Ball bonding wire bonding device and control method thereof

Abstract

The invention discloses a ball bonding wire bonding device and a control method thereof, the ball bonding wire bonding device comprises a vertical base and a bonding head base, the bonding head base is connected with the vertical base, and the bonding head base can move along the vertical direction 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; the chopper is connected with the ultrasonic transducer, and the welding wire is clamped by the wire clamp assembly and penetrates out of the chopper; the ignition needle is connected with the vertical base, and the ignition needle is used for being matched with the chopper to complete welding wire ball burning, namely primary welding is completed; the wire cutter assembly is connected with the bonding head base, the wire cutter assembly and the ignition needle are located on the two sides of the welding wire, and after primary welding is completed, the bonding head base vertically moves upwards, a proper amount of the welding wire is released from the chopper, and then the wire cutter assembly cuts the welding wire immediately.

Description

Technical Field

[0001] The present application relates to the field of semiconductor back-end packaging, and more particularly to a ball-wire bonding device and a control method thereof. Background Art

[0002] Wire bonding equipment is a key equipment in the field of semiconductor back-end packaging. The core principle of its bonding is to use a terminal splitter to weld the metal wire between the chip pad and the substrate pad under the conditions of heating, constant pressure, and ultrasonic output to achieve electrical interconnection between the two. Therefore, the bonding in related technologies mainly includes five actions: first welding, arcing, second welding, tail retention, and wire breaking.

[0003] In the more advanced packaging field, there is an application scenario for the flip-chip process, which is to connect the pads of the upper and lower layers. This is usually done using a "stacked ball" or "upright wire" welding process. The stacked ball process simply relies on burning balls and then stacking them layer by layer to achieve the connection between the upper and lower pads. However, for devices with relatively large height distances, the stacked ball process is obviously no longer suitable, and the upright wire welding process is required. For upright wire, the first weld is performed, and then the wire is released by moving it vertically to a fixed length, and then a wire clamp is used to break the wire. Currently, the main method to break the upright wire is to flip the metal wire during the arc starting process to create a stress point. Then, "light welding" is performed at the stress point. The stress point is secondary damaged by applying ultrasound and pressure, and finally the wire is broken by the wire clamp. This method of breaking the wire is particularly complex in terms of arc starting logic, and the clamping force must be very strong. Otherwise, the wire clamp will easily slip, resulting in inconsistent breakpoints and uneven upright wire heights, seriously affecting the quality of the client's product. Summary of the Invention

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

[0005] To achieve the above objectives, the technical solution adopted in the present application is: to provide a ball welding wire bonding device, comprising: a vertical base, a bonding head base, the bonding head base is connected to the vertical base, and the bonding head base can move vertically relative to the vertical base; an ultrasonic transducer, a wire clamp assembly, the ultrasonic transducer and the wire clamp assembly are indirectly mounted on the bonding head base; a splitting knife, the splitting knife is connected to the ultrasonic transducer, the welding wire is clamped by the wire clamp assembly and passes through the splitting knife arrangement; a spark needle, the spark needle is connected to the vertical base, the spark needle is used to cooperate with the splitting knife to complete the welding wire burning ball, that is, to complete a welding; a wire cutter assembly, the wire cutter assembly is connected to the bonding head base, and is arranged on both sides of the welding wire with the spark needle. After a welding is completed, the bonding head base moves vertically upward, and after an appropriate amount of welding wire is released from the splitting knife, the wire cutter assembly immediately cuts the welding wire.

[0006] As a preferred embodiment, the wire cutter assembly includes a wire trimmer adjustment assembly, a wire trimmer flat four assembly and a wire trimmer opening and closing assembly, one end of the wire trimmer adjustment assembly is connected to the bonding head base, and the other end is connected to the wire trimmer flat four assembly; one end of the wire trimmer opening and closing assembly is connected to the wire trimmer flat four assembly, and the other end is used to shear the welding wire; wherein, the wire trimmer flat four assembly is driven by the wire trimmer adjustment assembly to adjust its position, and the wire trimmer flat four assembly is used to drive the wire trimmer opening and closing assembly close to or away from the welding wire.

[0007] As another preferred embodiment, the wire trimming adjustment assembly includes an upper and lower adjustment seat, and the upper and lower adjustment seat includes a first connecting end parallel to the bond head base, and the first connecting end is penetrated by an upper and lower adjustment hole extending in the upper and lower directions, and then the upper and lower adjustment seat is connected to the bond head base by passing the upper and lower adjustment seat locking pins through the upper and lower adjustment holes, and the position of the upper and lower adjustment seat locking pins in the upper and lower adjustment holes is adjusted to adjust the position of the upper and lower adjustment seat relative to the bond head base in the upper and lower directions.

[0008] Further preferably, the upper and lower adjustment seat also includes a second connecting end for connecting to the thread trimmer flat four component, the second connecting end is inclined relative to the first connecting end, and the thread trimmer flat four component can move left and right relative to the second connecting end; the thread trimmer adjustment component also includes a left and right adjustment seat, and the left and right adjustment seat includes a left and right adjustment knob, a knob buckle and a knob locking nail, the knob locking nail passes through the knob buckle and is connected to the side wall of the second connecting end, the left and right adjustment knob passes through the knob buckle and is connected to the thread trimmer flat four component, and the left and right movement adjustment of the thread trimmer flat four component relative to the upper and lower adjustment seat is achieved by rotating the left and right adjustment knob.

[0009] Further preferably, the trimmer flat quad assembly includes: a trimmer flat quad fixed end, the trimmer flat quad fixed end is used to be connected to the second connecting end of the upper and lower adjustment seats; a trimmer flat quad movable end, the trimmer flat quad movable end is used to be connected to the trimmer opening and closing assembly; a flat quad connecting plate and multiple groups of spring leaves, the flat quad connecting plate and the trimmer flat quad fixed end are connected by a group of the spring leaves, and the flat quad connecting plate and the trimmer flat quad movable end are connected by another group of the spring leaves; a driving assembly, the driving assembly is clamped between the trimmer flat quad fixed end and the trimmer flat quad movable end, and is drivingly connected to the trimmer flat quad movable end; wherein, the trimmer flat quad movable end is driven to move by the driving assembly, and multiple groups of the spring leaves are deformed to complete the movement of the trimmer flat quad movable end close to or away from the welding wire.

[0010] Further preferably, the trimmer assembly further includes a reset member, one end of which is connected to the movable end of the trimmer, and the other end is connected to the drive assembly; wherein, when the drive assembly cancels the driving force, the reset member is used to drive the movable end of the trimmer to reset.

[0011] Preferably, the wire cutting opening and closing assembly includes: a ceramic piece seat, one end of the ceramic piece seat is connected to the four movable ends of the wire cutting plane; a piezoelectric ceramic piece, the piezoelectric ceramic piece is connected to the main body of the ceramic piece seat, a wire cutting static arm, the wire cutting static arm is connected to the ceramic piece seat, a wire cutting movable arm, the wire cutting movable arm is connected to the wire cutting static arm through a switch top column, and the switch top column abuts against the piezoelectric ceramic piece; an elastic member, one end of the elastic member is connected to the wire cutting static arm, and the other end is connected to the wire cutting movable arm; wherein, the switch top column is pushed open by the deformation of the end portion of the piezoelectric ceramic piece, and then the switch top column drives the wire cutting movable arm away from the wire cutting static arm, and when the wire cutting opening and closing assembly moves down to the lower end of the blade tip of the cleaver, the piezoelectric ceramic piece is closed, and the wire cutting movable arm is reset and rebounded by the elastic member to approach the wire cutting static arm to complete the wire cutting action on the welding wire.

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

[0013] Furthermore, the present application document also provides a control method for a ball welding wire bonding device, which is applicable to a ball welding wire bonding device as described in any one of the above, and the control method includes: step S1: controlling the wire cutter assembly to move to a position above the tip of the splitting knife, and the splitting knife guides the welding wire to cooperate with the spark pin to complete the ball burning operation; step S2: the bonding head base drives the splitting knife to move vertically downward, and presses the burned welding wire onto the lower pad, while the ultrasonic transducer outputs ultrasonic energy to complete the welding; step S3: after the welding end of the welding wire is completed, the bonding head base rises vertically, and releases the welding wire of a preset length of the vertical line through the splitting knife; step S4: driving the wire cutter assembly to perform a wire cutting operation on the welding wire at the preset length position of the vertical line; step S5: after the wire is broken, the wire clamp assembly opens, and the bonding head base is reset as a whole, completing the wire cutting and wire breaking process of a single vertical line welding, and preparing for the next cycle.

[0014] Furthermore, step S4 also includes step S41: after welding is completed and the height of the vertical line of the welding wire is reserved, the wire cutter assembly shears the welding wire to form a cutting depth of 80%-90% of the wire diameter of the welding wire; step S42: the wire clamp assembly closes and clamps the welding wire to move vertically along with the bonding head base, and the welding wire is torn off by using the weak point formed by cutting the wire.

[0015] Compared with the prior art, the present invention has the following advantages: The wire cutter assembly is set up to ensure stable wire breaking when the wire bonding device is performing vertical wire welding on the wire, so as to improve welding reliability. The wire cutter assembly is connected to the base of the bonding head and can move vertically synchronously with the bonding head to ensure that during the vertical wire welding process, the wire cutting position can always maintain precise correspondence with the reserved height of the welding wire and the position of the chopping knife, avoiding wire cutting deviation caused by relative displacement and improving the continuity of wire cutting and subsequent wire breaking actions.

[0016] The wire cutter and ignition needle are separately arranged on both sides of the welding wire, which can not only allow the ignition needle to complete the ball burning operation independently without being blocked or affected by the wire cutter, but also reduce the spatial conflict between components when the wire cutter cuts the welding wire, thereby improving the stability of the device operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a structural schematic diagram of the wire cutter assembly in the ball bond wire bonding device in the wire cutting position.

[0018] Figure 2 This is a schematic diagram of the structure of the ball welding wire bonding device when the welding wire is ignited.

[0019] Figure 3 This is a structural diagram of the thread cutter adjustment component.

[0020] Figure 4It is a structural diagram of the four components of the thread cutter.

[0021] Figure 5 This is a structural diagram of the thread cutter opening and closing assembly.

[0022] Figure 6 This is a structural diagram of the blade position in the thread cutter opening and closing assembly.

[0023] Figure 7 for Figure 6 A partial enlarged view of point A in the middle.

[0024] Figure: 1. Ball solder wire bonding device; 2. Solder wire; 10. Vertical base; 20. Bond head base; 30. Ultrasonic transducer; 40. Wire clamp assembly; 50. Chopper; 60. Spark pin; 70. Wire cutter assembly; 80. Flat four module one; 71. Thread trimmer adjustment assembly; 711. Up and down adjustment seat; 712. First connection end; 713. Second connection end; 714. Up and down adjustment hole; 715. Up and down adjustment seat locking pin; 716. Left and right adjustment seat; 7161. Left and right adjustment knob; 7162. Knob buckle; 7163. Knob locking pin; 717. Left and right adjustment seat locking pin; 72. Trimming flat plate assembly; 721. Trimming flat plate fixed end; 722. Trimming flat plate movable end; 723. Flat plate connecting plate; 724. Spring plate; 725. Drive assembly; 7251. Motor stator; 7252. Motor mover; 7253. Stator locking seat 1; 7254. Stator locking seat 2; 7255. Limiting ceramic ball; 7256. Spring adjustment screw; 726. Reset element; 7271. Locking seat 1 fixing screw; 7272. Locking seat 2 fixing screw; 728. Spring plate pressure plate; 7281. Pressure plate locking nail; 729. Alloy steel limit block; 73. Thread trimmer opening and closing assembly; 731. Ceramic disc holder; 7311. Ceramic disc holder locking pin; 732. Piezoelectric ceramic disc; 733. Thread trimmer static arm; 7331. Thread trimmer static arm locking pin; 7332. Height adjustment hole; 734. Thread trimmer movable arm; 735. Elastic part; 736. Switch top column; 7361. Top column locking screw; 737. Switch fulcrum column; 738. Ceramic disc pressure plate; 739. Pressure plate locking screw; 740. Shear force adjustment nut; 741. Shear force adjustment screw; 742. Nut locking screw; 743. Blade. DETAILED DESCRIPTION

[0025] Below, the present application is further described in conjunction with specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0026] In the description of this application, it should be noted that for directional words, such as the terms "center", "horizontal", "longitudinal", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and so on, the directions and positional relationships indicated are based on the directions or positional relationships shown in the accompanying drawings, which 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, be constructed and operated in a specific orientation, and cannot be understood as limiting the specific scope of protection of this application.

[0027] It should be noted that the terms "first", "second", etc. in the description and claims of this application are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

[0028] The terms "comprises" and "having" and any variations thereof in the specification and claims of this application are intended to cover non-exclusive inclusions. For example, a process, method, system, product or apparatus that includes a series of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, product or apparatus.

[0029] In a preferred embodiment, see Figures 1 to 7 The present application document provides a ball welding 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 being 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; a splitting knife 50, the splitting knife 50 being connected to the ultrasonic transducer 30, the welding wire 2 being clamped by the wire clamp assembly 40 and passing through the splitting knife 50 0 setting; ignition needle 60, the ignition needle 60 is connected to the vertical base 10, and the ignition needle 60 is used to cooperate with the splitting knife 50 to complete the burning of the welding wire 2, that is, to complete one welding; wire cutter assembly 70, the wire cutter assembly 70 is connected to the bonding head base 20, and is arranged on both sides of the welding wire 2 with the ignition needle 60. After one welding is completed, the bonding head base 20 moves vertically upward, and after an appropriate amount of welding wire 2 is released from the splitting knife 50 and the vertical line height of the welding wire 2 is determined, the wire cutter assembly 70 immediately cuts the welding wire 2.

[0030] The vertical base 10 in this application document is specifically a Z-direction base, and the Z direction is Figure 1 and Figure 2In the vertical upward direction, the vertical base 10 is fixed, and a combination of one or more structures such as rollers and tracks can be connected between the bonding head base 20 and the vertical base 10, so that the bonding head base 20 can move up and down relative to the vertical base 10. The bonding head base 20 is extended with a longer support arm to connect a wire clamp assembly 40, which is used for the welding wire 2 to pass through and can be used to clamp the tail end position of the welding wire 2; the wire clamp assembly 40 and the ultrasonic transducer 30 are arranged at intervals, and the ultrasonic transducer 30 is connected to the bonding head base 20 through a flat four-module 80, wherein the flat four-module 80 is specifically a parallelogram structure, one end of which is fixedly mounted on the bonding head base 20, and the other end is a movable end, and the movable end is equipped with an ultrasonic transducer 30 and moves up and down together with the splitting knife 50, and can output a constant bonding force acting on the solder joint through hinge deformation and motor power compensation.

[0031] The spark pin 60 is fixed to the vertical base 10 and does not move up and down with the bond head base 20. When sparking and sintering are required before a weld, the splitter 50 first descends to a set height. The spark pin 60 discharges a high voltage to sinter the welding wire 2. The bond head base 20 and splitter 50 then descend to the welding surface, completing the weld. The wire clamp assembly 40 is fixed to the bond head base 20 and moves up and down with the bond head. Its primary function is to sever the wire after the wire cutter assembly 70 has trimmed the welding wire 2, thus completing the weld.

[0032] Specifically, the wire cutter assembly 70 is used for the wire bonding device to stably break the wire when performing vertical wire welding on the welding wire 2, so as to improve the welding reliability. The wire cutter assembly 70 is connected to the bonding head base 20 and can move vertically synchronously with the bonding head to ensure that during the vertical wire welding process, the wire cutting position can always keep precise correspondence with the reserved height of the welding wire 2 and the position of the splitter 50, avoiding the wire cutting deviation caused by relative displacement and improving the consistency of the wire cutting and subsequent wire breaking actions; the wire cutter and the ignition needle 60 are respectively arranged on both sides of the welding wire 2, which can not only allow the ignition needle 60 to complete the ball burning operation independently without being blocked or affected by the wire cutter, but also enable the wire cutter to shear the welding wire 2, reducing the space between components. The wire cutter is close to the integrated layout of the wire clamp assembly 40 and the splitting knife 50, which can shorten the action distance from wire cutting to wire clamp breaking, so that the weak point formed by wire cutting is more evenly stressed during the breaking process, effectively avoiding "flying wire" or bending of the welding wire 2, ensuring the straightness and consistency of vertical wire welding, and thus improving welding reliability. It is preferably suitable for alloy wires with a wire diameter of more than 50um; the wire cutter assembly 70 is integrated into the bonding head base 20, and no additional independent driving mechanism is required to coordinate its positional relationship with the bonding head, which reduces complex transmission components, reduces the size of the device and the risk of failure, and is convenient for synchronously controlling the action timing of the wire cutter, wire clamp and bonding head through a unified control module.

[0033] As a preferred embodiment, the wire cutter assembly 70 includes a wire cutting adjustment assembly 71, a wire cutting flat four 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 four assembly 72; one end of the wire cutting opening and closing assembly 73 is connected to the wire cutting flat four assembly 72, and the other end is used to cut the welding wire 2; wherein, the wire cutting adjustment assembly 71 is used to drive the wire cutting flat four assembly 72 to adjust its position, and the wire cutting flat four assembly 72 is used to drive the wire cutting opening and closing assembly 73 to approach or move away from the welding wire 2.

[0034] in, Figure 2 This is a schematic diagram of the structure of the ball welding wire bonding device 1 in the process of igniting the welding wire 2. When the welding wire 2 is ignited and the ball is burned, see Figure 1 The welding wire 2 is sheared by the wire cutter assembly 70.

[0035] As another preferred option, see Figure 3The wire trimming adjustment assembly 71 includes an upper and lower adjustment seat 711, and the upper and lower adjustment seat 711 includes a first connection end 712 parallel to the bond head base 20. The first connection end 712 is penetrated by an upper and lower adjustment hole 714 extending in the up and down direction. Then, the upper and lower adjustment seat 711 passes through the upper and lower adjustment hole 714 through the upper and lower adjustment seat locking pin 715 to be connected to the bond head base 20. 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 bond head base 20 in the up and down direction.

[0036] Further preferably, the upper and lower adjustment seat 711 further includes a second connection end 713 for connecting to the trimmer flat four component 72, the second connection end 713 is tilted relative to the first connection end 712, and the trimmer flat four component 72 can move left and right relative to the second connection end 713; the trimmer adjustment component 71 further includes a left and right adjustment seat 716, the left and right adjustment seat 716 includes a left and right adjustment knob 7161, a knob buckle 7162 and a knob locking nail 7163, the knob locking nail 7163 passes through the knob buckle 71 62 is connected to the side wall of the second connecting end 713, and the left and right adjustment knobs 7161 are connected to the trimmer flat four components 72 through the knob buckle 7162. The left and right adjustment knobs 7161 are rotated to realize the left and right movement adjustment of the trimmer flat four components 72 relative to the upper and lower adjustment seats 711. When the trimmer flat four components 72 are adjusted to the appropriate position by the left and right adjustment knobs 7161, the left and right adjustment seat locking pins 717 cooperate with the second connecting end 713 to lock and fix the left and right adjustment knobs 7161.

[0037] Specifically, the upper and lower adjustment seats 711 are used to control the overall large-scale up and down movement adjustment of the wire cutter assembly 70. Similarly, the left and right movement of the wire trimmer flat assembly 72 relative to the upper and lower adjustment seats 711 is also used to control the overall large-scale left and right movement adjustment of the wire cutter assembly 70; the upper and lower adjustment holes 714 are specifically a through hole with a long strip opening shape, and the upper and lower adjustment seats 711 are fixedly connected to the bond head base 20 through the upper and lower adjustment seat locking pins 715. The upper and lower adjustment seat locking pins 715 are located at different positions in the upper and lower adjustment holes 714, thereby adjusting the upper and lower adjustment seats 711 to different height positions relative to the bond head base 20 in the upper and lower directions.

[0038] See also Figure 3 and Figure 4, since the second connection end 713 corresponds to the connection with the trimmer leveler assembly 72, and the trimmer leveler assembly 72 includes the trimmer leveler fixed end 721 and the trimmer leveler movable end 722, the second connection end 713 in the upper and lower adjustment seat 711 is specifically connected to the trimmer leveler fixed end 721, and a trapezoidal groove is provided at the second connection end 713 of the upper and lower adjustment seat 711, corresponding to the trapezoidal protrusion on the trimmer leveler fixed end 721, wherein the trapezoidal groove of the second connection end 713 extends along the left and right directions, and then when the trapezoidal protrusion in the trimmer leveler fixed end 721 is embedded in the trapezoidal groove of the second connection end 713, the trimmer leveler fixed end 721 can move along the left and right directions relative to the upper and lower adjustment seat 711.

[0039] When the locksmith tool 71 is unlocked, the the locksmith tool 71 is unlocked, and the locksmith tool 71 is unlocked, so that the locksmith tool 71 is unlocked.

[0040] For further optimization, see Figure 4 When the handle 721 is in the closed position, the second end 722 of the lifting arm 710 is tightened, and the second end 722 of the lifting arm 710 is tightened. When the handle 721 is in the closed position, the second end 722 of the lifting arm 710 is tightened, and the second end 722 of the lifting arm 710 is tightened. When the handle 721 is in the closed position, the second end 722 of the lifting arm 710 is tightened, and the second end 722 of the lifting arm 710 is tightened.

[0041] Specifically, multiple groups of spring leaves 724 and flat four connecting plates 723 are connected on both sides of the trimmer flat four fixed end 721 and the trimmer flat four movable end 722, among which the spring leaves 724 are preferably provided with four groups, four groups of spring leaves 724 with high fatigue strength to achieve the purpose of long service life; a flat four connecting plate 723 and two groups of spring leaves 724 are provided on one side of the trimmer flat four fixed end 721 and the trimmer flat four movable end 722, and a spring leaf pressure plate 728 is also provided on the top of the spring leaf 724, and then the pressure plate locking nail 7281 is used to realize the connection between the spring leaf pressure plate 728 and the spring leaf 724 and the trimmer flat four fixed end 721, the flat four connecting plate 723 and the trimmer flat four movable end 722. Therefore, by the arrangement of the spring pieces 724 and the flat four connecting plates 723 on both sides of the trimmer flat four fixed end 721 and the trimmer flat four movable end 722, the trimmer flat four movable end 722 can be adjusted and moved relative to the trimmer flat four fixed end 721 in a similar parallelogram structure, such as Figure 1 and Figure 2 The structure of the middle shear line flat four components 72 has been changed.

[0042] Among them, driving the trimmer level four movable end 722 is achieved through the driving component 725, and the driving component 725 specifically includes a motor stator 7251 and a motor mover 7252. The outside of the motor stator 7251 is covered with a stator locking seat 1 7253 and a stator locking seat 2 7254. The stator locking seat 1 7253 is fixedly connected to the trimmer level four fixed end 721 through a locking seat 1 fixing screw 7271, and the stator locking seat 2 7254 is fixedly connected to the stator locking seat 1 7253 through a locking seat 2 fixing screw 7272, so that 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 trimmer level four movable end 722, and the trimmer level four movable end 722 is driven to move by the motor mover 7252.

[0043] More preferably, the trimmer assembly 72 further includes a reset member 726, one end of which is connected to the trimmer movable end 722, and the other end is connected to the drive assembly 725; wherein, when the drive assembly 725 withdraws the driving force, the trimmer movable end 722 is driven to reset by the reset member 726. The reset member 726 is specifically a reset spring, which drives the trimmer movable end 722 in the shearing position back to its original position through its telescopic reset action, see Figure 4 One end of the reset spring is connected to the movable end 722 of the trimmer level four, and the other end is connected to the spring adjustment screw 7256 provided on the locking seat two. The spring adjustment screw 7256 can be rotated to adjust the height position of the screw relative to the locking seat two, thereby determining the position of the movable end 722 of the trimmer level four after the reset spring is reset.

[0044] Limiting ceramic balls 7255 are also provided on both sides of the stator locking seat 7254, and alloy steel limiting blocks 729 are also provided on both sides of the limiting ceramic balls 7255 corresponding to the movable end 722 of the wire trimmer. When the movable end 722 of the wire trimmer moves driven by the driving assembly 725, the alloy steel limiting block 729 moves synchronously with the movable end until it contacts 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 accurately controlling the maximum displacement of the movable end 722 of the wire trimmer, thereby avoiding collision or interference between the wire cutter assembly 70 and other components, such as the chopper 50 and the welding wire 2, due to excessive driving. Therefore, the repeatability of the upper and lower movements of the thread cutter is guaranteed by the two sets of hard limits set above. The upper and lower limits are both point contacts. During the installation process, this structure can reduce the parallelism requirements of the movable end of the parallel rod relative to the fixed end, 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 considerations of the long service life of the thread cutter mechanism.

[0045] At the same time, the limiting ceramic ball 7255 and the alloy steel limiting block 729 are used to determine the fixed limiting point to ensure that the four movable ends 722 of the wire trimmer can reach the same limit position each time they move, so that the cutting position, angle and other parameters of the wire trimmer assembly 70 remain stable, avoiding the influence of stroke deviation on the wire trimming depth and accuracy, thereby ensuring the consistency of vertical line welding.

[0046] Furthermore, the inclination angle of the wire cutting plane component 72 in the wire cutting component 70 is the angle between the up and down movement direction of the wire cutting component 70 and the horizontal plane. The selection of this angle takes into account the avoidance of the wire cutting device in the welding area, and also takes into account the welding of devices with a certain cavity depth requirement. Therefore, the preferred inclination angle of this application document is set at 45-60 degrees.

[0047] Preferably, see Figure 5The trimmer opening and closing assembly 73 includes: a ceramic piece seat 731, one end of which is connected to the trimmer flat four movable end 722; a piezoelectric ceramic piece 732, which is connected to the main part of the ceramic piece seat 731; a trimmer static arm 733, which is connected to the ceramic piece seat 731; a trimmer movable arm 734, which is connected to the trimmer static arm 733 through a switch top column 736, and the switch top column 736 abuts against the piezoelectric ceramic piece 732; an elastic member 735, One end of the elastic member 735 is connected to the fixed wire trimming arm 733, and the other end is connected to the movable wire trimming arm 734; wherein, the end of the piezoelectric ceramic piece 732 is deformed to push open the switch top column 736, and then the switch top column 736 drives the movable wire trimming arm 734 away from the fixed wire trimming arm 733. When the wire trimming opening and closing assembly 73 moves down to the lower end of the blade tip of the splitting knife 50, the piezoelectric ceramic piece 732 is closed, and the movable wire trimming arm 734 is reset and rebounded by the elastic member 735 to approach the fixed wire trimming arm 733 to complete the wire trimming action of the welding wire 2.

[0048] Specifically, a slot is provided on the ceramic disc seat 731 for the piezoelectric ceramic disc 732 to be embedded, and a ceramic disc pressure plate 738 is provided on the end of the piezoelectric ceramic disc 732 away from the trimmer static arm 733 for fixing and limiting. The ceramic disc pressure plate 738 is fixedly connected to the ceramic disc seat 731 through a pressure plate locking screw 739. At the same time, the ceramic disc seat 731 is fixedly connected to the trimmer flat four movable end 722 through a ceramic disc seat locking pin 7311, so that the ceramic disc seat 731 is fixedly connected to the trimmer flat four movable end 722 is fixedly arranged, and a height adjustment hole 7332 is provided on the trimmer static arm 733. The height adjustment hole 7332 has a certain adjustment stroke, and then the trimmer static arm 733 passes through the height adjustment hole 7332 through the trimmer static arm locking pin 7331 to be fixed on the ceramic plate seat 731, and the position of the trimmer static arm 733 can be adjusted within a small range by adjusting the position of the trimmer static arm locking pin 7331 relative to the height adjustment hole 7332. The adjustment position needs to ensure that the trimmer static arm 73 3 extends out of the ceramic sheet seat 731 to prevent the ceramic sheet seat 731 from interfering with the shearing; a switch fulcrum column 737 is also protruded on the static arm 733 of the trimmer, and the switch fulcrum column 737 is a pin with two heads with a certain taper. The movable arm 734 of the trimmer is positioned by the switch fulcrum column 737, so as to be aligned with the static arm 733 of the trimmer. Due to the setting of the switch fulcrum column 737, the movable arm 734 of the trimmer can open a certain gap relative to the static arm 733 of the trimmer; the switch top column 736 is inserted through The thread trimming movable arm 734 and the thread trimming static arm 733 are against the piezoelectric ceramic piece 732, and the switch top column 736 is fixedly matched with the thread trimming movable arm 734 through the top column locking top screw 7361. Then, when the switch top column 736 is pushed open by the piezoelectric ceramic piece 732 through the deformation of the end, it can drive the thread trimming movable arm 734 to move with the movement of the switch top column 736; wherein, the shearing action of the shear assembly is completed by the switch top column 736 moving away from and close to the thread trimming static arm 733.

[0049] The elastic member 735 is specifically a compression spring, and the two ends of the compression spring are respectively connected to the trimming static arm 733 and the trimming movable arm 734. When the switch top column 736 drives the trimming movable arm 734 to move away from the trimming static arm 733, the compression spring is stretched to accumulate elastic potential energy. When the piezoelectric ceramic piece 732 is closed and the pushing force on the switch top column 736 is removed, the trimming movable arm 734 can move closer to the trimming static arm 733 as the compression spring is reset to complete the shearing action.

[0050] A shear force adjustment screw 741 is also provided in the compression spring. The shear force of the wire cutter assembly 70 can be set by changing the spring force applied to the wire cutting movable arm 734. For metal wires of different materials and wire diameters, the shear force parameters used are different and need to be distinguished; specifically, the end of the shear force adjustment screw 741 has a section of thread, which is screwed onto the wire cutting static arm 733. The movable arm and the static arm can be connected and fitted together by locking the two switch fulcrum columns 737 and the shear force adjustment screw 741. The other end of the shear force adjusting screw 741 is provided with a shear force adjusting nut 740, and the shear force adjusting nut 740 and the compression spring are fixed 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 can be determined. The shorter the distance between the shear force adjusting nut 740 and the trimming static arm 733, the greater the elastic potential energy accumulated after the compression spring is deformed, and the stronger the shear force generated by the trimming movable arm 734 after rebound reset, and vice versa.

[0051] Therefore, in the process of adjusting a specific shear force, first loosen the nut 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 nut 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 wire diameters.

[0052] See also Figure 2 The normal position of the wire cutting end of the wire cutter assembly 70 is above the tip of the wrecking knife 50 and maintains a certain distance from the wrecking knife 50. Only when wire cutting is required, it will be sent to the bottom of the tip of the wrecking knife 50 through the up and down displacement mechanism, that is, the wire cutting flat four assembly 72. After the wire cutting is completed, it is immediately reset by the elastic member 735 in the wire cutting flat four assembly 72. 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 takes into account the feasibility of the bonding head for welding devices with a certain cavity depth.

[0053] Preferably, by adjusting the wire trimmer adjustment component 71 in conjunction with the wire trimmer flat four component 72, the wire trimmer component 70 can be adjusted in three degrees of freedom: up and down, front and back, and left and right. Among them, the left and right adjustment is particularly important for the wire trimmer. If the wire trimmer static arm 733 is far away from the welding wire 2, the wire trimmer movable arm 734 will "bend" the vertical welding wire 2 when closing, affecting the overall welding straightness; but if the distance between the two is a negative value, when the wire trimmer component 70 moves downward, it will hit the welding wire 2 to be cut, affecting the normal progress of welding. Therefore, preferably, the distance between the wire trimmer static arm 733 and the welding wire 2 is set to between 1 / 3 and 1 / 2 of the wire diameter of the welding wire 2.

[0054] For further information, see Figure 6 and Figure 7 A blade 743 is provided on the trimming arm 734. The blade 743 in this application document preferably adopts a single blade 743 structure. Therefore, in this application document, the side of the trimming static arm 733 close to the trimming arm 734 is flat, while the trimming arm 734 is a sharp blade 743; in addition, the cutting end point of the blade 743 on the trimming arm 734 is the lowest point of the arm, and 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, thereby affecting the straightness after welding.

[0055] Therefore, the ball welding lead bonding device 1 in the present application document is provided with a wire cutter assembly 70, which optimizes the vertical wire welding to a great extent. It not only solves the instability of currently relying solely on bending stress points and large-load clamping of the wire to break the wire, but also simplifies the arc-traveling logic during vertical wire welding; through the wire cutting action, the wire clamp can easily tear off the welding wire 2, and at the same time greatly improves the consistency of the vertical wire welding arc and wire height, which is crucial to improving the quality of client products.

[0056] At the same time, the wire cutter assembly 70 provided in the present application document has a simple structure and low manufacturing cost, so the original ball welding bonding machine can be upgraded to a device for vertical wire welding without adding too much extra cost; and the reset action and shear force application of the wire cutter assembly 70 are both achieved by relying on a spring, without the need for additional power or additional air circuits, which also reduces the failure rate to a certain extent and ensures the stable progress of wire bonding.

[0057] Furthermore, the present application document also provides a control method for a ball welding wire bonding device 1, which is applicable to any one of the ball welding wire bonding devices 1 described above, and the control method comprises: step S1: controlling the wire cutter assembly 70 to move to a position above the tip of the splitting knife 50, and the splitting knife 50 guides the welding wire 2 to cooperate with the ignition needle 60 to complete the ball burning operation; step S2: the bonding head base 20 drives the splitting knife 50 to move vertically downward, and presses the burned welding wire 2 onto the lower layer welding wire. On the disk, the ultrasonic transducer 30 outputs ultrasonic energy to complete the welding; step S3: after the end of the welding wire 2 is welded, the bonding head base 20 rises vertically, and the welding wire 2 of the preset length of the vertical line is released through the splitting knife 50; step S4: driving 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 broken, the wire clamp assembly 40 opens, and the bonding head base 20 is reset as a whole, completing the wire cutting and breaking process of a single vertical line welding, and preparing for the next cycle.

[0058] Furthermore, step S4 also includes step S41: after welding is completed and the vertical line height of the welding wire 2 is reserved, the wire cutter assembly 70 shears the welding wire 2 to form a cutting depth of 80%-90% of the wire diameter of the welding wire 2; step S42: the wire clamp assembly 40 closes and clamps the welding wire 2 to move vertically along with the bonding head base 20, and uses the weak point formed by cutting the wire to tear the welding wire 2 apart.

[0059] Specifically, under normal circumstances, once welding is complete and the vertical line height is reserved, the wire cutter does not completely cut the wire. Instead, it cuts 80-90% of the wire diameter before the wire clamp breaks it. This prevents the wire from "flying" directly from the 50-hole of the splitter, and the upward pulling action of the wire clamp straightens the wire, ensuring the straightness of the vertical line welding.

[0060] Among them, step S1 in the control method initially positions the wire cutter assembly 70 "above the tip of the splitting knife 50", combined with the structural design of the wire cutter and the ignition needle 60 in the device being arranged on both sides of the welding wire 2, to ensure 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 splitting knife 50 to move downward to complete a weld, relying on the structural characteristics of the flat four modules in the device to output a constant bonding force, combined with the energy output of the ultrasonic transducer 30, to ensure the stable transmission of welding point pressure and ultrasonic energy, laying a precise foundation for subsequent vertical wire welding.

[0061] In step S3, the bonding head base 20 is vertically raised to "release the vertical wire 2 of preset length". Relying on the precise guidance of the Z-axis moving mechanism in the device and the wire length control structure of the splitting knife 50, the error of the reserved wire length each time is ensured to be extremely small. Combined with the three-way adjustment structure of the wire cutter assembly 70 (the left and right distance is 1 / 3-1 / 2 of the wire diameter), the wire cutting position is accurately matched to the preset wire length, avoiding abnormal wire cutting depth or position due to wire length deviation.

[0062] The reset step relies on the reset spring structure of the trimmer flat four-component 72, which can realize the automatic return of the trimmer without additional power, reducing the complexity of the control logic, reducing the timing disorder caused by power component failure, and ensuring the consistency of the welding parameters of each welding wire 2 in batch production.

[0063] The control method uses wire cutting pre-processing and light pulling of the wire clamp to replace the complex wire breaking logic of arcing, folding and secondary damage in related technologies. Combined with the integrated structure of the wire cutter and the bonding head base 20 in the device, there is no need for independent drive to coordinate the position, and the reset and shearing force all rely on the spring without additional air path and circuit design, which greatly simplifies the difficulty of equipment control and structural complexity, reduces failure points, and improves the stability of long-term operation.

[0064] The above describes the basic principles, main features, and advantages of the present application. Those skilled in the art should understand that the present application is not limited to the above-described embodiments. The above-described embodiments and the specification merely illustrate the principles of the present application. Various changes and improvements may be made to the present application without departing from the spirit and scope of the present application. These changes and improvements fall within the scope of the present application for which protection is sought. The scope of protection claimed by the present application is defined by the appended claims and their equivalents.

Claims

1. A ball-wire bonding device, characterized in that: include: A vertical base and a bond head base, wherein the bond head base is connected to the vertical base and can move vertically 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 a bonding head base; A splitting knife, the splitting knife is connected to the ultrasonic transducer, and the welding wire is clamped by the wire clamp assembly and passes through the splitting knife; A spark pin, connected to the vertical base, and used to cooperate with the splitter to complete the burning of the welding wire, that is, to complete a weld; A wire cutter assembly is connected to the bonding head base and is used to cut the welding wire.

2. The ball-bonding wire bonding device according to claim 1, wherein: The wire trimmer assembly includes a wire trimming adjustment assembly, a wire trimming flat assembly, and a wire trimming opening and closing assembly. One end of the wire trimming adjustment assembly is connected to the bonding head base, and the other end is connected to the wire trimming flat assembly. One end of the wire trimming opening and closing assembly is connected to the wire trimming flat four-axis assembly, and the other end is used for shearing the welding wire; The trimmer adjustment assembly drives the trimmer flat four assembly to adjust its position, and the trimmer flat four assembly is used to drive the trimmer opening and closing assembly to move closer to or away from the welding wire.

3. The ball-bonding wire bonding device according to claim 2, wherein: The wire trimmer adjustment assembly includes an upper and lower adjustment seat, and the upper and lower adjustment seat includes a first connecting end parallel to the bond head base, and the first connecting end is penetrated by an upper and lower adjustment hole extending in the upper and lower directions, and then the upper and lower adjustment seat passes through the upper and lower adjustment holes through the upper and lower adjustment seat locking pins to be connected to the bond head base, and the position of the upper and lower adjustment seat locking pins in the upper and lower adjustment holes is adjusted to adjust the position of the upper and lower adjustment seat relative to the bond head base in the upper and lower directions.

4. The ball-bonding wire bonding device according to claim 3, wherein: The vertical adjustment seat further includes a second connection end for connecting to the trimming flat four-axis component, the second connection end is tilted relative to the first connection end, and the trimming flat four-axis component can move left and right relative to the second connection end; The thread trimmer adjustment assembly also includes a left and right adjustment seat, which includes a left and right adjustment knob, a knob buckle and a knob locking nail. The knob locking nail passes through the knob buckle and is connected to the side wall of the second connecting end. The left and right adjustment knob passes through the knob buckle and is connected to the thread trimmer horizontal four assembly. By rotating the left and right adjustment knob, the thread trimmer horizontal four assembly can be moved left and right relative to the upper and lower adjustment seats.

5. The ball-bonding wire bonding device according to claim 4, wherein: The trimming and leveling components include: A trimmer flat four fixed end, the trimmer flat four fixed end being used to connect with the second connecting end of the upper and lower adjustment seat; A four-way movable end for trimming the thread, the four-way movable end for trimming the thread is used to connect with the trimming opening and closing assembly; A flat-four connecting plate and multiple sets of spring leaves, wherein the flat-four connecting plate is connected to the fixed end of the trimmer flat-four via one set of the spring leaves, and the flat-four connecting plate is connected to the movable end of the trimmer flat-four via another set of the spring leaves; A driving assembly, the driving assembly being sandwiched between the fixed end of the trimmer and the movable end of the trimmer, and being drivingly connected to the movable end of the trimmer; The driving assembly drives the four movable ends of the wire trimmer to move, and the multiple groups of spring sheets are deformed to complete the movement of the four movable ends of the wire trimmer toward or away from the welding wire.

6. The ball-bonding wire bonding device according to claim 5, wherein: The trimmer assembly further includes a reset element, one end of which is connected to the movable end of the trimmer assembly, and the other end of which is connected to the drive assembly; When the driving component cancels the driving force, the reset member drives the four movable ends of the thread trimmer to reset.

7. The ball-bonding wire bonding device according to claim 5, wherein: The thread trimming opening and closing assembly comprises: A ceramic disc holder, one end of which is connected to the movable end of the trimmer; A piezoelectric ceramic sheet connected to the main body of the ceramic sheet holder. A static trimmer arm, the static trimmer arm being connected to the ceramic sheet holder, A thread trimming movable arm, the thread trimming movable arm is connected to the thread trimming static arm via a switch top post, and the switch top post abuts against the piezoelectric ceramic sheet; an elastic member, one end of which is connected to the thread trimming static arm, and the other end of which is connected to the thread trimming movable arm; The switch top column is pushed open by the deformation of the end of the piezoelectric ceramic sheet, and then the switch top column drives the wire trimming movable arm away from the wire trimming static arm. When the wire trimming opening and closing assembly moves down to the lower end of the blade tip of the wrecking knife, the piezoelectric ceramic sheet is closed, and the wire trimming movable arm is reset and rebounded by the elastic member to approach the wire trimming static arm to complete the wire trimming action of the welding wire.

8. The ball-bonding wire bonding device according to claim 7, wherein: The distance between the wire trimmer static arm and the welding wire is set to be between 1 / 3 and 1 / 2 of the welding wire diameter.

9. A control method for a ball-bonding wire bonding device, characterized in that: The control method of the ball-bonding wire bonding device is applicable to the ball-bonding wire bonding device according to any one of claims 1 to 8, and the control method includes: Step S1: Control the wire cutter assembly to move to a position above the tip of the splitter, and the splitter guides the welding wire to cooperate with the spark pin to complete the ball burning operation; Step S2: The bonding head base drives the splitter to move vertically downward, press-bonding the balled wire onto the lower pad, and simultaneously the ultrasonic transducer outputs ultrasonic energy to complete the welding. Step S3: After the welding of the wire ends is completed, the bonding head base rises vertically, and the welding wire of a preset length is released from the vertical line through the splitter; Step S4: driving the wire cutter assembly to cut the welding wire at a preset length position of the vertical line; Step S5: After the wire is broken, the wire clamp assembly opens and the bonding head base is reset as a whole, completing the wire cutting and breaking process of a single vertical wire welding cycle and preparing for the next cycle.

10. The control method of the ball-bonding wire bonding device according to claim 9, wherein: Step S4 also includes step S41: after welding is completed and the height of the welding wire vertical line 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 is closed to clamp the welding wire so that it moves vertically along with the bonding head base, and the welding wire is torn off by utilizing the weak point formed by the wire cutting.

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