Laser marking and automatic detection system

Abstract

The utility model discloses a kind of laser marking and automatic detection system, including rack, platform, image recognition positioning unit, processing measurement integrated module, motion module and control system.The hollow area is equipped in the middle of the platform;Image recognition positioning unit is located above platform and aligns the hollow area;The processing measurement integrated module is located below platform, and integrated laser marking unit and laser depth measurement unit;The motion module is transmission connected with the integrated module, for driving its movement.The utility model integrates by marking and measurement function in one, and by motion module driving cooperative work, realizes marking, depth measurement, quality judgment and the full-process automation closed-loop control of feedback, fundamentally solves the technical problem of traditional offline detection inefficiency, feedback lag, significantly improves the intelligent level of semiconductor wafer marking and product quality consistency.

Description

Technical Field

[0001] This utility model belongs to the field of semiconductor precision equipment technology, and relates to a laser marking and automatic detection system. Background Technology

[0002] In semiconductor wafer packaging processes, laser marking technology is widely used on the surface or back of wafers due to its permanent, high-precision, and non-contact characteristics. It is used to imprint permanent markings containing information such as QR codes, data matrices, or text. These markings provide each chip (die) with traceable and unique identification information, which is of great significance for enabling full lifecycle tracking, classification, yield analysis, process optimization, and anti-counterfeiting security.

[0003] Currently, the conventional approach in this technology is as follows: first, laser marking equipment is used to etch the markings onto the wafer. Then, the wafer is transferred to a separate, offline measuring device (such as an optical profilometer or confocal microscope) to inspect the depth of the marked characters. Marking depth is a core critical parameter for measuring marking quality, and it typically needs to be strictly controlled within the range of 1–20 micrometers. Too shallow a depth may cause the markings to be removed in subsequent processes, resulting in information loss; too deep a depth may damage the wafer substrate, causing reliability issues such as microcracks.

[0004] However, this traditional production model of "marking first, then measuring offline" has obvious drawbacks: (1) Low production efficiency: Marking and measurement are two separate processes. Wafers need to be moved, positioned and aligned multiple times between different devices. The whole process has many links, which seriously restricts the overall efficiency of the production line. (2) Delayed quality feedback: The depth measurement results cannot be fed back to the marking process in real time. When the depth does not meet the specifications, the marking process parameters cannot be adjusted immediately, which may cause defective batches to flow into the subsequent packaging process, causing greater losses. (3) Insufficient automation: The entire detection and judgment process is highly dependent on manual operation, which not only increases labor costs, but also introduces the risk of human misjudgment, which is not conducive to the construction of intelligent manufacturing production lines. (4) High overall quality risk: Due to the lack of online and real-time quality monitoring, the fluctuations in the marking process cannot be captured and corrected in time, which poses a potential threat to the reliability and consistency of the final product.

[0005] Therefore, there is an urgent need in this field to solve the above problems and achieve online, real-time control of marking quality, thereby comprehensively improving the production efficiency and product quality of semiconductor manufacturing.

[0006] It should be noted that the above introduction to the technical background is only for the purpose of providing a clear and complete explanation of the technical solutions of this application and facilitating understanding by those skilled in the art. It should not be assumed that these technical solutions are known to those skilled in the art simply because they have been described in the background section of this application. Utility Model Content

[0007] In view of the shortcomings of the prior art described above, the purpose of this utility model is to provide a laser marking and automatic inspection system that can deeply integrate laser marking and depth measurement functions, realize online and real-time control of marking quality, and thus comprehensively improve the production efficiency and product quality of semiconductor manufacturing.

[0008] To achieve the above objectives, this utility model provides a laser marking and automatic inspection system, the laser marking and automatic inspection system comprising:

[0009] frame;

[0010] A stage, which is fixed on a frame and used to support wafers, has a hollow area in the middle that runs through the upper and lower surfaces of the stage;

[0011] An image recognition and positioning unit is located above the platform, with its camera facing the hollowed-out area.

[0012] A processing and measurement integrated module is disposed below the stage, and the processing and measurement integrated module integrates a laser marking unit and a laser depth measurement unit; the marking optical path of the laser marking unit is aligned with the hollowed-out area, and the measurement optical path of the laser depth measurement unit is aligned with the hollowed-out area;

[0013] The motion module is connected to the processing and measurement integrated module via a transmission connection;

[0014] Control system

[0015] Both the laser marking unit and the laser depth measurement unit are communicatively connected to the control system.

[0016] Optionally, the image recognition positioning unit has a dome-shaped structure and its inner wall is provided with a high-reflectivity mirror.

[0017] Optionally, the processing and measurement integrated module includes a horizontal mounting plate, on which the laser marking unit and the laser depth measurement unit are fixed side by side.

[0018] Optionally, a direct signal connection channel is provided between the laser marking unit and the laser depth measurement unit; the distance between the measurement optical path and the marking optical path is less than or equal to the distance between two adjacent marking positions on the platform.

[0019] Optionally, the processing and measurement integrated module is a functional head; the laser marking unit and the laser depth measurement unit are integrated inside the functional head in a switchable manner; the functional head is configured to switch between the marking optical path and the measurement optical path.

[0020] Optionally, the functional head is mounted on the functional base plate via a rotating shaft; the functional base plate is fixed to the motion module by bolts.

[0021] Optionally, the motion module is an XY cross slide.

[0022] Optionally, the laser depth measurement unit includes a laser confocal displacement sensor.

[0023] Optionally, the control system includes either a programmable logic controller (PLC) or an industrial computer (IPC).

[0024] Optionally, the control system communicates with an alarm device, which is an audible and visual alarm.

[0025] This utility model discloses a laser marking and automatic inspection system, including a frame, a stage, an image recognition and positioning unit, a processing and measurement integrated module, a motion module, and a control system. The stage has a hollowed-out area in the middle; the image recognition and positioning unit is located above the stage and aligned with the hollowed-out area; the processing and measurement integrated module is located below the stage and integrates a laser marking unit and a laser depth measurement unit; the motion module is drively connected to the integrated module to drive its movement. This utility model integrates marking and measurement functions into one unit, driven by a motion module for collaborative operation, achieving fully automated closed-loop control of the entire process of marking, depth measurement, quality judgment, and feedback. It fundamentally solves the technical problems of low efficiency and delayed feedback in traditional offline inspection, significantly improving the intelligence level and product quality consistency of semiconductor wafer marking. Attached Figure Description

[0026] Figure 1 The diagram shown is a schematic representation of the overall structure of the laser marking and automatic detection system provided by this utility model.

[0027] Figure 2 The diagram shows the relationship between the processing and measurement integrated module and the motion module of this utility model.

[0028] Figure 3 The diagram shown is a structural schematic of the functional head in the processing and measurement integrated module of this utility model.

[0029] Component designation explanation

[0030] 100 motion module 110 abutment 120 slide rail 130 slider 131 bolt 200 frame 300 Machining Measurement Integration Module 310 Laser marking unit 311 Marking optical path 312 Marking signal channel 313 First connection channel 314 Image recognition signal channel 320 Laser depth measurement unit 321 Measurement optical path 322 Measurement signal channel 330 Mounting plate 340 Function head 350 Rotation axis 360 Functional base plate 400 Platform 410 wafer 500 Image recognition and positioning unit 600 control system 610 alarm device Detailed Implementation

[0031] The following specific examples illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. This utility model can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this utility model.

[0032] It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of this utility model. Therefore, the drawings only show the components related to this utility model and are not drawn according to the actual number, shape and size of the components. In actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0033] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0034] Example

[0035] See Figures 1-3 This utility model discloses a laser marking and automatic detection system, including a frame 200, a platform 400, an image recognition and positioning unit 500, a processing and measurement integrated module 300, a laser marking unit 310, a motion module 100, and a control system 600.

[0036] The stage 400 is fixed on the frame 200 and is used to support the wafer 410. The stage 400 has a hollow area in the middle that runs through the upper and lower surfaces of the stage 400. The image recognition and positioning unit 500 is located above the stage 400, and the camera of the image recognition and positioning unit 500 is facing the hollow area. The processing and measurement integrated module 300 is located below the stage 400, and the processing and measurement integrated module 300 integrates a laser marking unit 310 and a laser depth measurement unit 320. The marking optical path 311 of the laser marking unit 310 is aligned with the hollow area, and the measurement optical path 321 of the laser depth measurement unit 320 is aligned with the hollow area. The motion module 100 is connected to the processing and measurement integrated module 300. Both the laser marking unit 310 and the laser depth measurement unit 320 are communicatively connected to the control system 600.

[0037] Specifically, this system integrates multiple functions—wafer 410 support, visual positioning, laser processing, and online measurement—through a three-dimensional layout of "top-down marking" and the hollow design of the stage 400. Its main function is as follows: After high-precision initial positioning using the image recognition positioning unit 500, the marking optical path 311 and the measurement optical path 321 can perform marking and depth detection on the wafer 410 through the hollow area, ensuring the consistency of process coordinates. After laser marking, the marking effect can be non-destructively inspected using the laser depth measurement unit 320, achieving "processing as inspection." This realizes a closed-loop processing system of "positioning-processing-real-time measurement-feedback compensation," fundamentally improving the accuracy, consistency, and intelligence level of processing.

[0038] For details, please refer to Figure 1 The stage 400 is fixed to the frame 200 by fasteners, providing a stable reference plane for all subsequent operations. A hollowed-out area extending through the upper and lower surfaces of the stage 400 is provided in the center of the stage. This hollowed-out area physically constitutes a shared optical working area, allowing the image recognition and positioning unit 500 located above the stage 400 and the processing and measurement integrated module 300 located below to perform operations on the wafer 410 through this area, thus achieving the basis for collaborative "top-down marking" work in spatial layout.

[0039] Furthermore, the image recognition and positioning unit 500 is fixed to the frame 200, and the optical axis of its high-resolution camera is set vertically to face the cutout area below. This design ensures that the image recognition and positioning unit 500 can scan the dicing and chip patterns on the front side of the wafer 410 through the cutout area from top to bottom without any obstruction, achieving high-precision visual positioning and providing a precise coordinate reference for the laser processing below.

[0040] As an example, the image recognition and positioning unit 500 has a dome-shaped structure and its inner wall is provided with a high-reflectivity mirror.

[0041] See Figure 1 The image recognition and positioning unit 500 adopts a dome-shaped structure, with its illumination source (such as an LED ring) located at the edge of the dome and its inner wall coated with a high-reflectivity material, thereby forming a non-directional, uniformly diffused light field to evenly illuminate the wafer 410 from all directions. This light field effectively eliminates directional shadows and local overexposure, thus obtaining a high-contrast, clearly defined chip pattern image. This not only enables the image sensor to stably capture high-quality images but also fundamentally improves positioning accuracy and repeatability, avoiding recognition errors caused by uneven illumination and providing a stable and reliable coordinate reference for subsequent laser marking. Of course, the structure of the image recognition and positioning unit 500 is not limited to this.

[0042] For further details, please refer to [link / reference]. Figure 1 In the processing and measurement integrated module 300, the marking optical path 311 of the laser marking unit 310 and the measurement optical path 321 of the laser depth measurement unit 320 are both calibrated and precisely aligned with the hollowed-out area. By integrating the marking and measurement functions into the same module, the traditional model of two independent and dispersed units in equipment is broken. This integrated design brings advantages such as compact structure, reduced equipment size, and avoidance of the accumulation of multiple positioning errors, while overcoming the problem of lagging quality feedback in existing technologies.

[0043] As an example, the processing measurement integrated module 300 includes a horizontal mounting plate 330, on which the laser marking unit 310 and the laser depth measurement unit 320 are fixed side by side.

[0044] For details, please refer to Figures 1-3 The mounting plate 330 serves as a shared rigid reference platform, on which the laser marking unit 310 and the laser depth measurement unit 320 are mounted side-by-side and fixed, ensuring that both move synchronously as a whole under the drive of the motion module 100. This design not only eliminates repetitive positioning errors and achieves efficient collaboration of "marking and measuring immediately," but also improves system rigidity, positioning accuracy, and maintenance convenience through modularity. Furthermore, this modular design simplifies the complex problem of multi-unit integration into the manufacturing and assembly of a standard mounting plate 330 component. It is not only compact, highly rigid, and has strong anti-interference capabilities, but also facilitates overall installation, debugging, and even future replacement and maintenance as a single module, improving the reliability and serviceability of the equipment. Of course, the integration mode of the processing and measurement integration module 300 is not limited to this.

[0045] As an example, a direct signal connection channel is provided between the laser marking unit 310 and the laser depth measurement unit 320; the distance between the measurement optical path 321 and the marking optical path 311 is less than or equal to the distance between two adjacent marking positions on the stage 400.

[0046] See Figure 2 This embodiment achieves efficient integration of marking and measurement processes through a dual collaborative design of signal and space. Firstly, regarding signal connection, a first connection channel 313 is provided between the laser marking unit 310 and the depth measurement unit, enabling the signal from completed marking to be transmitted without delay, providing hardware support for "real-time measurement" and minimizing waiting time between processes. Secondly, regarding structural design, see [reference needed]. Figure 2 In this design, the distance between the measuring optical path 321 and the marking optical path 311 is D1, and the adjacent marking positions are P1 and P2, with a distance of D2 between P1 and P2. D1 is less than or equal to D2, ensuring that after marking at a position (such as P1), only a small distance (D1) less than or equal to the normal processing step (D2) is needed for the measuring optical path 321 to accurately cover the marked position. This embeds the measurement process into the marking interval, avoiding idle movement for individual measurements. This optimizes the workflow in both time and space, and is the core of achieving high-efficiency online inspection. Of course, the arrangement relationship between the laser marking unit 310 and the laser depth measuring unit 320 is not limited to this.

[0047] As an example, the processing and measurement integrated module 300 includes a functional head 340; the laser marking unit 310 and the laser depth measurement unit 320 are integrated inside the functional head 340; the functional head 340 is configured to switch between the marking optical path 311 and the measurement optical path 321.

[0048] See Figure 3 The processing and measurement integrated module 300 can be specifically implemented as a functional head 340, which is an independent and enclosed mechatronic unit. Its core lies in the high-density integration of the laser marking unit 310 and the laser depth measurement unit 320 in a switchable manner, achieving time-division multiplexing of the two functions. This design achieves extreme compactness in space, eliminates mutual interference between the marking and measurement processes through physical isolation, and serves as a pre-calibration module to ensure long-term stability and accuracy, providing a highly integrated detection solution for the system. Of course, the integration mode of the processing and measurement integrated module 300 is not limited to this.

[0049] As an example, the functional head 340 is mounted on the functional base plate 360 ​​via a rotating shaft 350; the functional base plate 360 ​​is fixed to the motion module 100 by bolts 131.

[0050] For details, please refer to Figure 3 The functional head 340 forms a kinematic pair structure that can rotate around the axis via the rotating shaft 350, enabling rapid switching between the working positions of the laser marking unit 310 and the laser depth measurement unit 320. The functional base plate 360 ​​serves as a load-bearing substrate and is rigidly connected to the motion module 100 via bolts 131, ensuring the positioning accuracy of the functional head 340 during movement and forming a complete motion transmission chain of "motion module - functional base plate - functional head". This assembly structure achieves rapid disassembly and maintenance of the functional head 340 through modular design, while the connection between the rotating shaft 350 and the bolts 131 satisfies the mechanical requirements of both rotational motion and fixed connection, achieving flexible switching between processing and inspection functions while ensuring system rigidity.

[0051] As an example, the laser depth measurement unit 320 includes a laser confocal displacement sensor.

[0052] Specifically, the laser confocal displacement sensor, based on the confocal imaging principle, achieves absolute distance measurement by detecting the strongest reflected signal when the surface of the object being measured is at the optical focal point. The laser confocal displacement sensor possesses sub-micron level measurement accuracy, fully meeting the precision measurement requirements of the 1-20 micron depth range for marking on the wafer 410. Secondly, it is insensitive to surface tilt and reflectivity changes, overcoming measurement interference caused by material differences on the wafer 410 surface and marking marks. Furthermore, the laser confocal displacement sensor has a micron-level detection spot that can accurately fall inside the marked characters, effectively avoiding the influence of character edge contours on the measurement results. With its high precision, strong anti-interference capability, and micro-point detection characteristics, this sensor provides stable and reliable depth data for the system.

[0053] Furthermore, the motion module 100 is connected to the processing and measurement integrated module 300 via a transmission connection. The motion module 100 is responsible for driving the entire integrated module to perform precise movements in a two-dimensional plane. This allows the motion module 100 to move to any designated position on the back of the wafer 410 for marking based on the coordinates provided by the image unit, and immediately after marking is completed, the laser depth measurement unit 320 is moved to the same position for depth detection.

[0054] As an example, the motion module 100 includes an XY cross slide.

[0055] For details, please refer to Figure 2 and Figure 3The motion module 100 preferably adopts an XY cross slide as a specific implementation. This slide consists of orthogonally arranged slide rails 120 and matching sliders 130. The slide rails 120 are fixed on the base 110, and planar two-dimensional positioning is achieved by the movement of the sliders 130 on the slide rails 120. Internally, it integrates high-precision linear guides, ball screws, and a servo drive system (not labeled). Firstly, the orthogonal guide structure achieves precise positioning across the entire working plane, ensuring that the processing and measurement integrated module 300 accurately reaches each designated position. Secondly, the rigidity of the mechanical guides suppresses vibration during movement, ensuring the stability of the marking and measurement processes. Of course, the applicable motion module 100 is not limited to this and can be selected according to actual needs.

[0056] For further details, please refer to [link / reference]. Figure 1 The control system 600 is fixedly installed within the frame 200 and establishes marking signal channels 312, measurement signal channels 322, and image recognition signal channels 314 with the image recognition positioning unit 500, the laser marking unit 310, and the laser depth measurement unit 320, respectively, thereby achieving electrical connection between them. The control system 600 receives depth data from the laser depth measurement unit 320 and compares and judges it with preset process parameters in real time. If the depth is unqualified, an alarm can be triggered immediately or the marking parameters can be automatically adjusted for compensation. Ultimately, a closed-loop control of "positioning-marking-measurement-judgment-feedback" is realized, fundamentally solving the "feedback lag" problem of traditional offline detection and achieving online, real-time, and intelligent quality control.

[0057] As an example, the control system 600 includes either a programmable logic controller (PLC) or an industrial computer (IPC).

[0058] Specifically, the core of the control system 600 uses a programmable logic controller (PLC) or an industrial computer (IPC) as its control hardware. The PLC, with its defined response timing and strong anti-interference capabilities, ensures the precise coordination of the "positioning-marking-measurement" process. The IPC, with its powerful data processing capabilities, supports real-time data recording, statistical analysis, and advanced human-machine interaction functions. This design not only ensures the long-term stable operation of the equipment in industrial environments but also provides the system with scalability from basic control to intelligent data analysis, achieving an optimal balance between reliability and control complexity. Of course, the description of the PLC and IPC is intended to clarify the core architecture and does not constitute the sole limitation on the hardware selection of the control system 600. In practical applications, it can be expanded according to specific functional and performance requirements.

[0059] As an example, the control system 600 communicates with an alarm device 610, which is one of an audible alarm, a visual alarm, or an audible and visual alarm.

[0060] For details, please refer to Figure 1 The alarm device 610 in this embodiment is not limited to a specific form. In a preferred embodiment, an audible and visual alarm can be used to provide a strong warning through light and sound. Furthermore, the alarm device 610 can also be a status indicator light that only includes a visual warning, a vibration alarm that can attract tactile attention, or any combination of these forms. Its core function is to receive signals from the control system 600 and provide a perceptible warning to the operator.

[0061] This utility model discloses a laser marking and automatic inspection system, including a frame, a stage, an image recognition and positioning unit, a processing and measurement integrated module, a motion module, and a control system. The stage has a hollowed-out area in the middle; the image recognition and positioning unit is located above the stage and aligned with the hollowed-out area; the processing and measurement integrated module is located below the stage and integrates a laser marking unit and a laser depth measurement unit; the motion module is drively connected to the integrated module to drive its movement. This utility model integrates marking and measurement functions into one unit, driven by a motion module for collaborative operation, achieving fully automated closed-loop control of the entire process of marking, depth measurement, quality judgment, and feedback. It fundamentally solves the technical problems of low efficiency and delayed feedback in traditional offline inspection, significantly improving the intelligence level and product quality consistency of semiconductor wafer marking. Therefore, this utility model effectively overcomes the various shortcomings of existing technologies and has high industrial application value.

[0062] The above embodiments are merely illustrative of the principles and effects of this utility model and are not intended to limit the scope of this utility model. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this utility model. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this utility model should still be covered by the claims of this utility model.

Claims

1. A laser marking and automatic inspection system, characterized in that, include: frame; A stage, which is fixed on a frame and used to support wafers, has a hollow area in the middle that runs through the upper and lower surfaces of the stage; An image recognition and positioning unit is located above the platform, and the camera of the image recognition and positioning unit is facing the hollowed-out area. A processing and measurement integrated module is disposed below the stage, and the processing and measurement integrated module integrates a laser marking unit and a laser depth measurement unit; the marking optical path of the laser marking unit is aligned with the hollowed-out area, and the measurement optical path of the laser depth measurement unit is aligned with the hollowed-out area; A motion module, wherein the motion module is connected to the processing and measurement integrated module via a transmission connection; The control system is configured such that both the laser marking unit and the laser depth measurement unit are communicatively connected to the control system.

2. The laser marking and automatic detection system according to claim 1, characterized in that: The image recognition and positioning unit has a dome-shaped structure and a highly reflective mirror on its inner wall.

3. The laser marking and automatic detection system according to claim 1, characterized in that: The processing and measurement integrated module includes a horizontal mounting plate, on which the laser marking unit and the laser depth measurement unit are fixed side by side.

4. The laser marking and automatic detection system according to claim 1 or 3, characterized in that: A direct signal connection channel is provided between the laser marking unit and the laser depth measurement unit; the distance between the measurement optical path and the marking optical path is less than or equal to the distance between two adjacent marking positions on the platform.

5. The laser marking and automatic detection system according to claim 1, characterized in that: The processing and measurement integrated module includes a functional head, and the laser marking unit and the laser depth measurement are integrated inside the functional head; the functional head is configured to switch between the marking optical path and the measurement optical path.

6. The laser marking and automatic detection system according to claim 5, characterized in that: The functional head is mounted on the functional base plate via a rotating shaft; the functional base plate is fixed to the motion module by bolts.

7. The laser marking and automatic detection system according to claim 1, characterized in that: The motion module includes an XY cross slide.

8. The laser marking and automatic detection system according to claim 1, characterized in that: The laser depth measurement unit includes a laser confocal displacement sensor.

9. The laser marking and automatic detection system according to claim 1, characterized in that: The control system includes either a programmable logic controller (PLC) or an industrial computer (IPC).

10. The laser marking and automatic detection system according to claim 1, characterized in that: The control system communicates with an alarm device, which includes one of an audible alarm, a visual alarm, or an audible and visual alarm.

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