or away from the welding wire 2.

[0045] Specifically, multiple sets of spring plates 724 and flat four-way connecting plates 723 are connected to both sides of the fixed end 721 and the movable end 722 of the wire shearing flat four-way connector. Preferably, four sets of spring plates 724 are provided, which are high fatigue strength spring plates 724 to achieve a long service life. One flat four-way connecting plate 723 and two sets of spring plates 724 are provided on one side of the fixed end 721 and the movable end 722 of the wire shearing flat four-way connector. A spring plate pressure plate 728 is also provided on the top of the spring plate 724. The spring plate pressure plate 728 and the spring plate 724 are connected to the fixed end 721, the flat four-way connecting plate 723 and the movable end 722 of the wire shearing flat four-way connector through the pressure plate locking nail 7281. Therefore, through the arrangement of the spring plates 724 on both sides of the fixed end 721 and the movable end 722 of the wire shearing flat four-sided ... Figure 1 and Figure 2 Structural changes of the four components of the middle shear line 72.

[0046] The movable end 722 of the wire shearing flathead is driven by a drive assembly 725, which includes a motor stator 7251 and a motor mover 7252. The motor stator 7251 is covered by a stator locking seat 1 7253 and a stator locking seat 2 7254. The stator locking seat 1 7253 is fixedly connected to the fixed end 721 of the wire shearing flathead through a locking seat 1 fixing screw 7271. The stator locking seat 2 7254 is fixedly connected to the stator locking seat 1 7253 through a locking seat 2 fixing screw 7272. Thus, the motor stator 7251 is clamped and fixed by the stator locking seat 1 7253 and the stator locking seat 2 7254. The motor mover 7252 is connected to the movable end 722 of the wire shearing flathead and drives the movable end 722 of the wire shearing flathead to move.

[0047] Further preferably, the wire-cutting flat-four assembly 72 also includes a reset member 726. One end of the reset member 726 is connected to the movable end 722 of the wire-cutting flat-four, and the other end is connected to the drive assembly 725. When the drive assembly 725 removes the driving force, the reset member 726 drives the movable end 722 of the wire-cutting flat-four to reset. Specifically, the reset member 726 is a reset spring, which, through its extension and retraction reset action, drives the movable end 722 of the wire-cutting flat-four, which is in the shearing position, back to its original position. See [reference needed]. Figure 4 One end of the return spring is connected to the movable end 722 of the wire shearing plate, and the other end is connected to the spring adjusting screw 7256 provided on the locking seat. The spring adjusting screw 7256 can be rotated to adjust the height position of the screw relative to the locking seat, thereby determining the position of the movable end 722 of the wire shearing plate after the return spring is reset.

[0048] The stator locking seat 7254 is also provided with limiting ceramic balls 7255 on both sides. The wire cutter flat four movable end 722 is also provided with alloy steel limiting blocks 729 on both sides of the limiting ceramic balls 7255. When the wire cutter flat four movable end 722 moves under the drive of the drive assembly 725, the alloy steel limiting blocks 729 move synchronously with the movable end until they contact the limiting ceramic balls 7255 on the stator locking seat 7254. The rigid contact between the two blocks the movable end from continuing to move, thereby precisely controlling the maximum displacement of the wire cutter flat four movable end 722 and avoiding collisions or interference between the wire cutter assembly 70 and other components, such as the splitter 50 and the welding wire 2, due to excessive drive. Therefore, the repeatability of the wire cutter's up and down movements is ensured by the two sets of hard limiters mentioned above. Both the upper and lower limiters are point contacts. This structure can reduce the parallelism requirement between the moving end and the fixed end during installation, while also ensuring the uniqueness of the hard limit point. At the same time, the choice of ceramic balls and alloy steel limit blocks 729 is also based on the consideration of a long service life for the wire cutter mechanism.

[0049] Meanwhile, by using the limiting ceramic ball 7255 and the alloy steel limiting block 729 to determine the fixed limiting point, it is ensured that the moving end 722 of the wire cutter can reach the same limit position every time it moves, so that the cutting position, angle and other parameters of the wire cutter assembly 70 remain stable, avoiding the impact of stroke deviation on the cutting depth and accuracy, and thus ensuring the consistency of vertical wire welding.

[0050] Furthermore, the tilt angle of the wire cutting flat component 72 in the wire cutter assembly 70 is the angle between the vertical movement direction of the wire cutter assembly 70 and the horizontal plane. The selection of this angle takes into account the wire cutter's avoidance of the wire bonding area, while also taking into account the welding of devices with certain cavity depth requirements. Therefore, this application document preferably sets the tilt angle to 45-60 degrees.

[0051] Preferred, see Figure 5The wire-cutting opening and closing assembly 73 includes: a ceramic plate holder 731, one end of which is connected to the movable end 722 of the wire-cutting flat plate; a piezoelectric ceramic plate 732, which is connected to the main body of the ceramic plate holder 731; a wire-cutting stationary arm 733, which is connected to the ceramic plate holder 731; a wire-cutting movable arm 734, which is connected to the wire-cutting stationary arm 733 via a switch top post 736, the switch top post 736 abutting against the piezoelectric ceramic plate 732; and an elastic element 735. One end of the elastic element 735 is connected to the wire-cutting stationary arm 733, and the other end is connected to the wire-cutting movable arm 734. The piezoelectric ceramic sheet 732 deforms at its end to open the switch top post 736, which in turn drives the wire-cutting movable arm 734 away from the wire-cutting stationary arm 733. When the wire-cutting opening and closing assembly 73 moves down to the lower end of the blade tip of the cutting blade 50, the piezoelectric ceramic sheet 732 closes, and the wire-cutting movable arm 734 returns to its original position through the elastic element 735 to approach the wire-cutting stationary arm 733 and complete the wire-cutting action of the welding wire 2.

[0052] Specifically, the ceramic plate holder 731 has a slot for embedding the piezoelectric ceramic plate 732. A ceramic plate pressure plate 738 is provided at the end of the piezoelectric ceramic plate 732 away from the shearing stationary arm 733 for fixing and limiting its position. The ceramic plate pressure plate 738 is fixedly connected to the ceramic plate holder 731 by a pressure plate locking screw 739. Simultaneously, the ceramic plate holder 731 and the movable end 722 of the shearing flat arm are fixedly connected by a ceramic plate holder locking screw 7311. Thus, the ceramic plate holder 731 is positioned relative to the movable end of the shearing flat arm. 722 is a fixed setting. The shearing arm 733 has a height adjustment hole 7332, which has a certain adjustment stroke. The shearing arm 733 is fixed to the ceramic plate holder 731 by passing the shearing arm locking pin 7331 through the height adjustment hole 7332. The position of the shearing arm 733 can be adjusted within a small range by adjusting the position of the shearing arm locking pin 7331 relative to the height adjustment hole 7332. The adjustment position must ensure that the shearing arm 733... The shearing end of 3 extends out of the ceramic plate holder 731 to avoid interference with the shearing by the ceramic plate holder 731; a switch fulcrum post 737 is also protruding on the shearing stationary arm 733. The switch fulcrum post 737 is a type of two pins with a certain taper at the head. The shearing arm 734 is positioned by the switch fulcrum post 737, thereby aligning and cooperating with the shearing stationary arm 733. Due to the setting of the switch fulcrum post 737, the shearing arm 734 can open a certain gap relative to the shearing stationary arm 733; the switch top post 736 passes through... The shearing arm 734 and the shearing stationary arm 733 abut against the piezoelectric ceramic plate 732. The switch top post 736 and the shearing arm 734 are fixedly engaged by the top post locking screw 7361. When the switch top post 736 is opened by the end deformation of the piezoelectric ceramic plate 732, the shearing arm 734 can be driven to move with the movement of the switch top post 736. The shearing action of the shearing assembly is completed by the switch top post 736 moving away from and closer to the shearing stationary arm 733.

[0053] The elastic element 735 is specifically a compression spring, with its two ends connected to the wire-cutting stationary arm 733 and the wire-cutting movable arm 734, respectively. When the switch top post 736 drives the wire-cutting movable arm 734 away from the wire-cutting stationary arm 733, the compression spring is stretched to accumulate elastic potential energy. When the piezoelectric ceramic plate 732 closes and removes the force on the switch top post 736, the wire-cutting movable arm 734 can move closer to the wire-cutting stationary arm 733 as the compression spring returns to its original position, thus completing the cutting action.

[0054] The compression spring also contains a shear force adjusting screw 741. The shear force of the wire cutter assembly 70 can be set by changing the spring force applied to the wire cutting arm 734. The shear force parameters used are different for metal wires of different materials and diameters, and need to be distinguished. Specifically, the end of the shear force adjusting screw 741 has a thread, which is screwed onto the wire cutting stationary arm 733. The arm and stationary arm can be connected and fitted together by locking the two switch fulcrum pins 737 and the shear force adjusting screw 741. The other end of the shear force adjusting screw 741 is provided with a shear force adjusting nut 740. The shear force adjusting nut 740 is fixed to the compression spring by a nut locking screw 742. By adjusting the position of the shear force adjusting nut 740 relative to the shear force adjusting screw 741, the amount of elastic potential energy that can be accumulated after the compression spring is deformed is determined. The shorter the distance between the shear force adjusting nut 740 and the shearing stationary arm 733, the greater the elastic potential energy accumulated after the compression spring is deformed, and the stronger the shearing force generated by the shearing arm 734 after springback reset. Similarly, the greater the distance between the shear force adjusting nut 740 and the shearing stationary arm 733, the stronger the shearing force generated by the shearing arm 734 after springback reset.

[0055] Therefore, in a specific shear force adjustment process, first loosen the locking screw 742 of the shear force adjusting nut 740, and rotate the shear force adjusting nut 740 to change the compression amount of the compression spring. After the adjustment is completed, tighten the locking screw 742. The empirical value of the shear force is generally obtained by conducting offline shear tests on metal wires of different materials and diameters.

[0056] See also Figure 2 In the wire cutter assembly 70, the normal position of the wire cutting end is above the tip of the chopper 50 and at a certain distance from the chopper 50. Only when wire cutting is required will the wire cutter assembly 70 be moved below the tip of the chopper 50 by the up-down displacement mechanism, namely the wire cutting flat assembly 72. After the wire cutting is completed, the elastic element 735 in the wire cutting flat assembly 72 will immediately reset the wire. This ensures that the wire cutter assembly 70 will not interfere with the ignition needle 60 when the bonding head moves up and down, and also takes into account the feasibility of the bonding head for welding devices with a certain cavity depth.

[0057] Preferably, by adjusting the wire cutting adjustment component 71 in conjunction with the wire cutting flat component 72, the wire cutter component 70 can be adjusted in three degrees of freedom: up and down, front and back, and left and right. Among these, the adjustment in the left and right direction is particularly important for the wire cutter. If the distance between the wire cutting stationary arm 733 and the welding wire 2 is too far, the wire cutting movable arm 734 will "bend" the vertical welding wire 2 when it closes, affecting the overall welding straightness. However, if the distance between the two is negative, it will collide with the welding wire 2 to be cut when the wire cutter component 70 moves down, affecting the normal welding process. Therefore, preferably, the distance between the wire cutting stationary arm 733 and the welding wire 2 is set to between 1 / 3 and 1 / 2 of the diameter of the welding wire 2.

[0058] Further, see Figure 6 and Figure 7 The wire cutting arm 734 is provided with a blade 743. In this application, the blade 743 preferably adopts a single blade structure. Therefore, in this application, the side of the wire cutting arm 733 near the wire cutting arm 734 is a flat surface, while the wire cutting arm 734 is a sharp blade 743. In addition, the cutting end of the blade 743 on the wire cutting arm 734 is the lowest point of the arm. The cut-off part on the right side of the blade 743 is to prevent the wire cutter assembly 70 from hitting the top of the previously welded vertical wire during the downward movement, which would affect the straightness after welding.

[0059] Therefore, the ball bonding wire bonding device 1 in this application is equipped with a wire cutter assembly 70, which greatly optimizes the vertical wire welding. It not only solves the instability of the current method of simply relying on bending stress points and the large load of the wire clamp to break the wire, but also simplifies the arc logic during vertical wire welding. Through the wire cutting action, the wire clamp can easily break the welding wire 2, and at the same time, it greatly improves the consistency of the arc shape and wire height of vertical wire welding, which is crucial for improving the quality of customer products.

[0060] Meanwhile, the wire cutter assembly 70 provided in this application has a simple structure and low manufacturing cost, so the original ball bonding machine can be upgraded to a device for vertical wire bonding without adding too much extra cost; moreover, the reset action and shearing force application of the wire cutter assembly 70 are achieved by springs, without the need for additional power or air circuits, which also reduces the failure rate to a certain extent and ensures the stable operation of wire bonding.

[0061] Furthermore, this application also provides a control method for a ball bonding wire bonding device 1. This control method is applicable to any of the ball bonding wire bonding devices 1 described above. The control method includes: Step S1: Controlling the wire cutter assembly 70 to move above the tip of the cleaver 50, the cleaver 50 guides the welding wire 2 to cooperate with the ignition needle 60 to complete the ball-bonding operation; Step S2: The bonding head base 20 drives the cleaver 50 to move vertically downwards, pressing the ball-bonded welding wire 2 onto the lower bonding layer. On the plate, the ultrasonic transducer 30 outputs ultrasonic energy to complete the welding; Step S3: After the welding of the end of the welding wire 2 is completed, the bonding head base 20 rises vertically and the welding wire 2 of the preset length of the vertical line is released through the cutting blade 50; Step S4: Drive the wire cutter assembly 70 to cut the welding wire 2 at the preset length position of the vertical line; Step S5: After the wire is cut, the wire clamp assembly 40 opens and the bonding head base 20 is reset as a whole, completing the wire cutting process of a single vertical line welding, and preparing for the next cycle.

[0062] Furthermore, step S4 also includes step S41: after welding is completed and the vertical height of welding wire 2 is reserved, the wire cutter assembly 70 cuts the welding wire 2 to form a cutting depth of 80%-90% of the wire diameter of welding wire 2; step S42: the wire clamp assembly 40 closes and clamps the welding wire 2 so that it moves vertically upward with the key head base 20, and the welding wire 2 is broken by using the weak point formed by the wire cut.

[0063] Specifically, under normal circumstances, after the welding is completed and the vertical line height is predetermined, the wire cutter does not completely cut the metal wire. Instead, it cuts to a depth of 80-90% of the wire diameter, and then the wire clamp pulls it off. This prevents the metal wire from "flying" directly through the 50mm hole of the cutter, and the upward pulling action of the wire clamp straightens the metal wire, ensuring the straightness of the vertical line welding.

[0064] In the control method, step S1 initially positions the wire cutter assembly 70 above the tip of the wedge 50. Combined with the structural design of the device in which the wire cutter and the ignition needle 60 are respectively located on both sides of the welding wire 2, it ensures that there is no spatial interference between the ignition needle 60 and the wire cutter during the ball-burning stage. In step S2, the bonding head base 20 drives the wedge 50 to move down to complete one weld. Relying on the structural characteristics of the constant bonding force output by the flat four-module in the device, and in conjunction with the energy output of the ultrasonic transducer 30, it ensures the stable transmission of welding point pressure and ultrasonic energy, laying a precise foundation for subsequent vertical wire welding.

[0065] Step S3 involves vertically raising the bonding head base 20 to "release the vertical wire of the preset length 2". Relying on the precision guidance of the Z-axis moving mechanism in the device and the wire length control structure of the cutting blade 50, the error of the reserved wire length is minimized each time. Combined with the three-way adjustment structure of the wire cutter assembly 70 (the distance between the left and right sides is 1 / 3 to 1 / 2 of the wire diameter), the wire cutting position is made to correspond precisely with the preset wire length, avoiding abnormal wire cutting depth or position due to wire length deviation.

[0066] The reset step relies on the reset spring structure of the wire cutter flat four-component 72, which can realize the automatic return of the wire cutter without additional power, reduce the complexity of control logic, reduce timing disorder caused by power component failure, and ensure the consistency of welding parameters of each welding wire 2 in mass production.

[0067] The control method replaces the complex wire breakage logic of arc initiation, bending, and secondary damage in related technologies by using wire pre-processing and gentle pulling of wire clamps. Combined with the integrated structure of the wire cutter and bonding head base 20 in the device, it eliminates the need for independent drive coordination and the design of no additional air or circuit circuits, where reset and shearing force both rely on springs. This greatly simplifies the control difficulty and structural complexity of the equipment, reduces failure points, and improves the stability of long-term operation.

[0068] The basic principles, main features, and advantages of this application have been described above. Those skilled in the art should understand that this application is not limited to the above embodiments. The embodiments and descriptions in the specification are merely the principles of this application. Various changes and modifications can be made to this application without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection claimed by this application is defined by the appended claims and their equivalents.

Claims

1. A ball-bonding wire bonding device, characterized in that, include: A vertical base and a bonding head base, wherein the bonding head base is connected to the vertical base and the bonding head base is movable vertically relative to the vertical base; An ultrasonic transducer and a wire clamp assembly are indirectly mounted on a bonding head base. A cutting tool is connected to the ultrasonic transducer, and a welding wire is held by the wire clamp assembly and passes through the cutting tool. The ignition needle is connected to the vertical base and is used in conjunction with the cleaver to complete the welding wire burning process, that is, to complete one welding operation. A wire cutter assembly, connected to the bonding head base, is used to cut the welding wire; The wire cutter assembly includes a wire cutting adjustment assembly, a wire cutting flat assembly, and a wire cutting opening and closing assembly. One end of the wire cutting adjustment assembly is connected to the bonding head base, and the other end is connected to the wire cutting flat assembly. One end of the wire cutting opening and closing component is connected to the wire cutting flat component, and the other end is used to cut the welding wire; The wire cutting adjustment component is used to drive the wire cutting flat component to adjust its position. The wire cutting flat component is used to drive the wire cutting opening and closing component to move closer to or away from the welding wire.

2. The ball bonding wire bonding apparatus as described in claim 1, characterized in that, The wire-cutting adjustment assembly includes an upper and lower adjustment seat. The upper and lower adjustment seat includes a first connecting end parallel to the bonding head base. The first connecting end has an upper and lower adjustment hole extending in the upper and lower direction. The upper and lower adjustment seat is connected to the bonding head base by an upper and lower adjustment seat locking pin passing through the upper and lower adjustment hole. Adjusting the position of the upper and lower adjustment seat locking pin within the upper and lower adjustment hole adjusts the position of the upper and lower adjustment seat relative to the bonding head base in the upper and lower direction.

3. The ball bonding wire bonding apparatus as described in claim 2, characterized in that, The up-down adjustment seat also includes a second connecting end for connecting to the wire-cutting flat four-piece assembly. The second connecting end is inclined relative to the first connecting end, and the wire-cutting flat four-piece assembly can move left and right relative to the second connecting end. The wire-cutting adjustment assembly further includes a left-right adjustment seat, which includes a left-right adjustment knob, a knob buckle, and a knob locking pin. The knob locking pin passes through the knob buckle and connects to the side wall of the second connecting end. The left-right adjustment knob passes through the knob buckle and connects to the wire-cutting flat assembly. By rotating the left-right adjustment knob, the left-right movement adjustment of the wire-cutting flat assembly relative to the upper and lower adjustment seat can be achieved.

4. The ball bonding wire bonding apparatus as described in claim 3, characterized in that, The wire-cutting flat four-piece assembly includes: The wire-cutting flat four-sided fixed end is used to connect with the second connecting end of the upper and lower adjusting seat; The wire-cutting flat four-sided movable end is used to connect with the wire-cutting opening and closing assembly; The flat four-piece connecting plate and multiple sets of spring plates are provided. The flat four-piece connecting plate is connected to the fixed end of the wire shearing flat four-piece through one set of spring plates, and the flat four-piece connecting plate is connected to the movable end of the wire shearing flat four-piece through another set of spring plates. A driving component is sandwiched between the fixed end of the wire shearing flat four and the movable end of the wire shearing flat four, and is drivingly connected to the movable end of the wire shearing flat four; The drive assembly drives the movable end of the wire shearing flat wire to move, and multiple sets of spring plates deform to complete the movement of the movable end of the wire shearing flat wire towards or away from the welding wire.

5. The ball bonding wire bonding apparatus as described in claim 4, characterized in that, The wire-cutting flat four-piece assembly also includes a reset component, one end of which is connected to the movable end of the wire-cutting flat four-piece assembly, and the other end of which is connected to the drive component; When the driving component removes the driving force, the reset component drives the movable end of the wire shearing flat four to reset.

6. The ball bonding wire bonding apparatus as described in claim 4, characterized in that, The wire-cutting opening and closing assembly includes: A ceramic plate holder, one end of which is connected to the movable end of the shear line flat four-sided structure; A piezoelectric ceramic sheet is connected to the main body of the ceramic sheet holder. A wire-cutting stationary arm, which is connected to the ceramic plate holder. A wire-cutting boom, wherein the wire-cutting boom is connected to the wire-cutting stationary boom via a switch top post, and the switch top post abuts against the piezoelectric ceramic plate; An elastic element, one end of which is connected to the stationary shear arm and the other end of which is connected to the movable shear arm; Specifically, the piezoelectric ceramic sheet deforms at its end to open the switch top post, which in turn drives the wire-cutting arm away from the wire-cutting stationary arm. When the wire-cutting opening and closing assembly moves down to the lower end of the blade tip, the piezoelectric ceramic sheet closes, and the wire-cutting arm rebounds through the elastic element to approach the wire-cutting stationary arm to complete the wire-cutting action.

7. The ball bonding wire bonding apparatus as described in claim 6, characterized in that, The distance between the wire shearing arm and the welding wire is set to be between 1 / 3 and 1 / 2 of the welding wire diameter.

8. A control method for a ball-bonding wire bonding device, characterized in that, The control method for the ball bonding wire bonding apparatus is applicable to the ball bonding wire bonding apparatus as described in any one of claims 1-7, and the control method includes: Step S1: Control the wire cutter assembly to move to a position above the tip of the cleaver. The cleaver guides the welding wire and works with the ignition needle to complete the ball-burning operation. Step S2: The bonding head base moves the wedge vertically downwards to press the weld wire after the ball is heated onto the lower welding pad. At the same time, the ultrasonic transducer outputs ultrasonic energy to complete the welding. Step S3: After the welding of the wire end is completed, the bonding head base rises vertically and the welding wire of the preset length is released through the cleaver. Step S4: Drive the wire cutter assembly to cut the welding wire at a preset length position on the upright wire; Step S5: After the wire breaks, the wire clamp assembly opens, the bonding head base is reset as a whole, completing the wire cutting process for a single vertical wire welding operation, and preparing for the next cycle.

9. The control method for the ball bonding wire bonding apparatus as described in claim 8, characterized in that, Step S4 also includes step S41: after welding is completed and the height of the welding wire is reserved, the wire cutter assembly cuts the welding wire to form a cutting depth of 80%-90% of the welding wire diameter; Step S42: The wire clamp assembly closes and clamps the welding wire so that it moves vertically upward along the bond head base, and the welding wire is broken by using the weak point formed by the wire cut.

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