System and method for micro-led mass transfer chip positioning and flight observation

Abstract

The application belongs to the technical field of micro device assembly, and discloses a system and a method for positioning and flight observation of a MicroLED mass transfer chip, the system comprising: a binocular vision assembly, including a first monocular vision channel and a second monocular vision channel, the first monocular vision channel including a high-power lens and a high-resolution camera; the second monocular vision channel adopting a low-power lens and a low-resolution camera, the lens collection area of the binocular vision assembly being a flight observation area of the chip; an excitation, used for triggering the falling transfer process of the chip; a digital delay pulse generator, including multiple channels, the trigger time and the delay time of each channel being controlled individually, the excitation, the first monocular vision unit and the second monocular vision unit being connected with a channel respectively, and different delay trigger signals being set to realize accurate capture of the chip falling time state. The application can realize accurate and rapid positioning of the chip and local and global observation of the flight state of the chip.

Description

Technical Field

[0001] This invention belongs to the technical field of microdevice assembly, and more specifically, relates to a system and observation method for positioning and flying observation of MicroLED mass transfer chips. Background Technology

[0002] With the development of the semiconductor industry, the integration of electronic components is becoming increasingly higher, and their feature sizes are becoming smaller. This places increasingly higher demands on assembly precision during manipulation. This presents a significant challenge to the field of microdevice assembly, which mainly involves two steps: pick-up and release. Depending on whether the microdevice contacts the receiving substrate during release, existing assembly methods are mainly categorized as contact-based and non-contact-based. Regardless of the method, the assembly device needs to be positioned and aligned with the microdevice during both pick-up and release to meet assembly precision and process reliability requirements. Using vision cameras for assisted positioning is a common method in the industry. However, due to limitations in lens processing, the larger the field of view of a lens, the lower its optical precision. For chips on a wafer, which are very small but numerous, it is difficult to simultaneously meet the requirements of a large field of view and high precision using a single vision component. How to quickly locate the target chip on the wafer and simultaneously observe its features to achieve precise positioning and monitor the chip's flight status remains a persistent challenge for the industry. Summary of the Invention

[0003] To address the aforementioned deficiencies or improvement needs of existing technologies, this invention provides a system and method for locating and observing MicroLED mass transfer chips in flight. It enables precise chip positioning and local and global observation of the chip's flight status.

[0004] To achieve the above objectives, according to one aspect of the present invention, a system for positioning and flight observation of a MicroLED mass transfer chip is provided. The system includes: a binocular vision component, comprising a first monocular vision channel and a second monocular vision channel, wherein the first monocular vision channel includes a high-magnification lens and a high-resolution camera; the second monocular vision channel employs a low-magnification lens and a low-resolution camera. During positioning, the lens acquisition area of ​​the binocular vision component is the target chip area; during flight observation, the lens acquisition area of ​​the binocular vision component is the flight observation area of ​​the chip; an excitation device for triggering the chip's drop transfer process; and a digital delay pulse generator, comprising multiple channels, wherein the trigger time and delay time of each channel are individually controlled, and the excitation device, the first monocular vision unit, and the second monocular vision unit are respectively connected to one of the channels.

[0005] Preferably, the system further includes a backlight source connected to an independent channel of the digital delay pulse generator, so that the digital delay pulse generator controls the trigger time and delay time of the backlight source.

[0006] Preferably, the system further includes a display window connected to the binocular vision component for visually displaying the images acquired by the first monocular vision unit and the second monocular vision unit.

[0007] Preferably, the binocular vision assembly further includes a binocular connection module, a first semi-transparent and semi-reflective mirror, a second semi-transparent and semi-reflective mirror, and a total reflection mirror. The binocular connection module has a hollow structure, with both ends sealed and two holes on its vertical surface, namely a first hole and a second hole. The first hole penetrates the lower and upper surfaces of the binocular connection module and is used to connect to one end of the high-magnification lens. The second hole penetrates the upper surface of the binocular connection module and is used to connect to one end of the low-magnification lens. The first semi-transparent and semi-reflective mirror is disposed at a 45° angle in the first hole, the second semi-transparent and semi-reflective mirror is disposed at a 135° angle in the high-magnification lens, and the total reflection mirror is disposed at a 45° angle in the second hole.

[0008] Preferably, the surface of the high-magnification lens is provided with a light-transmitting hole, the axis of which is aligned with the center of the light-receiving surface of the second semi-transparent mirror, and the light-transmitting hole is used to receive light from a coaxial light source.

[0009] Preferably, the display window includes a first display window and a second display window for displaying photos captured by the high-resolution camera and the low-resolution camera, respectively.

[0010] According to another aspect of the present invention, an observation method for the above-mentioned MicroLED mass transfer chip positioning and flight observation system is provided, the method comprising: S1: obtaining fuzzy positioning of the target chip through the second display window, and obtaining precise positioning of the target chip through the first display window; S2: using the digital delay pulse generator to trigger the excitation to match the response time of the chip falling; S3: after triggering the excitation, using the digital delay pulse generator to synchronously trigger the backlight source and the binocular vision component, thereby setting multiple trigger signals to obtain the flight status of the chip at different altitudes.

[0011] Overall, compared with the prior art, the system and method for positioning and flying observation of MicroLED mass transfer chips provided by this invention offer the following advantages:

[0012] 1. The binocular vision component of this application includes a first monocular vision channel and a second monocular vision channel, which are used for local fine observation and global observation, respectively. This solves the contradiction between the large field of view and high precision of the camera in the current observation scheme. During positioning observation, it can not only observe the position of the target in the global context and quickly find the target, but also achieve high-precision alignment.

[0013] 2. High-speed dynamic observation of objects at the micrometer scale can be achieved using binocular vision cameras and excitation devices. When the target moves at high speeds, high-speed cameras are often required to capture images by increasing the frame rate, which is expensive. This invention controls the imaging of a conventional industrial camera by controlling the flash frequency of the light source, and simultaneously uses a digital delay pulse generator to trigger different signals to achieve full-attitude trajectory imaging during flight.

[0014] 3. Its flight trajectory can be obtained through low-magnification imaging, while its flight attitude at different times can be obtained through high-magnification imaging.

[0015] 4. It can be paired with different camera lens combinations, making it highly versatile for targets of varying sizes. Furthermore, this method can be applied to various machine tools, platforms, and other processing equipment, demonstrating significant practical value.

[0016] 5. The brightness of the captured image can be adjusted through the light-transmitting aperture, the first semi-transparent mirror, and the second semi-transparent mirror. The light-transmitting aperture is located on the surface of the high-magnification lens, making it easy to set up and operate without hindering the operation of other equipment. Attached Figure Description

[0017] Figure 1 This is a schematic diagram illustrating the observation principle of the chip's flight and descent process.

[0018] Figure 2 It is the excitation response mode diagram during the assembly of micro-pitch chips;

[0019] Figure 3 This is a schematic diagram of the alignment of multi-target coaxial positioning observation using a binocular vision module;

[0020] Figure 4 This describes the principle and optical path diagram of multi-target coaxial positioning observation using binocular vision components.

[0021] Figure 5 This is a state diagram of the binocular vision component when it is used for chip flight observation;

[0022] Figure 6 It is a schematic diagram of the control of backlight source, camera, and excitation.

[0023] In all the accompanying drawings, the same reference numerals are used to denote the same elements or structures, wherein:

[0024] 10-First monocular vision unit; 11-Second monocular vision unit; 100-High-resolution camera; 101-Low-resolution camera; 102-High-magnification lens; 103-Low-magnification lens; 104-Dual-view connection module; 105-Light passage; 106-Second semi-transparent mirror; 107-First semi-transparent mirror; 108-Total internal reflection mirror; 200-Substrate; 201-Chip; 300-First display window; 301-Second display window; 302-Chip imaging under high magnification; 303-Chip imaging under low magnification; 304-Data connection line; 400-Coaxial light source; 401-Backlight source; 500-Digital delayed pulse generator; 501-Channel; 60-Tool; 600-Excitation. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0026] This invention provides a system for positioning and flight observation of MicroLED mass transfer chips, such as... Figure 1 and Figure 2 As shown, the system includes a binocular vision component, an excitation unit 600, a digital delay pulse generator 500, etc.

[0027] like Figure 3 and Figure 4 As shown, the binocular vision component includes a first monocular vision unit 10 and a second monocular vision unit 11. The first monocular vision unit 10 includes a high-magnification lens 102 and a high-resolution camera 100. The second monocular vision unit 11 uses a low-magnification lens 103 and a low-resolution camera 101. The lens acquisition area of ​​the binocular vision component is the flight observation area of ​​the chip.

[0028] The binocular vision assembly further includes a binocular vision connection module 104, a first semi-transparent and semi-reflective mirror 107, a second semi-transparent and semi-reflective mirror 106, and a total reflection mirror 108. The binocular vision connection module 104 has a hollow structure, with both ends sealed and two holes on its vertical surface, namely a first hole and a second hole. The first hole penetrates the lower and upper surfaces of the binocular vision connection module 104 and is used to connect to one end of the high-magnification lens. The second hole penetrates the upper surface of the binocular vision connection module 104 and is used to connect to one end of the low-magnification lens 103. The first semi-transparent and semi-reflective mirror 107 is disposed at a 45° angle in the first hole, the second semi-transparent and semi-reflective mirror 106 is disposed at a 135° angle in the high-magnification lens 102, and the total reflection mirror 108 is disposed at a 45° angle in the second hole.

[0029] The binocular vision component can also be used for precise positioning. In this case, the surface of the high-magnification lens 102 is provided with a light-transmitting hole 105. The axis of the light-transmitting hole 105 is aligned with the center of the light-receiving surface of the second semi-transparent mirror 106. The light-transmitting hole is used to receive the illumination of the coaxial light source 400. Local fine observation can be achieved through the first monocular vision channel, and global observation can be achieved through the second monocular vision channel, thus achieving fast and high-precision alignment and positioning.

[0030] Excitation 600 is used to trigger the chip 201 to fall and transfer from the substrate 200.

[0031] The digital delay pulse generator 500 includes multiple channels 501, each channel 501 having its trigger time and delay time controlled independently. The excitation 600, the first monocular vision unit 10, and the second monocular vision unit 11 are each connected to one of the channels 501.

[0032] The system also includes a backlight source 401, which is connected to an independent channel of the digital delay pulse generator 500 so that the digital delay pulse generator 500 controls the trigger time and delay time of the backlight source 401.

[0033] The system also includes a display window connected to the binocular vision component for visually displaying images acquired by the first and second monocular vision units. The display window includes a first display window 300 and a second display window 301 connected to a high-resolution camera 100 and a low-resolution camera 101 respectively via a data connection cable 304, for displaying photographs acquired by the high-resolution and low-resolution cameras. The images from the first and second monocular vision units are displayed on two monitors or in two windows on one monitor. The first monocular vision unit, due to its higher magnification, can observe only one chip or local features of a chip in the displayed image, generating a high-magnification chip image 302. The second monocular vision unit, due to its lower magnification, has a wider field of view in the displayed image, enabling the observation of more chips and the location of the target chip within the global field of view, generating a low-magnification chip image 303.

[0034] During operation, when the coaxial light source is turned on, the light from the coaxial light source is reflected by the first semi-transparent mirror and then partially reaches the second semi-transparent mirror. The other part is absorbed or scattered by the inner wall of the high-magnification lens. The light reaching the second semi-transparent mirror is split into two parts: one part is transmitted and illuminates the target object, while the other part is reflected and absorbed or scattered by the inner wall of the binocular vision module. The light reaching the target object is reflected again and reaches the second semi-transparent mirror. Similarly, a portion of the light is reflected and reaches the total internal reflection mirror, while the other part is transmitted and reaches the first semi-transparent mirror. The light reaching the total internal reflection mirror is reflected and enters the camera in the second monocular vision unit to form an image. The light reaching the first semi-transparent mirror is again split into two parts: one part is reflected and leaves the binocular vision module, while the other part is transmitted and enters the camera in the first monocular vision unit to form an image.

[0035] By selecting different camera lenses, it is possible to achieve not only high-precision observation with a small field of view to address local features of micron-scale targets, but also low-precision observation with a large field of view to determine the target's location within the global field of view. Chip descent and flight observation utilizes the aforementioned binocular vision components, combined with a backlight or coaxial light source, to observe the descent and flight state of the chip (micro-component) during assembly. The observation method involves using a digital pulse generator to delay the light source, binocular vision components, and drive excitation, allowing the camera to capture the chip's flight state and enabling observation of the high-speed motion of micron-scale targets.

[0036] The following preparations need to be made before image acquisition:

[0037] Step 1: Calibrate the relative position of the cutting tool 60 (which can also be a laser, nozzle, ejector pin, or other device for processing the target object; for ease of description, it will be collectively referred to as the cutting tool) and the binocular vision assembly, and record it as Δd. Recalibration is not required if the cutting tool is not changed or the position of the binocular vision assembly is not altered.

[0038] Step 2: Mount the target on the motion platform and move it below the lens of the binocular vision unit. Turn on the light source and ensure the camera's power supply and data connection are normal. Then open the corresponding software for the camera.

[0039] Step 3: Adjust the distance between the target object and the binocular vision components, and adjust the focal length, such as... Figure 5 As shown, the binocular vision component can be rotated 90 degrees so that the target is within the range of the lens, resulting in a clear image on the computer screen.

[0040] Step 4: Move the motion platform to locate the target in the second display window and initially align it with the crosshair cursor in the window. At this point, the target image will appear in the first display window. Adjust the target position again so that the target image in the first display window is aligned with the crosshair cursor. Record the position of the motion platform; at this point, the target position is aligned with the binocular vision components. Record the coordinates of the motion platform at this time.

[0041] Step 5: Based on the relative position Δd, move the motion platform below the tool. At this point, the target object and the tool are aligned.

[0042] Step 6: Begin processing or other operations.

[0043] like Figure 6 As shown, after adjusting the above positions, the following method is used to observe the chip falling process:

[0044] S1: Obtain the fuzzy positioning of the target chip through the second display window, and obtain the precise positioning of the target chip through the first display window;

[0045] S2: The digital delay pulse generator is used to trigger the excitation to match the response time of the chip falling;

[0046] S3: After triggering the excitation, the digital delay pulse generator synchronously triggers the backlight source and the binocular vision component. Multiple trigger signals are set in this way to obtain the chip's flight state at different altitudes. At this time, the flash frequency of the backlight source and the imaging frequency of the binocular vision component are the same. This allows for the capture of partial images of the chip's falling process. Finally, by continuously adjusting the delay time and conducting the same set of experiments, the chip's attitude and trajectory during its descent can be obtained.

[0047] If the distance between the chip and the receiving substrate is too small to realize the flight and descent process, a high-magnification microscope can be used to observe the transfer state under re-excitation.

[0048] When the distance between the chip and the receiving substrate is small, the chip makes micro-contact with the substrate during assembly and does not have a flight attitude. By focusing the binocular vision component on the transfer stamp, the bubble size, bubble speed, and chip tilt attitude can be observed.

[0049] In summary, this application provides a system and method for locating and observing MicroLED mass transfer chips in flight. It enables precise chip positioning and local and global observation of the chip's flight status.

[0050] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A system for MicroLED mass transfer chip positioning and flight observation, characterized in that, The system comprises: A binocular vision assembly comprising a first monocular vision channel and a second monocular vision channel, the first monocular vision channel comprising a high-power lens and a high-resolution camera; the second monocular vision channel comprising a low-power lens and a low-resolution camera, the lens collection area of the binocular vision assembly being the target chip area during positioning, and the lens collection area of the binocular vision assembly being the flight observation area of the chip during flight observation; An excitation for triggering the falling transfer process of the chip; A digital delay pulse generator comprising a plurality of channels, the trigger time and delay time of each channel being controlled individually, the excitation, the first monocular vision unit and the second monocular vision unit being connected to a channel of the digital delay pulse generator respectively; The system further comprises a backlight light source connected to an independent channel of the digital delay pulse generator, so that the digital delay pulse generator controls the trigger time and delay time of the backlight light source; The observation method for chip falling flight observation is to use the digital delay pulse generator to delay and distribute the light source, the binocular vision assembly and the driving excitation, so that the camera captures the flight state of the chip, and the high-speed motion state of the micron-scale target is observed.

2. The system of claim 1, wherein, The system further comprises a display window connected to the binocular vision assembly for visual display of the images collected by the first monocular vision unit and the second monocular vision unit.

3. The system of claim 1, wherein, The binocular vision assembly further comprises a double-vision connection module, a first semi-transparent semi-reflective lens, a second semi-transparent semi-reflective lens and a full-reflective lens, the double-vision connection module being a hollow structure, the two ends of the double-vision connection module being sealed and the vertical surface thereof being provided with two holes, i.e. a first hole and a second hole, wherein the first hole penetrates the lower and upper surfaces of the double-vision connection module and is used for connecting one end of the high-power lens, and the second hole penetrates the upper surface of the double-vision connection module and is used for connecting one end of the low-power lens, the first semi-transparent semi-reflective lens being arranged in the first hole at an angle of 45°, the second semi-transparent semi-reflective lens being arranged in the high-power lens at an angle of 135°, and the full-reflective lens being arranged in the second hole at an angle of 45°.

4. The system of claim 3, wherein, The surface of the high-power lens is provided with a light transmission hole, the axis of the light transmission hole being aligned with the center of the light receiving surface of the second semi-transparent semi-reflective lens, and the light transmission hole being used for receiving light from a coaxial light source.

5. The system of claim 2, wherein, The display window comprises a first display window and a second display window for displaying the photos collected by the high-resolution camera and the low-resolution camera respectively.

6. A method for observing the system for positioning and flight observation of the MicroLED mass transfer chip according to any one of claims 1-5, characterized in that, The system further comprises a display window connected to the binocular vision assembly for visual display of the images collected by the first monocular vision unit and the second monocular vision unit; The display window comprises a first display window and a second display window for displaying the photos collected by the high-resolution camera and the low-resolution camera respectively; the method comprises: S1: obtaining a fuzzy positioning of the target chip through the second display window and a precise positioning of the target chip through the first display window; S2: triggering the excitation matching the response time of the chip falling by using the digital delay pulse generator. S3: after triggering the excitation, the digital delay pulse generator is used to synchronously trigger the backlight light source and binocular vision components, in this way, a plurality of trigger signals are set to obtain the flight state of the chip at different heights.

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