Multi-head synchronous bonding system and method

Abstract

The invention discloses a multi-head synchronous bonding system and method, and relates to the field of wafer-level system-level packaging. The system comprises a plurality of adjustable bonding heads arranged on the same X-Y axis motion platform; the Z-axis sharing module is internally provided with a high-precision linear motor and is used for synchronously driving a plurality of bonding heads to lift and realizing Z-axis position real-time feedback through a grating ruler; the bonding head adopts a modularized quick-release structure, and is mounted through a dovetail groove track, so that the stepless adjustment of the number and the spacing is realized; a laser distance measuring sensor, a voice coil motor-grating ruler closed-loop control mechanism, a force / temperature sensor and an AI algorithm module are further arranged and used for detecting and dynamically compensating the height, pressure and temperature of the bonding head in real time, and self-adaptive control and abnormal self-learning are achieved. The system supports expansion of multiple Z-axis-shared modules, achieves regional parallel operation through AI path planning, and is suitable for high-efficiency and high-precision bonding of large-size products. The invention further provides a corresponding bonding method, and the welding consistency and the production efficiency are further improved.

Description

Technical Field

[0001] This invention relates to the field of wafer-level system-in-package (SiP), specifically to a multi-head synchronous bonding system and method for wafer-level system-in-package (SiP), and is particularly suitable for high-density, high-precision packaging scenarios that require simultaneous ball bonding, wedge bonding, or hybrid bonding. Background Technology

[0002] The statements in this section are provided only as background information in connection with this disclosure and may not constitute prior art.

[0003] A wire bonding machine is a piece of equipment used in semiconductor manufacturing, specifically for electrically bonding metal wires to the leads of semiconductor chips to the substrate. Wire bonding processes are broadly classified into ball bonding and wedge bonding. Because these two types of bonding processes differ in hardware structure, software control, and process design, under normal circumstances, when a product requires both ball bonding and wedge bonding, separate ball bonding machines and wedge bonding machines are needed. Producing these separately is inefficient and costly.

[0004] For SiP products, since they are usually mounted in an array using carriers and the relative positional accuracy of the products is high, the design and manufacturing precision of the products themselves can reach the submicron level. Under these circumstances, multiple bonding heads can be planned on a single motion platform. Bonding heads with the same process or different processes can be installed to achieve simultaneous multi-head welding, improve production efficiency, and reduce equipment costs. Summary of the Invention

[0005] The purpose of this invention is to overcome the challenges of simultaneous ball bonding, wedge bonding, or single ball / single wedge bonding multi-head bonding in the design and fabrication of whole-wafer SiP products with high precision. This invention provides a multi-head synchronous bonding system and method that, by installing multiple bonding heads on the same motion platform, with adjustable bonding head positions, and by planning the wire spacing according to the actual product production, enables simultaneous multi-head bonding. The technical solution of the present invention is as follows: A multi-head synchronous bonding system, comprising: Multiple adjustable bonding heads are mounted on the same XY axis motion platform; the mounting position of the bonding heads can be adjusted along the XY axis motion platform to accommodate different wire bonding spacings. A common Z-axis module, which includes a high-precision linear motor drive mechanism for driving multiple bonding heads to move up and down synchronously; The grating ruler provides real-time feedback on the Z-axis position, ensuring motion accuracy of ≤±1μm.

[0006] Furthermore, the bonding head is a modular quick-release structure, which enables quick assembly and disassembly through mechanical and electrical interfaces.

[0007] Furthermore, the bonding head is mounted to the common Z-axis module via a dovetail groove track, enabling stepless adjustment of the number and spacing of the bonding heads.

[0008] Furthermore, it also includes: A laser rangefinder sensor is used to detect the height difference between the bonding head and the wafer surface in real time. The voice coil motor-grating ruler closed-loop control mechanism dynamically compensates for the height difference of the cutting tool, so that the working planes of each bonding head are consistent.

[0009] Furthermore, the laser rangefinder is also used to measure the height difference at the welding position and feed the height information back to the system to optimize the welding path planning.

[0010] Furthermore, the bonding head is equipped with a flexible Z-axis structure, including a linear guide rail and a spring buffer, with a flexible stroke of up to 1mm. The bonding head can be lifted independently by a voice coil motor to support single-head debugging or independent operation.

[0011] Furthermore, it also includes: Force sensors are used to monitor bonding pressure in real time; Temperature sensor for real-time monitoring of bonding temperature; The AI ​​algorithm module is used to dynamically adjust bonding parameters based on bonding pressure, temperature, and displacement data, enabling adaptive compensation and anomaly self-learning.

[0012] Furthermore, the force sensor is also used for automated force calibration, and the temperature sensor is also used for environmental anomaly early warning and equipment protection.

[0013] Furthermore, it supports the expansion of multiple common Z-axis modules. Through AI path planning to optimize motion trajectories, the system can control each common Z-axis module individually, plan the movement of different common Z-axis modules in specific areas, and plan the actions of different common Z-axis modules at different positions at the same time. This ensures that the movements of each module do not interfere with each other and that each module can move continuously, thereby achieving the goal of adapting to the regional bonding of large-size products and improving production efficiency.

[0014] This invention also proposes a multi-head synchronous bonding method, based on the above-mentioned multi-head synchronous bonding system, comprising: Adjust the bond head spacing to match the wire bonding layout; Laser ranging and closed-loop control ensure consistent blade height; By utilizing multi-sensor data and AI algorithms to optimize bonding parameters in real time, parallel high-precision welding can be achieved.

[0015] Compared with existing technologies, the advantages of this invention are: 1. Improved bonding efficiency: By setting multiple adjustable bonding heads on the same XY motion platform, multi-head parallel operation can be achieved. Compared with traditional single bonding head equipment, the bonding efficiency can be increased by N times (N is the number of bonding heads), which is particularly suitable for array-type high-density packaging of wafer-level SiP products.

[0016] 2. Enhanced system adaptability: The bonding head adopts a modular quick-release structure and is installed through a dovetail groove track, which enables stepless adjustment of the number and spacing of bonding heads. It can flexibly adapt to different wire bonding layouts and product specifications, and improve the equipment's versatility and reconfigurability.

[0017] 3. Ensure bonding consistency: The height difference between the bonding head and the wafer surface is detected in real time by a laser rangefinder sensor. Combined with the voice coil motor-grating ruler closed-loop control mechanism, the height of the cleaving tool is dynamically compensated to ensure that the working plane of each bonding head is consistent, effectively eliminating the problem of uneven bonding quality caused by height deviation.

[0018] 4. Achieve high-precision control: The Z-axis is driven by a high-precision linear motor, with real-time feedback from a grating ruler, ensuring Z-axis motion accuracy ≤ ±1μm; the flexible Z-axis structure combined with a voice coil motor enables independent adjustment and precise force control of the single-key connector, meeting sub-micron level packaging accuracy requirements.

[0019] 5. Supports intelligent control and self-learning: The system integrates force sensors, temperature sensors and AI algorithm modules, which can monitor pressure, temperature and displacement data in real time during the bonding process, dynamically adjust bonding parameters, realize adaptive compensation and anomaly self-learning, reduce manual intervention and improve system stability and reliability.

[0020] 6. Suitable for large-size products and multi-area operations: Supports expansion of multiple Z-axis modules, combined with AI path planning, to achieve independent control and parallel operation of different areas, avoid motion interference between modules, meet the regional bonding requirements of large-size products, and further improve production efficiency and equipment utilization.

[0021] 7. Improved debugging and maintenance efficiency: The flexible Z-axis structure allows for the individual lifting of any bonding head, supporting single-head debugging, maintenance, or troubleshooting, reducing equipment downtime, and improving maintenance efficiency and ease of operation. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the common Z-axis module structure; Figure 2 This is a schematic diagram of a ball-welded / wedge-welded bond head structure; Figure 3 A schematic diagram of the layout of multiple Z-axis modules in a large-area array product; Figure 4 An adaptive correction logic diagram for real-time analysis of bonding forces.

[0023] Reference numerals: 1-Common Z-axis module, 2-Ball bonding head, 3-Wedge bonding head, 4-Beat product, 11-Dovetail guide rail, 21-Bond head mounting part, 22-Voice coil motor, 23-Grating ruler, 24-Flexible Z-axis structure, 25-Cleaver, 26-Laser rangefinder sensor. Detailed Implementation

[0024] It should be noted that relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0025] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0026] Example 1 A multi-head synchronous bonding system, comprising: Multiple adjustable bonding heads are mounted on the same XY-axis motion platform. The mounting position of the bonding heads can be adjusted along the XY-axis motion platform to accommodate different wire spacings. In other words, the mounting position of multiple adjustable bonding heads can be adjusted to accommodate different wire spacing plans. Multiple bonding heads are installed on the same XY-axis motion platform, and their mounting positions are adjustable. The bonding heads are installed according to the wire spacing planned for the actual products being produced, enabling simultaneous welding of multiple heads. The adjustable mounting position of the bonding heads can adapt to adjustments in the wire spacing plan within a certain range. A common Z-axis module is provided, which is equipped with a common Z-axis high-precision linear motor drive mechanism to drive multiple bonding heads to rise and fall synchronously, so as to avoid bonding offset caused by asynchronous movement. The grating ruler provides real-time feedback on the Z-axis position, ensuring a motion accuracy of ≤±1μm; that is, the Z-axis position is fed back in real time through the grating ruler to ensure a motion accuracy of ≤±1μm.

[0027] In this embodiment, the bonding head is a modular quick-release structure, which enables quick assembly and disassembly through mechanical and electrical interfaces.

[0028] In this embodiment, specifically, the bonding head is installed to the common Z-axis module via a dovetail groove track, enabling stepless adjustment of the number and spacing of the bonding heads; thus, flexible spacing adjustment and multiple installations can be achieved.

[0029] In this embodiment, it should also be noted that, depending on the product size, the number of bonding heads can be adjusted by utilizing the submicron-level relative positional accuracy of the array products on the wafer. By installing multiple bonding heads with a fixed spacing, array bonding of multiple SiP products can be achieved, which improves efficiency by N times (N is the number of bonding heads) compared to single bonding head equipment.

[0030] In this embodiment, specifically, it also includes: A laser rangefinder sensor is used to detect the height difference between the bonding head and the wafer surface in real time. The voice coil motor-grating ruler closed-loop control mechanism dynamically compensates for the height of the cutting tool based on the height difference, so that the working planes of each bonding head are consistent. The bonding head is also equipped with a laser rangefinder to detect the relative distance between the bonding head and the product in real time. Through distance detection and real-time feedback from the voice coil motor and grating ruler, the relative height of the wedges on the bonding head is compensated in real time to ensure that the wedge height of each bonding head is consistent during actual welding. This ensures that multiple bonding heads are on the same working plane when contacting the wafer, effectively eliminating the problem of inconsistent bonding quality caused by height deviation.

[0031] In this embodiment, specifically, the laser rangefinder is also used to measure the height difference of the welding position and feed the height information back to the system to optimize the welding path planning; that is, the laser rangefinder on the bonding head can also be used to measure the height difference of the product welding position in real time and feed the welding position height back to the system to achieve advance planning during welding.

[0032] In this embodiment, specifically, the bonding head is provided with a flexible Z-axis structure, including a linear guide rail and a spring buffer, with a flexible stroke of 1 mm, and the bonding head can be lifted separately by a voice coil motor to support single-head debugging or independent operation; The bonding head adopts a flexible Z-axis structure with linear guide rails and springs, with a Z-axis flexible distance of 1mm. It includes a voice coil motor to control the position of the bonding head. When adjusting the parameters of a single bonding head, the voice coil motor can be used to control the other bonding heads to be raised by 1mm, so as to adjust the parameters of a single bonding head or the usage of a single bonding head. Preferably, the flexible Z-axis structure is powered by a voice coil motor and uses a grating ruler on the bonding head for position feedback, so as to achieve precise control of the Z-height of the bonding head.

[0033] In this embodiment, including but not limited to a single common Z-axis module, the number of common Z-axis modules can be increased when adapting to large-size products. By planning the motion paths of different common Z-axis modules, the efficiency of the equipment can be further improved. By initially planning the path manually and feeding data, AI algorithms are then applied to similar products, allowing AI to perform optimal path planning, thereby improving programming efficiency, reducing manual operations, and fulfilling further industrial automation needs.

[0034] In this embodiment, specifically, it also includes: Force sensors are used to monitor bonding pressure in real time; Temperature sensor for real-time monitoring of bonding temperature; The AI ​​algorithm module is used to dynamically adjust bonding parameters based on bonding pressure, temperature and displacement data to achieve adaptive compensation and anomaly self-learning. This involves adding force and temperature sensors to each bonding head to simultaneously monitor bonding pressure, displacement, and temperature changes during the bonding process. AI algorithms are used to analyze multi-source data in real time and dynamically adjust compensation parameters to achieve adaptive correction of the bonding head height. This can be used for AI self-learning and parameter self-adjustment in case of bonding head malfunctions, thus solving the problem of all bonding heads being shut down due to manual intervention when a single bonding head malfunctions.

[0035] In this embodiment, specifically, the force sensor is also used for automated force calibration, and the temperature sensor is also used for environmental anomaly early warning and equipment protection; That is, the force sensor can detect the actual pressure of the bonding head in real time, and provide timely feedback and adjustment if any abnormality occurs, and can perform automated force calibration; The temperature sensor can detect the ambient temperature in real time and provide timely feedback if any abnormality occurs, thus protecting the equipment and products.

[0036] In this embodiment, it should be noted that the voice coil motor has high motion precision and fast response speed, achieving millisecond-level response time. Due to its simple structure and lack of mechanical contact parts, the voice coil motor has a long lifespan and high operational stability. Compared with traditional motors, it is small in size and can be used in relatively confined spaces, making the overall structure more compact and facilitating the precision machining of semiconductor workpieces.

[0037] In this embodiment, specifically, it supports the expansion of multiple common Z-axis modules. By optimizing the motion trajectory through AI path planning, the system controls each common Z-axis module individually, plans the movement of different common Z-axis modules in specific areas, and plans the actions of different common Z-axis modules at different positions at the same time. This achieves the goal of ensuring that the movements of each module do not interfere with each other and that each module can move continuously, thereby adapting to the regional bonding of large-size products and improving production efficiency.

[0038] This embodiment also proposes a multi-head synchronous bonding method, based on the above-described multi-head synchronous bonding system, including: Adjust the bond head spacing to match the wire bonding layout; Laser ranging and closed-loop control ensure consistent blade height; By utilizing multi-sensor data and AI algorithms to optimize bonding parameters in real time, parallel high-precision welding can be achieved.

[0039] Example 2 The present invention will be further illustrated by way of embodiments below, but the present invention is not limited to the scope of the embodiments described herein.

[0040] like Figure 1 This embodiment discloses an equipment solution, which includes a multiple bonding head installation scheme for a common Z-axis module 1. It adopts a quick-release mechanical + electrical interface, and the bonding head is installed on the common Z-axis module 1 through the dovetail guide rail 11 to achieve quick disassembly and adjustment.

[0041] In this embodiment, the bonding head can be steplessly adjusted along the entire dovetail groove guide rail 11, covering the entire length of the guide rail and achieving full-size coverage of the entire common Z-axis module 1.

[0042] In this example, it is not limited to installing one ball bonded head 2 and one wedge bonded head 3. More bonded heads can be installed, or multiple bonded heads of the same type can be installed as needed.

[0043] Specifically, such as Figure 2 As shown, the bonding head includes: Dovetail groove track mounting base for quick connection with common Z-axis module 1; The voice coil motor 22 is located above the flexible Z-axis structure 24, which can accurately control the force of the flexible Z-axis structure 24-cleaver 25. The force control accuracy can reach ±0.5g, and the force output range can reach 0-250g; it can perfectly meet the pressure accuracy required during welding. The grating ruler 23 is a high-precision glass grating ruler 23 with a resolution of up to 0.05um. The grating ruler 23 can read the Z-axis position of the flexible Z-axis structure 24 of the bonding head and provide real-time feedback to the motion system. It can accurately control the actual height of the splitting blade 25. The flexible Z-axis structure 24 can achieve a vertical movement of 1mm in the Z-axis direction. The large flexible distance is used to adjust the height difference of the multi-head splitting blade 25. The 1mm height movement range can perfectly adapt to the height difference designed for the bonded product 4, achieving reliable bonding.

[0044] Specifically, such as Figure 2As shown, each bonding head is equipped with a laser rangefinder 26. The laser rangefinder 26 has a distance accuracy of up to 1µm and is used to detect the height difference between each bonding head and the plane of the product 4 being bonded in real time. The laser rangefinder 26 is installed on each bonding head according to standard requirements to ensure that the relative distance between the sensor sensing plane and the head of the wedge 25 is constant. This allows the wedge 25 to move perfectly to the position height detected by the laser rangefinder 26, solving the problem of contact overshoot between the wedge 25 and the product 4 caused by bonding head height differences due to manufacturing tolerances and wafer unevenness, and protecting the product 4 from damage due to overshoot.

[0045] Specifically, such as Figure 3 As shown, the equipment can also install multiple common Z-axis modules 1 (two are shown in the example in the figure), which can be adapted to large-area array products. Through pre-programming, the production area and production path of each common Z-axis module 1 can be planned, ensuring that each Z-axis does not interfere with the others, and completing a flexible multi-head array within the planned area, further improving production efficiency. For bonding products 4 of different sizes, different numbers of common Z-axis modules 1 can be installed, achieving the optimal design of efficiency and rationality.

[0046] Specifically, such as Figures 1-3 As shown, each Z-axis module 1 is independent of each other. Each bonding head in each module is equipped with a flexible Z-axis structure 24. The flexible Z-axis structure 24 can move 1mm in the Z direction. When multiple bonding heads are bonding at the same time, it can solve the problems of inconsistent height of the bonded products 4 and inconsistent height of the bonding heads caused by manufacturing tolerances.

[0047] Specifically, such as Figures 1-3 As shown, when multiple bonding heads are installed, the flexible Z-axis structure 24 can move 1mm in the Z direction by using a voice coil (voice coil motor 22 can output a vertically upward force) to lift all bonding heads except the one to be adjusted by 1mm. This allows for the early process debugging, mid-term maintenance, and repair of individual bonding heads when problems occur.

[0048] The embodiments described above merely illustrate specific implementation methods of this application, and while the descriptions are detailed and specific, they should not be construed as limiting the scope of protection of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the technical solution of this application, and these modifications and improvements all fall within the scope of protection of this application.

[0049] This background section is provided to generally present the context of the invention. The work of the currently named inventors, the work to the extent described in this background section, and aspects of this section that did not constitute prior art at the time of application are neither expressly nor impliedly acknowledged as prior art to the invention.

Claims

1. A multi-head synchronous bonding system, characterized in that, include: Multiple adjustable bonding heads are mounted on the same XY axis motion platform; the mounting position of the bonding heads can be adjusted along the XY axis motion platform to accommodate different wire bonding spacings. A common Z-axis module, which includes a high-precision linear motor drive mechanism for driving multiple bonding heads to move up and down synchronously; The grating ruler provides real-time feedback on the Z-axis position, ensuring motion accuracy of ≤±1μm.

2. The multi-head synchronous bonding system according to claim 1, characterized in that, The bonding head is a modular quick-release structure, which enables quick assembly and disassembly through mechanical and electrical interfaces.

3. The multi-head synchronous bonding system according to claim 2, characterized in that, The bonding head is mounted to the common Z-axis module via a dovetail groove track, enabling stepless adjustment of the number and spacing of the bonding heads.

4. A multi-head synchronous bonding system according to claim 3, characterized in that, Also includes: A laser rangefinder sensor is used to detect the height difference between the bonding head and the wafer surface in real time. The voice coil motor-grating ruler closed-loop control mechanism dynamically compensates for the height difference of the cutting tool, so that the working planes of each bonding head are consistent.

5. A multi-head synchronous bonding system according to claim 4, characterized in that, The laser rangefinder is also used to measure the height difference at the welding position and feed the height information back to the system to optimize the welding path planning.

6. A multi-head synchronous bonding system according to claim 5, characterized in that, The bonding head has a flexible Z-axis structure, including a linear guide rail and a spring buffer, with a flexible stroke of up to 1 mm. The bonding head can be lifted independently by a voice coil motor to support single-head debugging or independent operation.

7. A multi-head synchronous bonding system according to claim 6, characterized in that, Also includes: Force sensors are used to monitor bonding pressure in real time; Temperature sensor for real-time monitoring of bonding temperature; The AI ​​algorithm module is used to dynamically adjust bonding parameters based on bonding pressure, temperature, and displacement data, enabling adaptive compensation and anomaly self-learning.

8. A multi-head synchronous bonding system according to claim 7, characterized in that, The force sensor is also used for automated force calibration, and the temperature sensor is also used for environmental anomaly early warning and equipment protection.

9. A multi-head synchronous bonding system according to claim 8, characterized in that, It supports the expansion of multiple common Z-axis modules, optimizes motion trajectories through AI path planning, and controls each common Z-axis module individually, planning the movement of different common Z-axis modules in specific areas. At the same time, it plans the actions of different common Z-axis modules at different positions, so that the movement of each module does not interfere with each other and can keep each module moving continuously. This achieves the purpose of adapting to the regional bonding of large-size products and improving production efficiency.

10. A multi-head synchronous bonding method, characterized in that, A multi-head synchronous bonding system according to any one of claims 1-9 includes: Adjust the bond head spacing to match the wire bonding layout; Laser ranging and closed-loop control ensure consistent blade height; By utilizing multi-sensor data and AI algorithms to optimize bonding parameters in real time, parallel high-precision welding can be achieved.

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