A method and system for forming a vertical line arc in three-dimensional space for a wire bonding machine

Abstract

The application discloses a wire bonding machine three-dimensional space vertical line arc forming method and system, relates to the technical field of semiconductor packaging, and the method comprises the following steps: moving a cleaver to a sparking height to perform sparking and ball burning, opening a wire clamp after completing first solder joint welding, lifting the cleaver to a preset vertical line arc required length, closing the wire clamp, moving to a preset gap preparation position outside a bonding pad, controlling the cleaver tip to press down the wire to form a gap, adopting a dynamic multi-axis trajectory planning algorithm, controlling the cleaver to return to the first solder joint directly above along an optimized trajectory and reserving a wire tail height, closing the wire clamp and controlling the cleaver to be oriented and lifted along the Z axis to make the wire stretch and break at the gap, and forming a three-dimensional space vertical line arc with a vertical starting section and a preset wire tail height at the end. The method does not need to introduce any external hardware module, cooperatively controls the mechanical action of the cleaver and the multi-axis motion trajectory, and realizes the forming of the three-dimensional space high-reliability line arc in the existing equipment framework.

Description

Technical Field

[0001] This application relates to the field of semiconductor packaging technology, specifically to a method and system for forming a three-dimensional vertical arc wire in a wire bonding machine, which is applicable to wire bonding processes in advanced packaging scenarios such as three-dimensional stacked packaging, heterogeneous integration, and through-silicon via-assisted interconnection. Background Technology

[0002] Wire bonding machines, as high-end semiconductor packaging equipment integrating cutting-edge technologies from multiple disciplines such as precision mechanics, servo control, machine vision, and ultrasonic energy, have formed a mature application system in traditional two-dimensional planar packaging processes. However, with the continuous miniaturization of chip feature sizes, the number of interconnects that two-dimensional planar bonding can support is approaching theoretical saturation due to the limitations of wiring density within a physical plane. To overcome this bottleneck, semiconductor packaging technology is evolving towards a three-dimensional stacked architecture to achieve higher functional density and performance integration.

[0003] However, traditional arc-shaped lines based on planar geometric models are difficult to adapt to three-dimensional packaging structures with vertical interconnect requirements. In traditional two-dimensional packaging processes, arcs typically take the form of arched or trapezoidal structures with a large horizontal span, and their formation process mainly relies on the trajectory control of the cutting edge within a two-dimensional plane. However, in advanced packaging scenarios such as high-level chip stacking, heterogeneous integration, and through-silicon via (TSV) assisted interconnection, there is an urgent need for three-dimensional arcs with high vertical segments, low horizontal spans, and excellent mechanical stability.

[0004] In existing technologies, in order to achieve a vertical arc shape, it is usually necessary to introduce additional auxiliary devices or make complex modifications to the equipment. This not only increases the equipment cost and process complexity, but also reduces process compatibility and production line adaptability.

[0005] Therefore, how to reliably form vertical arcs in three-dimensional space through process optimization and algorithm upgrades within the existing wire bonding machine equipment framework has become a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0006] To address the technical problem that the traditional wire arc shape in existing wire bonding processes is limited by two-dimensional geometric configuration and cannot meet the requirements of vertical interconnect spatial structure for three-dimensional stacked packaging, this application provides a method and system for forming three-dimensional vertical wire arcs in a wire bonding machine. This method does not require the introduction of any external hardware modules and achieves the formation of highly reliable three-dimensional wire arcs within the existing equipment framework by coordinating and controlling the mechanical action of the cutting blade and the multi-axis motion trajectory.

[0007] The technical solution is as follows:

[0008] On the one hand, a method for forming a three-dimensional vertical arc in a wire bonding machine is provided, including:

[0009] The cleaver moves to the firing height, performs the firing of the ball, and completes the welding of the first weld point;

[0010] After the first weld point is completed, the wire clamp is opened, and the cleaver is raised to the preset length required for the vertical arc.

[0011] The connector clamp is closed, the cleaver moves to the preset notch preparation position outside the solder pad, and the tip of the cleaver is controlled to press down on the wire to form a notch;

[0012] A dynamic multi-axis trajectory planning algorithm is used to control the cutting tool to return to the first welding point along the optimized trajectory and reserve the height of the line tail.

[0013] The control clamp closes and controls the splitter to lift along the Z-axis, causing the wire to stretch and break at the notch, forming a three-dimensional vertical arc with a vertical starting section and a preset tail height at the end.

[0014] Preferably, the step of controlling the tip of the cleaver to press down on the wire to form a notch includes:

[0015] Control the cleaving blade to quickly descend to a preset height;

[0016] Switch to force control mode to control the cutting blade to apply vertical pressure to the wire and slowly press it down. The preset pressure is between the yield strength and tensile strength of the wire.

[0017] Preferably, the step of using a dynamic multi-axis trajectory planning algorithm to control the cutting blade to return to directly above the first weld point along the optimized trajectory includes:

[0018] Construct equidistant three-dimensional spatial coordinate points between the notch preparation location and the coordinates of the first weld point;

[0019] A cubic polynomial curve is constructed between every two adjacent coordinate points, and adjacent curve segments have continuous second derivatives at the nodes to form a smooth three-dimensional spline curve as the optimized trajectory.

[0020] Preferably, the step of moving the cutting blade to the firing height, firing the ball, and completing the welding of the first weld point includes:

[0021] Control the chopping blade to raise the preset line end height and then lower it to the height of the burning ball;

[0022] A high-temperature electric arc is generated, which ablates and melts the end of the wire into a metal ball;

[0023] The driving blade is pressed down and ultrasonic vibration is applied to weld the metal ball onto the pad, forming the first solder joint.

[0024] Preferably, in the step of activating the high-temperature electric arc, the arc energy is determined by the following formula:

[0025] ;

[0026] in, This is the breakdown voltage. For ignition current, For ignition time, It is electric arc energy.

[0027] Preferably, during the process of the chopping blade moving to the preset notch preparation position outside the pad, the method further includes: while the motion platform drives the arc to move horizontally, controlling the chopping blade to perform a coordinated vertical movement.

[0028] Preferably, the coordinated vertical motion includes a high-speed approach phase and a precision force control phase;

[0029] During the high-speed approach phase, the system is in closed-loop position control, and the motor output force... Determined by the following formula:

[0030] ,

[0031] in, For position commands, For speed, For acceleration, To provide real-time location feedback, For the speed of the head, For PID ratio, For PID differential gain, For acceleration feedforward gain, This is the velocity feedforward gain.

[0032] Preferably, the step of closing the wire clamp and controlling the chopping blade to lift along the Z-axis, causing the wire to break at the notch and forming a three-dimensional vertical arc with a vertical starting section and a preset tail height at the end, includes:

[0033] After the cutting blade returns to directly above the first welding point, control the cutting blade to be raised along the Z-axis to the preset line end height;

[0034] Control clamp closure;

[0035] Control the chopping blade to pull upwards along the Z-axis, causing the wire to break at the notch.

[0036] Preferably, after the first weld point is completed, the wire clamp is opened, and the wedge is raised to the required length of the preset vertical arc, the method further includes: controlling the wire clamp to close to fix the wire.

[0037] On the other hand, a three-dimensional vertical arc forming system for a wire bonding machine is provided, comprising:

[0038] Motion control card, used to execute multi-axis trajectory planning algorithms, dynamics optimization algorithms, and process logic coordination;

[0039] Ignition module, used to form a molten ball at the end of the wire before welding;

[0040] The tool head and motion platform module are used to drive the vertical feed of the cutting tool, apply ultrasonic energy, and control the opening and closing of the wire clamp. The motion platform module is used to drive the tool head or the worktable to move in a two-dimensional plane.

[0041] A splitting blade and wire clamp assembly, wherein the splitting blade is used to apply downward pressure to the wire to form a notch, and the wire clamp is used to hold the wire to assist in breaking.

[0042] The technical solution includes at least the following technical effects:

[0043] By applying precise downward pressure to the wire using a real-time closed-loop control tool, a controlled micro-notch is induced at a preset position on the outside of the solder pad. The depth of this notch is rigorously calibrated to significantly reduce the local mechanical strength of the wire while maintaining the macroscopic continuity of the wire. This ensures the controllability of the fracture site during subsequent pulling and avoids thermomechanical damage to the ball-bundled structure of the first solder joint, thus guaranteeing the integrity of the solder joint interface strength.

[0044] By employing a highly dynamic multi-axis trajectory planning algorithm, the motion path of the cutting tool returning to the first welding point after completing the downward pressing operation is precisely guided. This trajectory is dynamically optimized to minimize lateral disturbance of the arc and maintain stable axial tension of the wire, ensuring that the arc maintains a near-ideal vertical orientation throughout the lifting phase, thereby achieving excellent arc perpendicularity and length consistency.

[0045] Specifically, after completing the ball welding process of the first solder point, the wedge moves the arc to a designated coordinate outside the solder pad and performs the above-mentioned controllable pressing process. Then, a dynamic multi-axis trajectory planning algorithm is used to return to the top of the first solder point along the optimized trajectory. Finally, the arc is cleanly broken at the pre-made weak gap by closing the wire clamp and directional lifting along the Z-axis, forming a three-dimensional vertical arc with a steep starting segment and good repeatability of shape.

[0046] This application achieves the dual goals of ensuring solder joint connection strength and wire arc geometry accuracy without adding new hardware modules through the above-mentioned strategy, significantly enhancing the adaptability of wire bonding equipment to three-dimensional advanced packaging processes and providing key process technology support for high-density heterogeneous integration.

[0047] It should be understood that the above general description and the following detailed description are merely exemplary and do not limit this application. Attached Figure Description

[0048] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0049] Figure 1 A flowchart of a method for forming a three-dimensional vertical arc in a wire bonding machine, provided in a preferred embodiment of this application;

[0050] Figure 2 A flowchart of a three-dimensional vertical arc forming method for a wire bonding machine is provided as another preferred embodiment of this application;

[0051] Figure 3 The image shows the trajectory of a vertical arc provided in a preferred embodiment of this application. Detailed Implementation

[0052] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0053] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0054] As attached Figure 1 As shown, in one embodiment, a method for forming a three-dimensional vertical arc in a wire bonding machine is provided, comprising the following steps:

[0055] The cutting tool moves to the ignition height, performs ignition to burn the wire end into a ball, and completes the first solder joint. Specific steps include: controlling the cutting tool to raise the wire end to a preset height and then lower it to the burning height; igniting a high-temperature arc to burn and melt the wire end into a metal ball; driving the cutting tool downwards and applying ultrasonic vibration to solder the metal ball onto the pad, forming the first solder joint. In the step of igniting the high-temperature arc, the arc energy... Determined by the following formula:

[0056] ;

[0057] in, This is the breakdown voltage. For ignition current, For ignition time, It is electric arc energy.

[0058] After the first weld point is completed, the wire clamp is opened, and the cutting tool is raised to the preset length required for the vertical arc. After the step of opening the wire clamp and raising the cutting tool to the preset length required for the vertical arc, the method further includes: controlling the wire clamp to close to fix the wire.

[0059] The connector clamp closes, and the wedge moves to a preset notch preparation position outside the pad. The wedge tip is controlled to press down on the wire to form a notch, which is used to reduce the local mechanical strength of the wire. The step of controlling the wedge tip to press down on the wire to form a notch includes: controlling the wedge to quickly descend to a preset height; switching to force control mode, controlling the wedge to apply vertical pressure to the wire and slowly press it down, the preset pressure being between the yield strength and tensile strength of the wire. During the process of the wedge moving to the preset notch preparation position outside the pad, it also includes: while the motion platform drives the wire arc to move horizontally, the wedge is controlled to perform a coordinated vertical movement. The coordinated vertical movement includes a high-speed approach stage and a precision force control stage.

[0060] During the high-speed approach phase, the system is in closed-loop position control, and the motor output force... Determined by the following formula:

[0061] ,

[0062] in, For position commands, and Their velocity and acceleration are respectively. To provide real-time location feedback, For the speed of the head, For PID ratio, For PID differential gain, For acceleration feedforward gain, This is the velocity feedforward gain.

[0063] A dynamic multi-axis trajectory planning algorithm is employed to control the cutting tool to return along an optimized trajectory to directly above the first weld point, reserving a height for the wire tail. The optimized trajectory is dynamically optimized with the goal of maintaining stable axial tension in the wire. Specific steps include: constructing equidistant three-dimensional spatial coordinate points between the notch preparation location and the coordinates of the first weld point; constructing a cubic polynomial curve between every two adjacent coordinate points, ensuring that adjacent curve segments have continuous second derivatives at the nodes to form a smooth three-dimensional spline curve, which serves as the optimized trajectory.

[0064] The bonding head controls the wire clamp to close and controls the chopping blade to rise along the Z-axis, causing the wire to stretch and break at the notch, forming a three-dimensional vertical arc with a vertical starting section and a preset tail height at the end. Specific steps include: after the chopping blade returns to directly above the first solder joint, controlling the chopping blade to rise again along the Z-axis to the preset tail height; the bonding head controls the wire clamp to close;

[0065] The control blade pulls the wire upward along the Z-axis, causing it to break at the notch.

[0066] In another embodiment, a three-dimensional spatial vertical arc forming system for wire bonding machines is deeply integrated into the architecture of semiconductor wire bonding machines. Its components include key subsystems such as a motion control card, an ignition module, a bonding head and motion platform module, and a cutting tool and wire clamp assembly. Through high-precision timing synchronization and closed-loop control between the modules, this system collaboratively achieves spatial arc forming suitable for three-dimensional stacked packaging, possessing excellent verticality and mechanical reliability.

[0067] The motion control card, as the core decision-making unit, is electrically connected to the tool head and motion platform module via bus or pulse commands. It sends multi-axis motion and force control commands to the tool head and planar positioning commands to the motion platform. The tool head integrates a Z-axis drive mechanism for the cutting blade, an ultrasonic transducer, and a wire clamp drive unit. It communicates with the motion control card to receive drive commands and mechanically connects the cutting blade and wire clamp, driving the cutting blade to perform vertical feed and the wire clamp to open and close. The motion platform module carries the tool head and drives it according to the commands from the motion control card. The bonding head moves in the horizontal plane; the host computer outputs instructions to the ignition module, whose high-voltage output terminal is electrically connected to the tip of the cleaver to generate a burning ball arc between the cleaver and the pad; the cleaver and the wire clamp assembly serve as terminal execution components. The cleaver is mechanically fixed to the Z-axis drive mechanism of the bonding head, and the wire clamp is fixed to the bonding head and holds the wire. Under the coordinated drive of the bonding head, the two complete the notch preparation and wire arc lifting and breaking. Thus, without adding external hardware, the reliable forming of a vertical wire arc in three-dimensional space is achieved through the timing synchronization and closed-loop control between the above modules.

[0068] As the core decision-making and command unit of the system, the motion control card undertakes key algorithmic functions such as multi-axis trajectory planning, dynamics optimization, and process logic coordination. Based on preset process parameters and real-time feedback signals, this module calculates the optimal motion path of the tool head and the cutting tool in the three-dimensional workspace and generates high-precision drive commands to each servo axis. Its control performance directly determines the smoothness of the motion process, positioning accuracy, and anti-interference capability in arc forming; it is the algorithmic cornerstone for ensuring the consistency and perpendicularity of the arc geometry.

[0069] The ignition module is responsible for forming the molten ball at the end of the metal wire before the first weld point is welded. This module typically consists of a high-voltage pulse generator, a controlled discharge electrode, and corresponding protection circuits. By generating a high-temperature arc with highly stable energy and repeatable spatiotemporal characteristics, it locally melts the end of the wire and forms a ball due to surface tension, providing the necessary metallurgical basis for the subsequent ultrasonic bonding to form a consistent and reliable spherical first weld point.

[0070] The bonding head and motion platform module together constitute the system's execution and positioning mechanism. As an integrated functional module, the bonding head internally integrates a precision Z-axis drive mechanism for the bonding cutter, an ultrasonic frequency transducer, and a wire clamp drive unit, enabling vertical feeding of the bonding cutter, application of ultrasonic energy, and control of wire clamp opening and closing. In the final arc forming stage, the bonding head precisely controls the wire clamp closure and performs directional lifting along the Z-axis, thereby completing the arc breakage forming. The motion platform typically employs a high-rigidity, low-inertia XY precision positioning platform, responsible for supporting the bonding head or worktable in performing high-speed, high-precision point-to-point movements within a two-dimensional plane. It is a key planar positioning subsystem ensuring that the bonding cutter accurately reaches the pad position, preset pressing point, and return path.

[0071] The cleaver and wire clamp assembly, as the terminal actuators that directly interact mechanically with the bonding wire, directly affect the process outcome. The cleaver is typically precision-machined from ultra-hard, wear-resistant materials such as special ceramics, and its tip guide hole structure serves both wire guiding and stress application functions. In the process described in this application, the cleaver, under controlled drive, precisely presses down on the wire, acting as a direct tool to induce a controllable micro-stress concentration notch at a predetermined location. The wire clamp, mounted above the cleaver, is responsible for clamping and releasing during the wire feeding stage. In the critical step of this application, it serves as the execution terminal for pull-out fracture. Through its reliable clamping and coordinated movement, it ensures that the wire arc fractures completely at the pre-made notch, thereby forming a vertical segment of the wire arc that meets design requirements.

[0072] As attached Figure 2 As shown, in another embodiment, a method for forming a three-dimensional vertical arc in a wire bonding machine is provided, the specific steps of which are as follows:

[0073] Initial positioning and wire tail reservation: First, perform initial positioning and wire tail reservation. After positioning the bonding head above the first solder point, raise the cutting tool along the Z-axis to the preset height. This is done to ensure the required wire length for subsequent burning of the ball. Then, the cleaver is lowered to the set height for burning the ball.

[0074] First solder joint welding: The ignition module generates a high-temperature arc between the tip of the cleaver and the solder pad according to the preset breakdown voltage and ignition current parameters. The generated arc energy is also related to the ignition time.

[0075] ;

[0076] in, This is the breakdown voltage. For ignition current, For ignition time, It is electric arc energy.

[0077] The wire tip is ablated and melted into an ideal metal sphere using a high-temperature electric arc. Then, the bonding head drives a cutting tool to press down at a set pressure. Simultaneously, an ultrasonic transducer applies vibration at a set frequency and amplitude. The combined effect of ultrasonic energy and downward pressure welds the metal sphere onto the pad, forming a stable first solder joint. Optionally, a grinding function can be activated at this time to smooth the shape of the solder ball.

[0078] Wire lifting and fixing: After the first weld point is completed, the wire clamp is opened, and the clamping head controls the cutting tool to vertically lift the wire along the Z-axis to the required length of the vertical arc. Subsequently, the clamp closes and fixes the line segment, preparing for the subsequent preparation of the gap and the formation of the line arc.

[0079] Notch preparation: The motion control card issues a control command, and the XY motion platform carries the solder head and moves together from the first solder point coordinates. Move to the preset wire notch preparation position To ensure that the arc remains smooth from beginning to end and is not overstretched or folded, while the XY motion platform moves the arc horizontally, the blade controls the chopping head to perform a coordinated vertical movement, which is divided into two processes: a high-speed approach stage and a precision force control stage.

[0080] High-speed approach phase: Assume the platform's horizontal movement time is... Then the cleaver needs to The system rapidly descends to the predetermined height. During this phase, the system operates in closed-loop position control, and the motor output force is related to the preset descent position. Determined by the following formula:

[0081] ;

[0082] in, For position commands, For speed, For acceleration, To provide real-time location feedback, For the speed of the head, For PID ratio, For PID differential gain, For acceleration feedforward gain, This is the velocity feedforward gain.

[0083] Precision force control stage: After the cutting blade quickly reaches the predetermined height, the system switches to the precision force control stage; the baffle controls the cutting blade to slowly press down with a small acceleration. During this process, the tip of the cutting blade applies vertical pressure to the wire. This pressure needs to be between the yield strength and tensile strength of the wire. Without shearing the wire, local deformation is generated, forming a micro-neck or notch with controlled depth, thereby significantly reducing the mechanical strength at that point.

[0084] Return trajectory optimization: During the return of the wire arc to the first solder joint driven by the connector and the XY motion platform, an ideal arc curve needs to be found in three-dimensional space to avoid buckling, folding, or additional compressive stress on the wire during the return process. In this embodiment, the trajectory adopts a spatial path based on a three-dimensional spline curve.

[0085] Wire notch preparation location and the coordinates of the first solder joint Construct equidistant Three-dimensional spatial coordinates In each interval Construct a cubic polynomial in the middle:

[0086] ;

[0087] in, , Constrain the starting point of each segment. For endpoint constraints.

[0088] If we make the second derivative of each segment continuous, then at the nodes;

[0089] ;

[0090] By solving for each segment of the spline curve, the trajectory path of the arc returning above the first solder joint can be calculated. This optimized trajectory aims to maintain the stability of the wire's axial tension while minimizing lateral disturbances of the arc.

[0091] Wire Arc Lifting and Breaking: After the cutter returns to directly above the first solder joint, the connector controls the cutter to lift along the Z-axis to the height required for the next ignition wire tail. Then, the wire clamp closes, firmly holding the wire. Finally, the connector pulls the wire upwards along the Z-axis.

[0092] Due to the reduced cross-sectional area and stress concentration at the notch, the wire will undergo controlled tensile fracture at this notch. After fracture, a fracture will form with a vertical starting segment and a total length of... And the end has a preset tail height. The complete three-dimensional vertical arc line prepares the subsequent arcing and balling cycle for the solder joints.

[0093] Experimental verification:

[0094] Figure 3 This diagram illustrates the trajectory of a vertical arc generated according to a preferred embodiment of this application. The red line represents the planned path, and the yellow line represents the actual path. The vertical axis represents the arc's displacement in the Z direction, i.e., its height; the horizontal axis represents the arc's displacement in the XY direction, i.e., its span. As can be seen from the diagram, the vertical arc generation method of this application exhibits very small trajectory errors. Furthermore, the error in the XY direction is minimal when the arc is lifted upwards at the end, ensuring the verticality of the arc.

[0095] The vertical arc formed using the method described in this application exhibits a steep vertical starting segment and a clear fracture end face, demonstrating excellent verticality and good morphological repeatability. By adjusting process parameters such as the required length and tail height of the vertical arc, the geometric dimensions of the arc can be precisely controlled to meet the vertical interconnection requirements of different three-dimensional packaging structures.

[0096] In summary:

[0097] This application is based on the core modules of existing wire bonding machines (motion control card, ignition module, bonding head, splitting blade, wire clamp, etc.), and achieves vertical arc forming through the coordinated optimization of process timing and energy modulation. It does not require the introduction of any external auxiliary devices, is easy to integrate into existing production lines, and lowers the technical application threshold.

[0098] By inducing a controlled micro-notch at a preset position on the outside of the pad, the depth of which is strictly calibrated, the local mechanical strength of the wire is significantly reduced while maintaining the macroscopic continuity of the wire. This ensures the controllability of the fracture site during the pulling process and avoids thermomechanical damage to the ball-welded structure of the first solder point, thus guaranteeing the integrity of the solder joint interface strength.

[0099] By using a high-dynamic multi-axis trajectory planning algorithm, the motion path of the cutting tool returning to the first welding point is precisely guided. With the goal of minimizing the lateral disturbance of the arc and maintaining the stability of the axial tension of the wire, the arc is ensured to maintain a near-ideal vertical orientation throughout the lifting stage, achieving excellent arc perpendicularity and length consistency.

[0100] This application addresses key interconnect challenges in 3D stacked packaging. It provides a reliable wire bonding solution for 3D stacked architecture processes, supporting the production of high-density integrated chip materials and finer-pitch pad layouts. From the perspective of the wire bonding machine industry, this solution is easily integrated into existing production lines, lowering the technical application threshold, promoting the industrial transition from 2D planar packaging to 3D packaging, and contributing to enhancing the overall technological autonomy and market adaptability of the industry chain.

[0101] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

Claims

1. A method for forming a three-dimensional vertical arc in a wire bonding machine, characterized in that, include: The cleaver moves to the firing height, performs the firing of the ball, and completes the welding of the first weld point; After the first weld point is completed, the wire clamp is opened, and the cleaver is raised to the preset length required for the vertical arc. The connector clamp is closed, the wedge moves to the preset notch preparation position outside the pad, and the wedge tip is controlled to press down on the wire to form a notch; the wedge is controlled to quickly descend to a preset height; switch to force control mode, and the wedge is controlled to apply vertical pressure to the wire and slowly press down, with the preset pressure between the yield strength and tensile strength of the wire; A dynamic multi-axis trajectory planning algorithm is adopted to control the cutting blade to return to the first weld point along the optimized trajectory and reserve the tail height; equidistant three-dimensional spatial coordinate points are constructed between the notch preparation position and the coordinates of the first weld point; a cubic polynomial curve is constructed between every two adjacent coordinate points, and the adjacent curve segments have continuous second derivatives at the nodes to form a smooth three-dimensional spline curve as the optimized trajectory. The control clamp closes and controls the splitter to lift along the Z-axis, causing the wire to stretch and break at the notch, forming a three-dimensional vertical arc with a vertical starting section and a preset tail height at the end.

2. The method for forming a three-dimensional vertical arc in wire bonding machine according to claim 1, characterized in that, The steps of moving the cutting blade to the firing height, firing the ball, and completing the first weld point welding include: Control the chopping blade to raise the preset line end height and then lower it to the height of the burning ball; An electric arc is generated, which ablates and melts the end of the wire into a metal ball; The driving blade is pressed down and ultrasonic vibration is applied to weld the metal ball onto the pad, forming the first solder joint.

3. The method for forming a three-dimensional vertical arc in wire bonding machine according to claim 2, characterized in that, In the step of activating the electric arc, the arc energy is determined by the following formula: ； in, This is the breakdown voltage. For ignition current, For ignition time, It is electric arc energy.

4. The method for forming a three-dimensional vertical arc in wire bonding machine according to claim 1, characterized in that, During the process of moving the chopping blade to the preset notch preparation position outside the pad, the method also includes: while the motion platform drives the arc to move horizontally, controlling the chopping blade to perform a coordinated vertical movement.

5. The method for forming a three-dimensional vertical arc in a wire bonding machine according to claim 4, characterized in that, The coordinated vertical motion includes a high-speed approximation phase and a precision force control phase; During the high-speed approach phase, the system is in closed-loop position control, and the motor output force... Determined by the following formula: ， in, For position commands, For speed, For acceleration, To provide real-time location feedback, For the speed of the head, For PID ratio, For PID differential gain, For acceleration feedforward gain, This is the velocity feedforward gain.

6. The method for forming a three-dimensional vertical arc in wire bonding machine according to claim 1, characterized in that, The steps of closing the wire clamp and controlling the chopping blade to lift along the Z-axis, causing the wire to break at the notch and forming a three-dimensional vertical arc with a vertical starting section and a preset tail height, include: After the cutting blade returns to directly above the first welding point, control the cutting blade to be raised along the Z-axis to the preset line end height; Control clamp closure; Control the chopping blade to pull upwards along the Z-axis, causing the wire to break at the notch.

7. The method for forming a three-dimensional vertical arc in a wire bonding machine according to claim 1, characterized in that, After the first weld point is completed, the wire clamp is opened, and the wedge is raised to the preset length required for the vertical arc, the method further includes: controlling the wire clamp to close to fix the wire.

8. A three-dimensional vertical arc forming system for a wire bonding machine, employing the three-dimensional vertical arc forming method for a wire bonding machine as described in any one of claims 1-7, characterized in that, include: Motion control card, used to execute multi-axis trajectory planning algorithms, dynamics optimization algorithms, and process logic coordination; Ignition module, used to form a molten ball at the end of the wire before welding; The tool head and motion platform module are used to drive the vertical feed of the cutting tool, apply ultrasonic energy, and control the opening and closing of the wire clamp. The motion platform module is used to drive the tool head or the worktable to move in a two-dimensional plane. A splitting blade and wire clamp assembly, wherein the splitting blade is used to apply downward pressure to the wire to form a notch, and the wire clamp is used to hold the wire to assist in breaking.

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