Optical lever detection device and detection method of Micro Led chip

Abstract

The invention relates to the field of chip bonding quality detection, in particular to an optical lever detection device and method for a Micro Led chip, comprising a sample displacement table, a force deformation part, an optical module and a detection module, the sample displacement table is used for transferring a to-be-detected chip to a target detection position, and the force deformation part comprises a clamping part, a cantilever and a probe part; the optical module comprises a supporting piece, a clamp, a reflecting prism, a diaphragm assembly and a laser source. According to the optical lever detection device of the Micro Led chip, the laser source emits the laser beam to the reflecting prism through the diaphragm assembly, the laser beam is reflected to the surface of the probe part by the reflecting prism, and the angle information of the light reflected by the surface of the probe part is identified and received by the detector, so that when the deformation amounts of the probe part abutting against the chip to be detected are different, the chip to be detected can be detected; the cantilever or the probe part deforms, the angle of the surface reflection light changes, and then the detector detects the contact force between the chip to be detected and the probe part according to the angle change of the reflection light.

Description

Technical Field

[0001] The present invention relates to the technical field of chip bonding quality detection, and in particular to an optical lever detection device and a detection method for a Micro LED chip. Background Art

[0002] With the advancement of LED display technology, LED chip sizes and pixel pitches are gradually moving toward micro- and nanoscales, making large-scale panel splicing more flexible, interactive, and easier to manufacture in modular form. Panel-level MicroLed displays offer advantages such as high brightness, high contrast, low power consumption, fast response time, and excellent color rendering, and are becoming a key development direction for next-generation display technologies.

[0003] In the prior art, a Micro Led chip connection adhesion detection device and detection method with application number CN202410621892.0 is disclosed, which includes a carrying and transferring mechanism, which is used to load the chip to be detected and move the chip to be detected to the target detection position; a force deformation detection mechanism, which includes a detection probe, a deformation module and a detection module, wherein the detection probe is arranged on one side of the carrying and transferring mechanism and is used to interfere with the chip to be detected, the deformation module is connected to the detection probe, and can sense the contact force of the detection probe and generate an adaptive deformation, the detection module is assembled with the deformation module and is used to convert the deformation of the deformation module into a displacement; and a data analysis device, which is electrically connected to the detection module and is used to convert the displacement obtained by the detection module into an electrical signal, thereby calculating the real-time detection connection adhesion size. However, when the deformation module is used to convert the data into displacement, the structural redundancy is large and the accuracy of the chip adhesion measurement results is not accurate enough, resulting in the inability to distinguish between the excellent, good, and qualified grades of the chip-to-substrate connection.

[0004] Therefore, on the basis of solving the bonding force measurement between Micro Led chips and substrates, it is necessary to further simplify the structural design and improve the accuracy of the bonding force measurement results between chips and substrates, so as to distinguish the excellent, good and qualified grades of the chip and substrate connections, and thus better solve the problems of uneven brightness, color deviation, pixel failure, inconsistent response time and unstable service life of Micro Led display panels. Summary of the Invention

[0005] The first object of the present invention is to provide an optical lever detection device for a Micro Led chip, aiming to solve the problem of low accuracy in measuring the bonding force between the Micro Led chip and the substrate.

[0006] To solve the above technical problems, a light lever detection device for a Micro Led chip is provided, which includes a sample displacement stage, a force deformation member, an optical module, and a detection module. The sample displacement stage is used to load the chip to be detected and move the chip to be detected to the target detection position. The force deformation member includes a clamping portion, a cantilever, and a probe head. The two ends of the cantilever are respectively connected to the clamping portion and the probe head, and the probe head abuts against the chip to be detected. The optical module includes a support member, a fixture, a reflection prism, an aperture assembly, and a laser source. The fixture is connected to one end of the support member for connecting the clamping portion. The reflection prism slides on the support member and is located above the clamping portion. The laser source is located at a position of the support member far from the reflection prism, and the aperture assembly is located between the laser source and the reflection prism. The detection module includes a monitoring camera and a detector. The monitoring camera is located above the probe head for identifying the relative position between the force deformation member and the chip to be detected, and the detector is located in the obliquely upward direction of the probe head. Wherein, the chip to be detected is connected to the substrate to generate a bonding force. The laser source emits a laser beam through the aperture assembly to the reflection prism, and the laser beam is reflected by the reflection prism to the surface of the probe head. The angle information of the light reflected by the surface of the probe head is identified and received by the detector. When the deformation amount of the probe head abutting against the chip to be detected is different, the angle of the light reflected by the surface of the probe head changes to detect the magnitude of the contact force between the chip to be detected and the probe head.

[0007] Further, the contact force between the probe head and the chip to be detected is denoted as F, the flexural rotation angle between the cantilever and the clamping portion is denoted as a, and the flexural rotation angle a is positively correlated with the contact force F.

[0008] Further, the bonding force between the chip to be detected and the substrate is denoted as f, the point where the laser beam hits the probe head is the light spot, the side surface where the probe head contacts the chip to be detected is the contact surface, the horizontal distance from the light spot to the contact surface is l, and the horizontal distance from the contact surface to the cantilever is L. When 0 < F ≤ 1 / 2f, l = 2 / 3L; when 1 / 2f < F ≤ f, l = 1 / 3L.

[0009] Further, the probe head is obliquely downward connected to the end of the cantilever. The flexural rotation angle between the cantilever and the probe head is denoted as b. When 1 / 2f < F ≤ f, the flexural rotation angle b is positively correlated with the bonding force f.

[0010] Furthermore, the support member includes a limiting groove, a light guide groove and a notch groove, the limiting groove is located at the end of the support member, the light guide groove connects the laser source and the limiting groove, the reflecting prism slides on the limiting groove, the notch groove is connected to the bottom of the limiting groove, the clamp fixes the clamping part on one side of the limiting groove, and the notch groove is opposite to the probe part, so that the laser beam emitted by the laser source passes through the light guide groove, the limiting groove and the notch groove to the probe part respectively.

[0011] Furthermore, the optical module also includes a first fastener and a second fastener, the first fastener is connected to the reflective prism parallel to the direction of the light guide groove, and the second fastener abuts against the reflective prism perpendicular to the direction of the light guide groove, so that the reflective prism can adjust its relative position with the limit groove.

[0012] Furthermore, the aperture assembly includes a first aperture piece and a second aperture piece, and the first aperture piece and the second aperture piece are spaced apart and located on the light guide groove.

[0013] Furthermore, the optical lever detection device of the Micro Led chip further includes a digital terminal, and the digital terminal is electrically connected to the monitoring camera and the detector respectively.

[0014] The second object of the present invention is to provide an optical lever detection method for a Micro Led chip, aiming to solve the problem of low accuracy in measuring the bonding force between the Micro Led chip and the substrate.

[0015] In order to solve the above technical problems, a method for detecting an optical lever of a Micro Led chip is provided, which is applicable to the optical lever detection device of the above Micro Led chip, comprising the following steps: S1. Input the bonding force level between the chip to be tested and the substrate; S2. Mounting the chip to be detected on the sample displacement stage, controlling the sample displacement stage to move the chip to be detected to a target detection position so that the probe portion contacts the chip to be detected; S3, the sample displacement stage continues to drive the chip to be tested to move toward the probe part, so that the probe part generates an extrusion force, and the extrusion force forces the force deformation member to generate a deformation amount; S4, the detection module detects the deformation of the force-deformable member and converts it into an angular displacement of the laser beam; S5. The monitoring camera and the detector transmit the displacement of the laser beam to a digital terminal. The digital terminal converts the angular displacement of the laser beam into an electrical signal and calculates the real-time contact force of the force-deformation member. When the real-time contact force of the force-deformation member reaches the theoretical critical connection force between the chip to be tested and the substrate, the sample displacement stage is controlled to stop moving, and the status of the chip to be tested is identified and determined by the monitoring camera.

[0016] Furthermore, the contact force of the real-time force deformation member reaches the theoretical critical connection force between the chip to be detected and the substrate, including the following steps: When the theoretical critical connection force is much greater than the real-time contact force of the force deformation part, the reflective prism is adjusted to move away from the probe part; when the real-time contact force of the force deformation part gradually approaches the theoretical critical connection force from small to large, the reflective prism is adjusted to move toward the probe part.

[0017] The implementation of the present invention will have the following beneficial effects: In the optical lever detection device for Micro LED chips in this embodiment, since the chip to be detected is connected to the substrate to generate a bonding force, a laser source emits a laser beam through the aperture assembly to the reflective prism. The laser beam is reflected by the reflective prism to the surface of the probe part. The angle information of the light reflected from the surface of the probe part is recognized and received by the detector. Therefore, when the deformation amount of the probe part abuts against the chip to be detected is different, the cantilever or the probe part is deformed, and the angle of the light reflected from the surface changes. Then, the detector detects the contact force between the chip to be detected and the probe part based on the change in the angle of the reflected light, thereby overcoming the problem of low accuracy in the bond force measurement of Micro LED chips and substrates in the prior art.

[0018] In the optical lever detection device for the Micro Led chip in this embodiment, the support member includes a limit groove, a light guide groove, and a notch groove. The limit groove is located at the end of the support member, the light guide groove connects the laser source and the limit groove, the reflective prism slides on the limit groove, and the notch groove is connected to the bottom of the limit groove. The clamp fixes the clamping part to one side of the limit groove, and the notch groove faces the probe part. Therefore, by adjusting the position of the reflective prism in the limit groove, the position of the laser reflected to the probe part is forced to change, and the angle of the laser reflected by the probe part changes according to the deformation of the cantilever or the probe part.

[0019] In the optical lever detection method for Micro LED chips in this embodiment, the chip to be detected is mounted on a sample displacement stage. The displacement stage drives the chip to be detected to the target detection position so that the probe portion contacts the chip to be detected. The sample displacement stage then continues to drive the chip to be detected toward the probe portion, generating a squeezing force between the probe portion and the chip to be detected. This squeezing force forces the force-deforming element to deform. The detection module detects the deformation of the force-deforming element and converts it into the angular displacement of the laser beam. The monitoring camera and detector then transmit the displacement of the laser beam to the digital terminal, which converts the angular displacement of the laser beam into an electrical signal and calculates the real-time contact force of the force-deforming element. When the real-time contact force of the force-deforming element reaches the theoretical critical connection force between the chip to be detected and the substrate, the sample displacement stage is controlled to stop moving, and the monitoring camera is used to identify and determine the status of the chip to be detected. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0021] Figure 1 This is a schematic diagram of the optical lever detection device for the Micro Led chip according to the first embodiment of the present invention; Figure 2 Schematic diagram of the principle of the optical lever detection device of the Micro Led chip according to the first embodiment of the present invention Figure 3 This is a schematic structural diagram of an optical module according to Embodiment 1 of the present invention; Figure 4 This is an exploded schematic diagram of the optical module according to the first embodiment of the present invention; Figure 5 This is a schematic structural diagram of a support member according to Embodiment 1 of the present invention; Figure 6 This is a schematic structural diagram of the force-deformation member according to the first embodiment of the present invention; Figure 7 for Figure 6 A partial enlarged view of point A in the middle; Figure 8 This is a flow chart of the optical lever detection method for a Micro Led chip according to the second embodiment of the present invention.

[0022] Among them: 100, optical lever detection device; 110, sample displacement stage; 120, chip to be detected; 121, substrate; 130, force deformation member; 131, clamping part; 132, cantilever; 133, probe part; 140, optical module; 141, support member; 1411, limit groove; 1412, light guide groove; 1413, notch groove; 142, fixture; 143, reflecting prism; 144, aperture assembly; 1441, first aperture piece; 1442, second aperture piece; 145, laser source; 146, first fastener; 147, second fastener; 150, detection module; 151, monitoring camera; 152, detector; 160, digital terminal. DETAILED DESCRIPTION

[0023] To facilitate understanding of the present invention, the present invention will be described more fully below with reference to the accompanying drawings. Preferred embodiments of the present invention are shown in the accompanying drawings. However, the present invention may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the present disclosure.

[0024] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly attached to the other element or there may be an intermediate element. When an element is referred to as being "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one skilled in the art to which this invention pertains. The terms used in this specification of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items. Example

[0026] Please refer to Figure 1-Figure 7The first embodiment of the present invention provides an optical lever detection device 100 for a Micro LED chip, comprising a sample displacement stage 110, a force deformation member 130, an optical module 140, and a detection module 150. The sample displacement stage 110 is used to load a chip to be detected 120 and move the chip to be detected 120 to a target detection position. The force deformation member 130 comprises a clamping portion 131, a cantilever 132, and a probe portion 133. The two ends of the cantilever 132 are respectively connected to the clamping portion 131 and the probe portion 133, and the probe portion 133 abuts against the chip to be detected 120. The optical module 140 comprises a support 141, a fixture 142, a reflecting prism 143, an aperture assembly 144, and a laser. Light source 145, fixture 142 connected to one end of support member 141 for connection to clamping portion 131, reflecting prism 143 slides on support member 141 and is located above clamping portion 131, laser source 145 is located on support member 141 away from reflecting prism 143, and aperture assembly 144 is located between laser source 145 and reflecting prism 143; detection module 150 includes monitoring camera 151 and detector 152. Monitoring camera 151 is located above probe portion 133 for identifying the relative position of force-deformable member 130 and chip to be detected 120, and detector 152 is located diagonally upward from probe portion 133. The chip to be tested 120 is connected to the substrate 121 to generate bonding force. The laser source 145 emits a laser beam through the aperture assembly 144 to the reflective prism 143. The laser beam is reflected by the reflective prism 143 to the surface of the probe part 133. The angle information of the light reflected from the surface of the probe part 133 is recognized and received by the detector 152. When the deformation amount of the probe part 133 is different when it abuts against the chip to be tested 120, the angle of the light reflected from the surface of the probe part 133 changes to detect the contact force between the chip to be tested 120 and the probe part 133. In specific applications, Micro When the optical lever detection device 100 for LED chips is used, the bonding force between the chip to be detected 120 and the substrate 121 is first determined; the chip to be detected 120 is mounted on the sample displacement stage 110, and the sample displacement stage 110 is controlled to drive the chip to be detected 120 to move to the target detection position so that the chip to be detected 120 contacts the probe part 133; the sample displacement stage 110 continues to drive the chip to be detected 120 toward the probe part 133, so that a squeezing force is generated between the two. The squeezing force forces the deformation member 130 to deform, thereby generating an angular deflection of the probe part 133. The reflection angle of the laser beam when it hits the surface of the probe part 133 changes, and the angle information of the light reflected from the surface of the probe part 133 is recognized and received by the detector 152. The force-deforming member 130 then converts the deformation into an angular deflection of the laser beam. The contact force of the force-deforming member 130 can be calculated based on the deformation of the force-deforming member 130. By comparing the contact force of the force-deforming member 130 with the theoretical critical connection force between the chip to be detected 120 and the substrate 121 (the critical connection force is the maximum external force required to separate the chip to be detected 120 and the substrate 121 when the two have a complete welding area and optimal welding strength. In this embodiment, the external force can be the squeezing force between the chip to be detected 120 and the force-deforming member 130), the welding strength between the electrode of the chip to be detected 120 and the pad on the substrate 121 can be distinguished as excellent, good, or qualified, thereby reducing the probability of problems such as uneven brightness, color deviation, pixel failure, and inconsistent response time in the Micro Led display, ensuring the overall display quality and performance, and improving the yield rate of the Micro Led display.

[0027] It is worth noting that the chip to be tested 120 in the present invention can be a single chip or a chip array unit composed of multiple chips. When the chip to be tested 120 refers to a chip array unit, the connection force test needs to be performed on each chip to be tested 120 in sequence during testing. In this case, there is a gap between two adjacent chips to be tested 120. The size of this gap should be sufficient to accommodate the probe portion 133 so that the probe portion 133 can contact the side of the chip to be tested 120.

[0028] It can be understood that the sample displacement stage 110 is specifically composed of an X-axis movement module, a Y-axis movement module, and a Z-axis movement module, which can respectively or synchronously drive the substrate 121 to move linearly with high precision in the positive and negative directions of the X-axis, Y-axis, and Z-axis, so as to ensure that the probe head 133 can accurately move to each gap and effectively contact different chips 120 to be detected. The sample displacement stage 110 is used to fix the substrate 121, thereby preventing the substrate 121 and the chips 120 to be detected mounted thereon from moving or rotating in the XY-axis direction due to the contact force of the probe head 133 during the test, which may affect the test results.

[0029] In a possible implementation manner, denote the contact force between the probe head 133 and the chip 120 to be detected as F, and the deflection angle between the cantilever 132 and the clamping part 131 as α. The deflection angle α is positively correlated with the contact force F. In specific applications, the sample displacement stage 110 continues to drive the chip 120 to be detected towards the probe head 133 to generate a squeezing force therebetween. The squeezing force forces the force deformation member 130 to generate a deformation amount, and thus the probe head 133 generates an angular deflection amount. In this process, since the force deformation member 130 includes a clamping part 131, a cantilever 132, and a probe head 133, the two ends of the cantilever 132 are respectively connected to the clamping part 131 and the probe head 133, and the probe head 133 abuts against the chip 120 to be detected. Therefore, the squeezing force generated between the probe head 133 and the chip 120 to be detected will force the cantilever 132 and the clamping part 131 to form a deflection angle α, that is, the contact force F between the probe head 133 and the chip 120 to be detected is the squeezing force, and the deflection angle α increases as the contact force F increases.

[0030] In a possible implementation manner, denote the bonding force between the chip 120 to be detected and the substrate 121 as f, the point where the laser beam hits the probe head 133 as the light spot, the side surface of the probe head 133 contacting the chip 120 to be detected as the contact surface, the horizontal distance from the light spot to the contact surface as l, and the horizontal distance from the contact surface to the cantilever 132 as L. When 0 < F ≤ 1 / 2f, l = 2 / 3L; when 1 / 2f < F ≤ f, l = 1 / 3L. In specific applications, the bonding force between the chip 120 to be detected and the substrate 121 is f. During the detection process, the sample displacement stage 110 slowly drives the chip 120 to be detected towards the probe head 133. In practice, the connection strength between the chip and the substrate 121 is uneven in quality. In order to distinguish the quality of the connection strength between the chip and the substrate 121 and improve the detection accuracy, when 0 < F ≤ 1 / 2f, l = 2 / 3L, that is, the contact force between the probe head 133 and the chip 120 to be detected is small. At this time, the deformation amount of the force deformation member 130 is mainly concentrated between the clamping part 131 and the cantilever 132. The laser beam should be focused on the side of the probe head 133 close to the cantilever 132. In this way, the connection strength between the chip 120 to be detected and the substrate 121 can be effectively identified in batches during the continuous increase of the contact force F.

[0031] In a possible implementation, the probe head 133 is inclined downward and connected to the end of the cantilever 132. Denote the flexure angle between the cantilever 132 and the probe head 133 as b. When 1 / 2f < F ≤ f, the flexure angle b is positively correlated with the bonding force f. In a specific application, when the contact force F gradually increases to approach f, since the flexural deformation between the clamping portion 131 and the cantilever 132 is limited, the calculation when the contact force F is relatively large cannot be accurately recognized. That is, as the contact force F continuously increases, the flexural deformation between the clamping portion 131 and the cantilever 132 basically remains unchanged, resulting in inaccurate recognition of the strong bonding force between the identification chip and the substrate 121. Therefore, when 1 / 2f < F ≤ f, l = 1 / 3L, there is a flexure angle b between the cantilever 132 and the probe head 133, and the flexure angle b is positively correlated with the bonding force f. At this time, the deformation amount of the force deformation member 130 is not only concentrated between the clamping portion 131 and the cantilever 132, but also distributed between the cantilever 132 and the probe head 133. The laser beam should fall on the side of the probe head 133 far from the cantilever 132. In this way, a relatively large bonding force between the to-be-detected chip 120 and the substrate 121 can be effectively recognized.

[0032] In a possible implementation, the support member 141 includes a limit groove 1411, a light guide groove 1412, and a notch groove 1413. The limit groove 1411 is located at the end of the support member 141. The light guide groove 1412 connects the laser source 145 and the limit groove 1411. The reflecting prism 143 slides on the limit groove 1411. The notch groove 1413 is connected below the limit groove 1411. The fixture 142 fixes the clamping portion 131 to one side of the limit groove 1411, and the notch groove 1413 faces the probe head 133, so that the laser beam emitted by the laser source 145 passes through the light guide groove 1412, the limit groove 1411, and the notch groove 1413 to the probe head 133. In a specific application, since the support member 141 includes a limit groove 1411, a light guide groove 1412, and a notch groove 1413, the limit groove 1411 is located at the end of the support member 141, the light guide groove 1412 connects the laser source 145 and the limit groove 1411, the reflecting prism 143 slides on the limit groove 1411, the notch groove 1413 is connected below the limit groove 1411, the fixture 142 fixes the clamping portion 131 to one side of the limit groove 1411, and the notch groove 1413 faces the probe head 133. Thus, by adjusting the position of the reflecting prism 143 in the limit groove 1411, the position where the laser is reflected to the probe head 133 is forced to change, and further, the angle change of the laser reflected by the probe head 133 is generated according to the deformation of the cantilever 132 or the probe head 133.

[0033] In one possible embodiment, the optical module 140 further includes a first fastener 146 and a second fastener 147. The first fastener 146 is connected to the reflective prism 143 parallel to the light guide groove 1412, and the second fastener 147 abuts against the reflective prism 143 perpendicular to the light guide groove 1412, so that the reflective prism 143 can adjust its relative position with respect to the limiting groove 1411. In a specific application, the first fastener 146 is first rotated to move the reflective prism 143 forward or backward in the limiting groove 1411 along the direction of the light guide groove 1412. Then, the second fastener 147 is rotated to fix the reflective prism 143 to the limiting groove 1411, thereby adjusting the relative position of the reflective prism 143 with respect to the limiting groove 1411, thereby adjusting the position of the laser beam reflected from the reflective prism 143 to the probe portion 133.

[0034] In one possible embodiment, aperture assembly 144 includes a first aperture piece 1441 and a second aperture piece 1442, which are spaced apart on light guide slot 1412. In a specific application, a laser beam emitted by laser source 145 is narrowed by first aperture piece 1441 and second aperture piece 1442, which are spaced apart on light guide slot 1412. The laser beam is then reflected by reflective prism 143 onto the reflective surface of probe portion 133, and ultimately onto detector 152.

[0035] In one possible embodiment, the optical lever detection device 100 for a Micro LED chip further includes a digital terminal 160, which is electrically connected to a monitoring camera 151 and a detector 152, respectively. In a specific application, the force-deforming member 130 converts the deformation into an angular displacement of the laser beam. The monitoring camera 151 and the detector 152 transmit the laser beam displacement to the digital terminal 160, which converts the angular displacement of the laser beam into an electrical signal to calculate the real-time chip bonding force. When the real-time bonding force reaches a critical bonding force, the sample translation stage 110 is controlled to stop moving. Example

[0036] Compared with the first embodiment, the subject matter of this embodiment is different, as follows: Please refer to Figure 8 The second embodiment of the present invention provides an optical lever detection method for a Micro Led chip, which is applicable to the optical lever detection device 100 of the Micro Led chip described above, and includes the following steps: S1, input the bonding force level between the chip to be tested 120 and the substrate 121; S2. Mount the chip to be detected 120 on the sample displacement stage 110, and control the sample displacement stage 110 to move the chip to be detected 120 to a target detection position so that the probe portion 133 contacts the chip to be detected 120; S3, the sample displacement stage 110 continues to drive the chip to be tested 120 to move toward the probe portion 133, so that the probe portion 133 generates an extrusion force, and the extrusion force forces the deformable member 130 to deform; S4, the detection module 150 detects the deformation of the force-deforming member 130 and converts it into the angular displacement of the laser beam; S5, the monitoring camera 151 and the detector 152 transmit the displacement of the laser beam to the digital terminal 160, and the digital terminal 160 converts the angular displacement of the laser beam into an electrical signal, calculates the real-time contact force of the force-deformation member 130, and when the real-time contact force of the force-deformation member 130 reaches the theoretical critical connection force between the chip to be tested 120 and the substrate 121, the sample displacement stage 110 is controlled to stop moving, and the status of the chip to be tested 120 is identified and judged by the monitoring camera 151. In a specific application, first determine the bonding force level between the chip to be tested 120 and the substrate 121. The bonding force levels correspond to the contact force levels of the stress-deformation member 130, and the bonding force levels are respectively the first level, the second level and the third level, that is, the contact force of the stress-deformation member 130 corresponds to the bonding force levels from low to high from small to large. The first level of bonding force is used to detect the qualified rate of the welding strength between the electrode of the chip to be tested 120 and the pad on the substrate 121. The second level of bonding force is used to detect the good rate of the welding strength between the electrode of the chip to be tested 120 and the pad on the substrate 121. The third level of bonding force is used to detect the excellent rate of the welding strength between the electrode of the chip to be tested 120 and the pad on the substrate 121. Install the chip to be tested 120 on the sample displacement stage 110, and control the sample displacement stage 110 to drive the chip to be tested 120 to move To the target detection position, so that the chip to be detected 120 conflicts with the probe part 133; the sample displacement stage 110 continues to drive the chip to be detected 120 to move toward the probe part 133, so that an extrusion force is generated between the two, and the extrusion force forces the force deformation member 130 to produce a deformation; the force deformation member 130 converts the deformation into an angular displacement of the laser beam, and the monitoring camera 151 and the detector 152 transmit the displacement of the laser beam to the digital terminal 160, and the digital terminal 160 converts the displacement of the laser beam into an electrical signal, thereby calculating the real-time contact force of the force deformation member 130. When the real-time contact force of the force deformation member 130 reaches the theoretical critical connection force between the chip to be detected 120 and the substrate 121, the sample displacement stage 110 is controlled to stop moving, and the monitoring camera is used to identify and judge whether the state of the chip to be detected is normal, displaced or detached. By detecting the real-time contact force and comparing it with the theoretical critical connection force (the critical connection force is the maximum external force required to separate the chip under test 120 and the substrate 121 when the two have a complete bonding area and optimal bonding strength. In this embodiment, the external force can be the squeezing force between the chip under test 120 and the probe part 133), the bonding strength between the electrode of the chip under test 120 and the pad on the substrate 121 can be distinguished as excellent, good, or qualified. This reduces the probability of problems such as uneven brightness, color deviation, pixel failure, and inconsistent response time in Micro LED displays, ensures overall display quality and performance, and improves the yield rate of Micro LED displays.

[0037] In a possible embodiment, the steps of ensuring that the contact force of the real-time force-deforming member 130 reaches the theoretical critical connection force between the chip to be detected 120 and the substrate include: When the theoretical critical connection force is much greater than the contact force of the real-time force deforming member 130, the reflective prism 143 is adjusted to move away from the probe part 133; when the contact force of the real-time force deforming member 130 gradually approaches the theoretical critical connection force from small to large, the reflective prism 143 is adjusted to move toward the probe part 133. In specific applications, when the theoretical critical connection force is much greater than the contact force of the real-time force deforming member 130, the deformation of the force deforming member 130 is mainly concentrated between the clamping part 131 and the cantilever 132. The reflective prism 143 is adjusted to move away from the probe part 133 so that the laser beam falls on the side of the probe part 133 close to the cantilever 132, thereby effectively identifying the connection strength between the chip to be tested 120 and the substrate 121 in batches during the process of continuously increasing the contact force of the force deforming member 130, and then distinguishing the welding strength between the electrode of the chip to be tested 120 and the pad on the substrate 121. The test results are as follows: excellent, good and qualified grades; when the contact force of the real-time force-deformation member 130 gradually approaches the theoretical critical connection force from small to large, the deformation of the force-deformation member 130 is not only concentrated between the clamping part 131 and the cantilever 132, but also distributed between the cantilever 132 and the probe part 133. The reflective prism 143 is adjusted to move toward the probe part 133 so that the laser beam falls on the side of the probe part 133 away from the cantilever 132, thereby effectively identifying the larger bonding force between the chip 120 to be detected and the substrate 121, thereby improving the detection adaptability range of the optical lever detection device 100.

[0038] The above embodiments merely illustrate several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. An optical lever detection device for a Micro Led chip, characterized in that: Comprising: A sample displacement stage for loading the chip to be detected and moving the chip to be detected to the target detection position; A force deformation member, which includes a clamping portion, a cantilever, and a probe head. The two ends of the cantilever are respectively connected to the clamping portion and the probe head, and the probe head abuts against the chip to be detected; An optical module, which includes a support member, a fixture, a reflecting prism, a diaphragm assembly, and a laser source. The fixture is connected to one end of the support member for connecting the clamping portion. The reflecting prism slides on the support member and is located above the clamping portion. The laser source is located at a position of the support member away from the reflecting prism, and the diaphragm assembly is located between the laser source and the reflecting prism; A detection module, which includes a monitoring camera and a detector. The monitoring camera is located above the probe head for identifying the relative position between the force deformation member and the chip to be detected, and the detector is located in the obliquely upward direction of the probe head; Wherein, the chip to be detected is connected to the substrate to generate a bonding force. The laser source emits a laser beam through the diaphragm assembly to the reflecting prism, and the laser beam is reflected by the reflecting prism to the surface of the probe head. The angle information of the light reflected by the surface of the probe head is identified and received by the detector. When the amount of deformation of the probe head in contact with the chip to be detected is different, the angle of the light reflected by the surface of the probe head changes to detect the magnitude of the contact force between the chip to be detected and the probe head.

2. The optical lever detection device of Micro Led chip according to claim 1, characterized in that: Denote the contact force between the probe head and the chip to be detected as F, the flexural rotation angle between the cantilever and the clamping portion as α, and the flexural rotation angle α is positively correlated with the contact force F.

3. The optical lever detection device of Micro Led chip according to claim 2, characterized in that: Denote the bonding force between the chip to be detected and the substrate as f, the point where the laser beam hits the probe head as the light spot, the side surface of the probe head in contact with the chip to be detected as the contact surface, the horizontal distance from the light spot to the contact surface as l, and the horizontal distance from the contact surface to the cantilever as L. When 0 < F ≤ 1 / 2f, l = 2 / 3L; when 1 / 2f < F ≤ f, l = 1 / 3L.

4. The optical lever detection device of Micro Led chip according to claim 3, characterized in that: The probe head is obliquely downwardly connected to the end of the cantilever. Denote the flexural rotation angle between the cantilever and the probe head as β. When 1 / 2f < F ≤ f, the flexural rotation angle β is positively correlated with the bonding force f.

5. The optical lever detection device of Micro Led chip according to any one of claims 1 to 4, characterized in that: The support member includes a limit groove, a light guide groove, and a notch groove. The limit groove is located at the end of the support member. The light guide groove communicates the laser source with the limit groove. The reflecting prism slides on the limit groove. The notch groove communicates below the limit groove. The fixture fixes the clamping portion to one side of the limit groove, and the notch groove is opposite to the probe head, so that the laser beam emitted by the laser source passes through the light guide groove, the limit groove, and the notch groove to the probe head respectively.

6. The optical lever detection device of Micro Led chip according to claim 5, characterized in that: The optical module further includes a first fastener and a second fastener. The first fastener is connected to the reflecting prism in the direction parallel to the light guide groove, and the second fastener abuts against the reflecting prism in the direction perpendicular to the light guide groove, so as to adjust the relative position of the reflecting prism and the limit groove.

7. The optical lever detection device of Micro Led chip according to claim 5, characterized in that: The aperture assembly includes a first aperture plate and a second aperture plate, and the first aperture plate and the second aperture plate are spaced apart and located on the light guide groove.

8. The optical lever detection device of Micro Led chip according to claim 1, characterized in that: The optical lever detection device of the MicroLed chip further comprises a digital terminal, and the digital terminal is electrically connected to the monitoring camera and the detector respectively.

9. A method for detecting an optical lever of a Micro Led chip, characterized in that: An optical lever detection device for a Micro Led chip according to any one of claims 1 to 8, comprising the steps of: S1. Input the bonding force level between the chip to be tested and the substrate; S2, installing the chip to be detected on the sample displacement stage, and controlling the sample displacement stage to drive the chip to be detected to move to a target detection position so that the probe part contacts the chip to be detected; S3, the sample displacement stage continues to drive the chip to be detected to move toward the probe part, so that the probe part generates a squeezing force, and the squeezing force forces the force-deformable member to generate a deformation; S4, the detection module detects the deformation of the force-deformed member and converts it into an angular displacement of the laser beam; S5. The monitoring camera and the detector transmit the displacement of the laser beam to the digital terminal, and the digital terminal converts the angular displacement of the laser beam into an electrical signal, calculates the real-time contact force of the force-deformation component, and when the real-time contact force of the force-deformation component reaches the theoretical critical connection force between the chip to be detected and the substrate, controls the sample displacement stage to stop moving, and identifies and determines the state of the chip to be detected through the monitoring camera.

10. The optical lever detection method of Micro Led chip according to claim 9, characterized in that: The contact force of the real-time force deformation member reaches the theoretical critical connection force between the chip to be detected and the substrate, comprising the following steps: When the theoretical critical connection force is much larger than the real-time contact force of the force deformation member, the reflective prism is adjusted to move away from the probe part; when the real-time contact force of the force deformation member gradually approaches the theoretical critical connection force from small to large, the reflective prism is adjusted to move toward the probe part.

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