High-precision leveling device applied to micro LED mass transfer

Abstract

The utility model relates to the technical field of leveling equipment, and provides a high-precision leveling device applied to micro LED mass transfer, which comprises a temporary substrate and an installation reference structure, and the temporary substrate is fixed on the lower surface of the installation reference structure; a lower base plate is arranged above the rotary table, and a plurality of Z-axis displacement tables are installed on the lower base plate; the upper base plate is arranged above the lower base plate, and the Z-axis displacement table is connected with the bottom of the upper base plate; the TFT back plate is mounted on the upper substrate, and the TFT back plate is arranged on the lower side of the temporary substrate; the displacement sensor is installed on the upper base plate and corresponds to the Z-axis displacement table, and the top end of the displacement sensor abuts against the installation reference structure; and the displacement sensor and the TFT backboard are driven by the rotary table to rotate relative to the temporary substrate. According to the utility model, the unbalance amount is compensated by detecting the end face run-out of the temporary substrate, so that the high-precision leveling effect is achieved.

Description

TECHNICAL FIELD

[0001] The utility model relates to leveling equipment technical field, specifically, relates to a kind of applied in MicroLED huge quantity transfer high-precision leveling device. BACKGROUND

[0002] MicroLED huge quantity transfer refers to the process that millions or even tens of millions of micron-level LED dies are correctly and efficiently moved to the circuit substrate. This technology is a key step in MicroLED display technology, involving chip transfer from a growth substrate (such as a sapphire substrate) to a target substrate (such as a glass TFT substrate). However, it is still a challenge for the industry to transfer millions of μLEDs with micron-level size to the driving circuit substrate with high yield, high precision and high efficiency. During the μLED transfer process, as the transfer area increases (≮6 inches), the parallelism of the TFT backplane and the temporary substrate directly affects the transfer yield.

[0003] Currently, the transfer area in the industry is ≯50X50mm, and the transfer alignment is greater than the precision of 10um, so the parallelism requirement of the TFT backplane and the temporary substrate is relatively low, and the impact on the transfer yield is low. However, as the transfer area increases, the parallelism of the temporary substrate and the TFT backplane directly affects the transfer precision. Therefore, a leveling device is designed to facilitate high-precision adjustment of the TFT backplane and the temporary substrate. SUMMARY

[0004] The purpose of the utility model is to provide a kind of applied in MicroLED huge quantity transfer high-precision leveling device by detecting parallel surface circumferential bounce and compensating, realize high-precision leveling.

[0005] The embodiment of the utility model is realized by the following technical scheme: a kind of applied in MicroLED huge quantity transfer high-precision leveling device, including temporary substrate and installation reference structure, the temporary substrate is fixed on the lower surface of the installation reference structure;Rotary table, the upper of the rotary table is equipped with lower substrate, the lower substrate is installed with several Z-axis displacement stages;Upper substrate, it is equipped in the upper of the lower substrate, and the bottom of the Z-axis displacement stage is connected with the upper substrate;TFT backplane, it is installed on the upper substrate, and the TFT backplane is equipped on the lower side of the temporary substrate;Displacement sensor, it is installed on the upper substrate and is correspondingly arranged with the Z-axis displacement stage, the top end of displacement sensor is in abutment with the installation reference structure;The displacement sensor and the TFT backplane are rotated relative to the temporary substrate by the rotary table.

[0006] Further, the installation reference structure includes a first suction cup, and the temporary substrate is adsorbed in the middle of the first suction cup. A second suction cup is installed on the upper substrate, and the TFT backplane is adsorbed on the second suction cup.

[0007] Further, the lower end surface of the first suction cup is provided with an annular reference surface, and the top end of the displacement sensor abuts against the annular reference surface.

[0008] Further, the mounting reference structure further comprises a top plate, a base and a support column, the rotary table is mounted on the base, and two ends of the support column are connected with the top plate and the base respectively; and the first suction cup is fixedly connected to the top plate.

[0009] Further, a spherical hinge structure is arranged between the Z-axis displacement table and the upper substrate.

[0010] Further, the Z-axis displacement table is arranged at least three, and the Z-axis displacement tables are uniformly and spacedly arranged around the middle part of the lower substrate.

[0011] Further, a tensile tension spring is arranged between the upper substrate and the lower substrate, and the tensile tension spring is arranged close to the Z-axis displacement table.

[0012] The technical scheme of the embodiment of the utility model has at least the following advantages and beneficial effects: the utility model forms a detection surface through a plurality of displacement sensors, and is driven to rotate around the Z axis by the rotary table, the circumferential runout of the detection plane is detected, the runout value is compensated, the height parallelism between the two plates is realized, and high precision is achieved. BRIEF DESCRIPTION OF DRAWINGS

[0013] In order to more clearly illustrate the technical scheme of the embodiment of the utility model, the following will briefly introduce the drawings needed to be used in the embodiment, and it should be understood that the following drawings only show some embodiments of the utility model, and therefore should not be regarded as a limitation to the scope, and for those skilled in the art, other related drawings can also be obtained without creative labor on the premise of the drawings.

[0014] Figure 1 The structural schematic diagram of the high-precision leveling device for MicroLED mass transfer provided by the embodiment of the utility model is shown;

[0015] Figure 2 The front view of the high-precision leveling device for MicroLED mass transfer in the utility model is shown;

[0016] Figure 3 The exploded view of the leveling module of the utility model is shown;

[0017] Figure 4 The structural schematic diagram of the mounting reference structure in the utility model is shown;

[0018] Figure 5 The structural schematic diagram when the temporary substrate and the TFT back plate are leveled is shown.

[0019] Figure 6 The control schematic view of the leveling device in the utility model.

[0020] Icon: 1-mounting reference structure, 11-first suction cup, 111-annular reference surface, 12-top plate, 13-support column, 14-base, 2-temporary base plate, 3-rotary table, 4-lower base plate, 5-Z-axis displacement table, 51-ball hinge structure, 6-upper base plate, 61-second suction cup, 7-displacement sensor, 8-TFT back plate, 9-stretching tension spring. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be described clearly and completely below in combination with the drawings in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, rather than all the embodiments. The components of the embodiments of the utility model described and shown in the drawings here can be arranged and designed in various different configurations.

[0022] Therefore, the following detailed description of the embodiments of the utility model provided in the drawings is not intended to limit the scope of the claimed utility model, but only represents selected embodiments of the utility model. Based on the embodiments in the utility model, all other embodiments obtained by those of ordinary skill in the art without creative labor are within the scope of protection of the utility model.

[0023] It should be noted that: similar numbers and letters represent similar items in the following drawings, therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0024] EMBODIMENT

[0025] The following will be further illustrated in combination with specific embodiments, referring to Figures 1-6As shown, the embodiment is a kind of applied to MicroLED mass transfer high-precision leveling device, including temporary substrate 2 and installation reference structure 1, temporary substrate 2 is fixed on the lower surface of installation reference structure 1, i.e. temporary substrate 2 and installation reference structure 1 are in a stable state, i.e. temporary substrate 2 and installation reference structure 1 are located in the same plane;Rotary table 3, rotary table 3 is provided with lower substrate 4, lower substrate 4 is installed with several Z-axis displacement tables 5, the Z-axis displacement table 5 is located in a corner of lower substrate 4, which can drive the corner of the position to realize up and down micro movement;Upper substrate 6, which is provided above lower substrate 4, and the bottom of Z-axis displacement table 5 is connected with upper substrate 6;TFT backboard 8, which is installed on upper substrate 6, and TFT backboard 8 is provided on the lower side of temporary substrate 2;Displacement sensor 7, which is installed on upper substrate 6 and is arranged corresponding to Z-axis displacement table 5, the top end of displacement sensor 7 is in contact with installation reference structure 1;Displacement sensor 7 and TFT backboard 8 are driven to rotate relative to temporary substrate 2 by rotary table 3;Specifically, rotary table 3 can drive upper substrate 6, lower substrate 4, Z-axis displacement table 5 and TFT backboard 8 to rotate synchronously around Z-axis, and in the process of rotating one circle, displacement sensor 7 will detect the end face circumferential runout of temporary substrate 2 and installation reference structure 1 in rotating state, the plane where TFT backboard 8 is located is parallel to the plane where upper substrate 6 is located, and according to the detected runout imbalance, multiple Z-axis displacement tables 5 are controlled to adjust, so that the parallelism of TFT backboard 8 and temporary substrate 2 is improved.

[0026] As shown Figure 3 As shown above, the installation reference structure 1 includes a first suction cup 11, and the temporary substrate 2 is located below the first suction cup 11, providing a more stable and convenient fixing scheme, the first suction cup 11 is vacuum adsorbed on the back side of the temporary substrate 2, and the surface of the temporary substrate 2 is tightly attached to the first suction cup 11, and the temporary substrate 2 is adsorbed in the middle of the first suction cup 11;The second suction cup 61 is installed on the upper substrate 6, and the TFT backboard 8 is adsorbed on the second suction cup 61, and the first suction cup 11, the second suction cup 61, the temporary substrate 2 and the TFT backboard 8 all maintain a coaxial state.

[0027] As shown Figure 6 As shown, the lower end surface of the first suction cup 11 is provided with an annular reference surface 111, and the annular reference surface 111 is coplanar with the temporary substrate 2, which can be regarded as the moving track of the displacement sensor 7 when detecting runout, and the top end of the displacement sensor 7 is in contact with the annular reference surface 111, it should be noted that the mounting surface of the displacement sensor 7 is consistent with the adsorption surface of the second suction cup 61 where the TFT backboard 8 is adsorbed, so after detection and compensation, the parallelism between the mounting surface of the displacement sensor 7 and the annular reference surface 111, i.e. the parallelism of the TFT substrate and the temporary substrate 2.

[0028] AsFigure 4 As shown, the installation reference structure 1 further comprises a top plate 12, a base 14, and support columns 13, the turntable 3 is installed on the base 14, and the two ends of the support columns 13 are connected with the top plate 12 and the base 14 respectively, the support columns 13 located at the four corners of the base 14 can help to level the top plate 12, and the support columns 13 can also have telescopic adjustment capability, so that when the first suction cup 11 is fixedly connected to the top plate 12, the installation reference structure 1 completes the coarse leveling of the TFT back plate 8 and the temporary substrate 2, and cooperates with the fine leveling of the leveling module for use together.

[0029] In addition, referring to Figure 3 As shown, a spherical hinge structure 51 is arranged between the Z-axis displacement table 5 and the upper substrate 6 for connection, when the Z-axis displacement table 5 drives the upper substrate 6 to move up and down during leveling, the upper substrate 6 has high degree of freedom based on the spherical hinge structure 51, and on this basis, due to the high requirement for leveling accuracy, the spherical hinge structure 51 also has a small gap in the pair of kinematic pairs, and a tensile tension spring 9 is connected between the upper substrate 6 and the lower substrate 4, the elastic tension of the tensile tension spring 9 tightens the upper substrate 6 and the lower substrate 4, thereby realizing compensation for the gap, and the tensile tension spring 9 is arranged next to the Z-axis displacement table 5, and the tension of the tensile tension spring 9 can be maximally concentrated on the spherical hinge structure 51.

[0030] The Z-axis displacement table 5 in the embodiment is provided with at least three, realizing three-point leveling, which can adopt a manual adjustment and locking mode, or an electric control type, and the Z-axis displacement tables 5 are uniformly and spacedly distributed around the middle part of the lower substrate 4, the lower substrate 4 is arranged in a triangular shape, and each Z-axis displacement table 5 is installed at a sharp corner, the bounce of the displacement sensor 7 is analyzed by the displacement table controller, and the bounce difference is taken as a driving compensation value, realizing consistency with the Z-axis displacement, thereby ensuring high-precision parallelism of the TFT back plate 8 and the temporary substrate 2.

[0031] In addition, the leveling operation method applied to the MicroLED mass transfer high-precision leveling device is as follows, which comprises the following steps:

[0032] Debugging: adjust the Z-axis displacement table 5 so that the displacement sensor 7 is in contact with the end surface of the installation reference structure 1, and then rotate the turntable 3 by one revolution; record the bounce value and the corresponding bounce azimuth angle of the displacement sensor 7 in one revolution, adjust the Z-axis displacement table 5 to ensure that the bounce value in one revolution is within the detection accuracy of the displacement sensor 7, and complete the debugging;

[0033] Substrate installation: the Z-axis displacement table 5 moves by equal distance, and the temporary substrate 2 and the TFT back plate 8 are installed at the corresponding positions;

[0034] Data acquisition: the Z-axis displacement table 5 moves to the working position, and the data of a plurality of displacement sensors 7 are read respectively;

[0035] Leveling: the data difference of the displacement sensor 7 is compensated as the driving value of the Z-axis displacement table 5 to the upper substrate 6, and the upper substrate 6 is driven by the Z-axis displacement table 5 in multiple directions to complete leveling.

[0036] In summary, the leveling device and method make it easy to assemble and test, the leveling precision can reach ±0.5um, the cost of the constructed system is low, and the system can be directly applied to a production line.

[0037] The preferred embodiments of the utility model are merely used for limiting the utility model, and the utility model can be changed and varied for the person skilled in the art. Any modification, equivalent replacement, improvement and the like within the spirit and principle of the utility model should be included in the protection scope of the utility model.

Claims

1. A high-precision leveling device for mass transfer of MicroLEDs, characterized in that, It includes a temporary substrate (2) and a mounting reference structure (1), wherein the temporary substrate (2) is fixed to the lower surface of the mounting reference structure (1); A turntable (3) is provided above the turntable (3), and a lower base plate (4) is provided on the lower base plate (4), on which a plurality of Z-axis displacement stages (5) are installed; An upper substrate (6) is disposed above the lower substrate (4), and the Z-axis displacement stage (5) is connected to the bottom of the upper substrate (6). A TFT backplate (8) is mounted on the upper substrate (6) and the TFT backplate (8) is disposed on the lower side of the temporary substrate (2); The displacement sensor (7) is mounted on the upper base plate (6) and is arranged corresponding to the Z-axis displacement stage (5). The top of the displacement sensor (7) abuts against the mounting reference structure (1). The turntable (3) drives the displacement sensor (7) and the TFT backplate (8) to rotate relative to the temporary substrate (2).

2. The high-precision leveling device for mass transfer of MicroLEDs according to claim 1, characterized in that, The mounting reference structure (1) includes a first suction cup (11), and the temporary substrate (2) is adsorbed onto the middle of the first suction cup (11); A second suction cup (61) is mounted on the upper substrate (6), and the TFT backplate (8) is adsorbed onto the second suction cup (61).

3. The high-precision leveling device for mass transfer of MicroLEDs according to claim 2, characterized in that, The lower end face of the first suction cup (11) is provided with an annular reference surface (111), and the top end of the displacement sensor (7) abuts against the annular reference surface (111).

4. The high-precision leveling device for mass transfer of MicroLEDs according to claim 2, characterized in that, The mounting reference structure (1) also includes a top plate (12), a base (14) and a support column (13). The turntable (3) is mounted on the base (14), and the two ends of the support column (13) are connected to the top plate (12) and the base (14) respectively. The first suction cup (11) is fixedly connected to the top plate (12).

5. The high-precision leveling device for mass transfer of MicroLEDs according to claim 1, characterized in that, The Z-axis displacement stage (5) and the upper base plate (6) are connected by a ball joint structure (51).

6. The high-precision leveling device for mass transfer of MicroLEDs according to claim 5, characterized in that, At least three Z-axis displacement stages (5) are provided, and the Z-axis displacement stages (5) are evenly spaced around the middle of the lower substrate (4).

7. The high-precision leveling device for mass transfer of MicroLEDs according to claim 6, characterized in that, A tension spring (9) is connected between the upper substrate (6) and the lower substrate (4), and the tension spring (9) is arranged close to the Z-axis displacement stage (5).

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