A planar stretching type Mini-LED chip film expanding device and method capable of correcting errors

Abstract

The present invention belongs to the technical field of Mini-LED chip manufacturing, and discloses a planar stretching type Mini-LED chip film expanding device and method capable of correcting errors. A planar stretching type chip film expanding device capable of correcting errors includes a first film expanding mechanism, a second film expanding mechanism, a film pressing frame, a scanning camera and an error correction mechanism. The first film expanding mechanism and the second film expanding mechanism are used to stretch the blue film as a whole. Subsequently, the scanning camera detects the positions of the chips on the blue film. The correction plate adsorbs and fixes the part of the blue film where the positions of the chips do not shift through the adsorption through holes, and then the marbles jack up the part of the blue film where the chips shift and are not fixed, locally expanding the blue film, so that the positions of the chips on the blue film are corrected to accurately adjust the chip positions, solving the problems that the conventional film expanding device cannot arbitrarily adjust the local stretching amount of the blue film and cannot correct the local chip position shift.

Description

Technical Field

[0001] The present invention belongs to the technical field of Mini-LED chip manufacturing, and particularly relates to a planar stretching type Mini-LED chip film expanding device and method capable of correcting errors. Background Art

[0002] In semiconductor chip manufacturing, after the chips are batch-produced on the wafer, the chips are still an integral whole, and only after scribing and segmentation can the common small chips be formed. The distance between the chips is the distance of the cutting line. For Mini-LED chips with a size of about a hundred micrometers, it is difficult to achieve chip transfer and packaging at an extremely small distance. Therefore, it is also necessary to go through a film expanding process to increase the distance between the chips.

[0003] The traditional Mini-LED chip film expanding method is as follows: Place the blue film in the middle of a ring and fix it, and then use a cylinder to lift the blue film part from the middle of the ring, so that the blue film is stretched as a whole, thereby increasing the distance between the chips on the blue film.

[0004] However, the stretching deformation of the blue film is easily affected by factors such as temperature, strain, and stretching speed. It is difficult for the chips to expand uniformly from the center. In actual situations, the chips in the central area are often over-expanded, while the chips in the four corners are under-expanded. This method obviously cannot meet the requirements of the Mini-LED chips being horizontal and vertical. Moreover, even if errors occur after film expansion, they cannot be corrected anymore, which greatly affects the accuracy of subsequent chip transfer. Summary of the Invention

[0005] Aiming at the above defects, the purpose of the present invention is to provide a planar stretching type Mini-LED chip film expanding device and method capable of correcting errors, which expand the film in two perpendicular directions of the chip rows and columns, and can correct in the error area after film expansion, improving the arrangement accuracy of the chips after film expansion.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] A planar stretching type chip film expanding device capable of correcting errors, comprising a first film expanding mechanism, a second film expanding mechanism, a film pressing frame, a scanning camera, and an error correction mechanism;

[0008] The film expanding directions of the first film expanding mechanism and the second film expanding mechanism are arranged perpendicular to each other. The film pressing frame is used to fix the blue film with chips. The error correction mechanism is used for local expansion of the blue film. The scanning camera is used to detect the positions of the chips on the blue film;

[0009] The error correction mechanism includes a correction disk, a plurality of balls, and a ball driving mechanism. The correction disk is provided with a plurality of adsorption through-holes and a plurality of correction through-holes. The adsorption through-holes are evenly distributed on the correction disk, and each of the plurality of adsorption through-holes is externally connected to an air extraction mechanism. The adsorption through-holes are used to adsorb and fix the blue film on the upper surface of the correction disk when the air extraction mechanism is started. The correction through-holes are evenly distributed between the adsorption through-holes. The balls are arranged to move up and down in the correction through-holes, with one ball corresponding to one correction through-hole. The up-and-down movements of the plurality of balls are independent of each other. Driven by the ball driving mechanism, at least one of the balls moves upward and protrudes from the upper surface of the correction disk, and the ball that moves upward and protrudes is used to locally expand the blue film.

[0010] Preferably, a porous ceramic is arranged in the adsorption through-hole, and the porous ceramic is flush with the upper surface of the correction disk. The adsorption through-hole is connected to an external air extraction mechanism through a first air pipe, and the air extraction mechanism is a negative pressure pump.

[0011] The ball is arranged at one end of the correction through-hole close to the upper surface of the correction disk. The ball is of a cylindrical structure, and the upper end of the ball is hemispherical. A seal is provided between the outer wall of the ball and the inner wall of the correction through-hole. When the ball does not move upward, the upper end of the ball does not protrude beyond the upper surface of the correction disk. The other end of the correction through-hole is connected to a second air pipe, and the second air pipe is connected to the ball driving mechanism. The ball driving mechanism is an external air pressure adjustment system.

[0012] Preferably, the adsorption through-hole is a cylindrical through-hole with a diameter of 1 mm, and the correction through-hole is a cylindrical through-hole with a diameter of 1.5 mm.

[0013] Preferably, it further includes a rotation driver for driving the correction disk to rotate in the horizontal direction.

[0014] Preferably, the film pressing frame includes a first film pressing frame and a second film pressing frame. The first film pressing frame and the second film pressing frame are arranged one above the other, and the first film pressing frame can be buckled to the second film pressing frame. The buckling of the first film pressing frame and the second film pressing frame is used to clamp and fix the stretched blue film.

[0015] The second film pressing frame is provided with a raised platform, and the raised platform is flush with the upper surface of the correction disk. The film pressing frame is square, and the side length of the film pressing frame is less than the length L2 of the second film expanding mechanism.

[0016] Preferably, it further includes a number of press frame column heads. The press frame column heads are provided with first through holes. A push block is arranged in the first through holes. A seal is provided between the push block and the inner wall of the first through holes. One side of the first through hole is connected to a third air pipe, and the third air pipe is connected to an external first air pump. A locking arrow is installed on the side of the push block away from the third air pipe. The locking arrow is used to lock the first press film frame and the second press film frame. The first press film frame and the second press film frame are respectively provided with a number of locking through holes, and the first through holes and the locking through holes are matched;

[0017] Under the control of the first air pump, the push block can push the locking arrow to move downward and sequentially pass through the locking through holes of the first press film frame and the locking through holes of the second press film frame.

[0018] Preferably, the first film expanding mechanism includes a first roller group and a first pressing block group. The first roller group and the first pressing block group are arranged opposite and parallel to both sides of the error correction mechanism in the second direction. The first roller group is used to stretch the blue film in the first direction, and the first pressing block group is used to fix the blue film in the first direction;

[0019] The second film expanding mechanism includes a second roller group and a second pressing block group. The second roller group and the second pressing block group are arranged opposite and parallel to both sides of the error correction mechanism in the first direction. The second roller group is used to stretch the blue film in the second direction, and the second pressing block group is used to fix the blue film in the second direction;

[0020] The first direction is perpendicular to the second direction. The lengths of the second roller group and the second pressing block group are the same. The second roller group and the second pressing block group are arranged between the first roller group and the first pressing block group, and the second roller group is arranged at an interval from the first roller group and the first pressing block group;

[0021] The first roller group includes a pair of first upper rollers and first lower rollers which are arranged opposite to each other. The first upper roller and the first lower roller are arranged directly opposite to each other, and the first upper roller and the first lower roller are respectively arranged on both sides of the blue film in the thickness direction;

[0022] The first pressing block group includes a pair of first upper pressing blocks and first lower pressing blocks which are arranged opposite to each other. The first upper pressing block and the first lower pressing block are arranged directly opposite to each other, and the first upper pressing block and the first lower pressing block are respectively arranged on both sides of the blue film in the thickness direction;

[0023] The second roller group includes a pair of second upper rollers and second lower rollers which are arranged opposite to each other. The second upper roller and the second lower roller are arranged directly opposite to each other, and the second upper roller and the second lower roller are respectively arranged on both sides of the blue film in the thickness direction;

[0024] The second pressing block group includes oppositely arranged second upper pressing blocks and second lower pressing blocks. The second upper pressing blocks and the second lower pressing blocks are arranged opposite to each other, and the second upper pressing blocks and the second lower pressing blocks are respectively arranged on both sides in the thickness direction of the blue film.

[0025] Preferably, a spacing adjustment device is arranged between the first upper roller and the first lower roller. The spacing adjustment device is used to adjust the distance between the first upper roller and the first lower roller. The spacing between the first upper roller and the first lower roller is adjustable within the range of 0 - 10 mm. A spacing adjustment device is arranged between the second upper roller and the second lower roller. The spacing adjustment device is used to adjust the distance between the second upper roller and the second lower roller. The spacing between the second upper roller and the second lower roller is adjustable within the range of 0 - 10 mm. The first upper roller, the first lower roller, the second upper roller, and the second lower roller are provided with fine knurling with a module of 0.2 mm. A spacing adjustment device is arranged between the first upper pressing block and the first lower pressing block. The spacing adjustment device is used to adjust the distance between the first upper pressing block and the first lower pressing block. The spacing between the first upper pressing block and the first lower pressing block is adjustable within the range of 0 - 10 mm. A spacing adjustment device is arranged between the second upper pressing block and the second lower pressing block. The spacing adjustment device is used to adjust the distance between the second upper pressing block and the second lower pressing block. The spacing between the second upper pressing block and the second lower pressing block is adjustable within the range of 0 - 10 mm.

[0026] The length of the first film expanding mechanism is L1, and the length of the second film expanding mechanism is L2. Define the side length of the maximum square range allowed after the chip film is expanded as L3. L3 < L2 < L1. A gap d in the length direction of the second film expanding mechanism is arranged between the first film expanding mechanism and the second film expanding mechanism.

[0027] L3 is less than 80 mm; L2 is 20 mm larger than the side length of the pressure film frame; L1 is larger than the side length of the unexpanded blue film; d is greater than 30 mm.

[0028] An error correction method for a planar stretching type chip film expanding device, using the above-mentioned planar stretching type chip film expanding device, includes the following steps:

[0029] A. Placing the blue film and starting: Place the blue film with the chip on the correction plate, and start the scanning camera to observe the spacing of the chips on the blue film in real time.

[0030] B. First two-way film stretching: Use the first film stretching mechanism to stretch the blue film until the distance between any two adjacent chips in the first direction reaches 96% of the set spacing, and use the second film stretching mechanism to stretch the blue film until the distance between any two adjacent chips in the second direction reaches 96% of the set spacing. The set spacing is the spacing between adjacent chips required for the next process.

[0031] C. Error identification: Obtain the positions of all chips through a scanning camera, and judge whether the chip spacing in several areas is lower than 95% of the set spacing. If the chip spacing in this area is greater than or equal to 95% of the set spacing, mark this area as the adjusted area. If the chip spacing in this area is less than 95% of the set spacing, mark this area as the error area. Select one of the error areas and judge whether this error area is a convex polygon. If so, go to step D. If not, this error area is a concave polygon, divide it into several convex polygons and then go to step D. If this error area has reached the minimum adjustment range and cannot be divided, directly go to step D.

[0032] D. Error correction: Control the marbles corresponding to this error area in the correction plate to protrude upward, so that the blue film in this error area is lifted and stretched and expanded.

[0033] E. Error elimination verification: Use the scanning camera to re-identify the error area after error correction. If the chip spacing in this error area still does not all reach 95%, and this error area is not the minimum adjustable range, return to step C for re-identification and segmentation. If this error area is the minimum adjustable range, return to step D for repeated adjustment, and accumulate the adjustment times of this error area. When the accumulated adjustment times of this error area exceed the preset maximum adjustment times, give up adjusting this error area, and at the same time mark this error area as the adjusted area. Until all areas are marked as adjusted areas, go to step F.

[0034] F. Second two-way film stretching: Use the first film stretching mechanism to stretch the blue film after error elimination verification. The scanning camera observes the spacing of the chips in the first direction in real time. When the average chip spacing is equal to the set spacing, stop stretching. Use the second film stretching mechanism to stretch the blue film. The scanning camera observes the spacing of the chips in the second direction in real time. When the average chip spacing is equal to the set spacing, complete the stretching.

[0035] A Mini-LED chip film stretching device includes the above-mentioned planar stretching type film stretching device capable of correcting errors.

[0036] The technical solution provided by the present invention may include the following beneficial effects:

[0037] The first film expanding mechanism and the second film expanding mechanism are used to stretch the blue film as a whole. Then, a scanning camera detects the position of the chip on the blue film. The correction plate adsorbs and locally fixes the part of the blue film where the chip position does not shift through the adsorption through holes, and then uses a bullet to lift the part of the blue film where the chip shifts and is not fixed, locally expanding the blue film, so that the chip position on the blue film can be corrected to accurately adjust the chip position, solving the problem that the conventional film expanding device cannot arbitrarily adjust the local stretching amount of the blue film and cannot correct the local chip position shift.

[0038] By rotating the correction plate, the chip arrangement direction is adjusted to be parallel to the stretching direction of the film expanding device, solving the problem that it is difficult to calculate the position adjustment when the chip arrangement direction and the stretching direction are different.

[0039] By reserving sufficient buffer areas at the edge and the central area of the blue film to ensure uniform stretching of the central area of the blue film, the problem of irregular deformation in the central area of the blue film caused by insufficient buffer areas is solved.

[0040] By first stretching the blue film to 96% of the maximum chip pitch according to the chip pitch, a margin is provided for local error adjustment, preventing excessive expansion of the blue film, and at the same time preventing a large amount of expansion required during subsequent film expansion, resulting in an increase in the newly emerging error.

[0041] By adopting the method of dividing the error area and adjusting the chip pitch one by one in each area, ensuring that 99% of the chip pitches reach 95 - 96% of the preset maximum chip pitch during the error correction stage, reducing the final average chip offset. Brief Description of the Drawings

[0042] Figure 1 It is a schematic structural diagram of an embodiment of the present invention.

[0043] Figure 2 It is a schematic structural diagram of an embodiment of the present invention from another direction.

[0044] Figure 3 It is a working principle diagram of an embodiment of the present invention.

[0045] Figure 4 It is a partial enlarged view of a film pressing frame with a locking arrow of an embodiment of the present invention.

[0046] Figure 5 It is a three-dimensional schematic diagram of a first film pressing frame of an embodiment of the present invention.

[0047] Figure 6 It is a three-dimensional schematic diagram of a second film pressing frame of an embodiment of the present invention.

[0048] Figure 7 It is a cross-sectional view of a second film pressing frame of an embodiment of the present invention.

[0049] Figure 8 For Figure 7 The partial enlarged view at position A in

[0050] Wherein: the first film expanding mechanism 1, the second film expanding mechanism 2, the film pressing frame 3, the first film pressing frame 31, the second film pressing frame 32, the locking through hole 33, the convex platform 34, the scanning camera 4 and the error correction mechanism 5, the correction disc 51, several marbles 52, the adsorption through hole 53, the correction through hole 54, the porous ceramic 55, the pressing frame stud 6, the first through hole 61, the pushing block 62, the locking arrow 7, the chip 8;

[0051] The length L1 of the first film expanding mechanism, the length L2 of the second film expanding mechanism, the side length L3 of the maximum allowable square range after the chip is film-expanded, and the gap d between the first film expanding mechanism and the second film expanding mechanism along the length direction of the second film expanding mechanism. Specific embodiments

[0052] The embodiments of the present invention will be described in detail below. The examples of the embodiments are shown in the drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the drawings are exemplary and are only used to explain the present invention and should not be construed as a limitation of the present invention.

[0053] In the description of the present invention, it should be understood that the terms "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. In addition, the features defined as "first" and "second" may explicitly or implicitly include one or more of such features, used to distinguish and describe features, without order or importance.

[0054] In the description of the present invention, unless otherwise specified, the meaning of "a plurality" is two or more.

[0055] In the description of the present invention, it should be noted that, unless otherwise clearly defined and limited, the terms "installation", "connection", and "connection" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0056] The embodiments of the present invention will be described below in conjunction with the accompanying drawings.

[0057] A planar stretching type chip film expanding device capable of correcting errors includes a first film expanding mechanism 1, a second film expanding mechanism 2, a film pressing frame 3, a scanning camera 4 and an error correction mechanism 5.

[0058] The film expanding directions of the first film expanding mechanism 1 and the second film expanding mechanism 2 are arranged perpendicular to each other. The film pressing frame 3 is used to fix the blue film with the chip 8, the error correction mechanism 5 is used for local expansion of the blue film, and the scanning camera 4 is used to detect the position of the chip 8 on the blue film.

[0059] The error correction mechanism 5 includes a correction disk 51, a plurality of balls 52 and a ball driving mechanism. The correction disk 51 is provided with a plurality of adsorption through holes 53 and a plurality of correction through holes 54. The adsorption through holes 53 are evenly distributed on the correction disk 51. A plurality of the adsorption through holes 53 are respectively externally connected with an air extraction mechanism. The adsorption through holes 53 are used to adsorb and fix the blue film on the upper surface of the correction disk 51 when the air extraction mechanism is started. The correction through holes 54 are evenly distributed between the adsorption through holes 53. The balls 52 are arranged to move up and down in the correction through holes 54. One ball corresponds to one correction through hole. The up and down movements of the plurality of balls 52 are independent of each other. Driven by the ball driving mechanism, at least one of the balls 52 moves upward and protrudes from the upper surface of the correction disk. The ball 52 that moves upward and protrudes is used for local expansion of the blue film.

[0060] The target of chip transfer is a two-dimensional dot matrix on the substrate. During the transfer process, the die bonder head, the chip 8, and the dot matrix on the substrate need to be aligned one by one. If the accuracy of the chip 8 on the blue film is high enough, the error compensation movement of the blue film can be reduced, thereby improving the final transfer accuracy.

[0061] Adopting this structure, the first film expanding mechanism 1 and the second film expanding mechanism 2 are used to stretch the blue film as a whole. Then, the scanning camera 4 detects the position of the chip 8 on the blue film. The correction disk 51 adsorbs the part of the blue film where the position of the chip 8 does not shift (specifically, the part of the adjusted area) through the adsorption through holes 53, realizes local fixation of the blue film, and then uses the ball 52 to lift the part of the blue film where the chip 8 has a shift (specifically, the error area), locally expand the error area of the blue film, so that the position of the chip 8 on the error area of the blue film can be corrected to accurately adjust the position of the chip 8, solving the problem that the conventional film expanding device cannot arbitrarily adjust the local stretching amount of the blue film and cannot correct the local position shift of the chip 8.

[0062] The following is the average transfer error of the chip 8 for the blue film of the conventional film expansion and the film expansion with error correction in this solution on the same die bonder for chip transfer.

[0063] X-direction offset (μm) Y-direction offset (μm) Conventional film expansion 4.1 6.7 Film expansion with error correction in this solution 0.8 1.3

[0064] As Figure 1 and Figure 2 , in a specific embodiment, the correction disk 51 is a disk, and the adsorption through-holes 53 are distributed in a two-dimensional array on the correction disk 51. The adsorption through-holes 53 are connected to an external vacuum pump through air pipes, and the vacuum pump provides negative pressure to adsorb and fix the blue film by the adsorption through-holes 53; in a specific embodiment, a correction through-hole 54 is provided at the center of a rectangle formed by every four adjacent adsorption through-holes 53 that form a rectangle. The correction through-hole 54 is connected to an external air pressure adjustment system through an air pipe, and the air pressure adjustment system provides positive pressure or negative pressure to drive the ball 52 in the correction through-hole 54 to move along the length direction of the correction through-hole 54.

[0065] Preferably, a porous ceramic 55 is provided in the adsorption through-hole 53. The porous ceramic 55 is flush with the upper surface of the correction disk 51. The adsorption through-hole 53 is connected to an external air extraction mechanism through a first air pipe, and the air extraction mechanism is a negative pressure pump;

[0066] The ball 52 is arranged at one end of the correction through-hole 54 close to the upper surface of the correction disk 51. The ball 52 is of a cylindrical structure, and the upper end of the ball 52 is hemispherical. A seal is provided between the outer wall of the ball 52 and the inner wall of the correction through-hole 54. When the ball 52 does not move upward, the upper end of the ball 52 does not protrude beyond the upper surface of the correction disk 51. The other end of the correction through-hole 54 is connected to a second air pipe, and the second air pipe is connected to a ball driving mechanism, and the ball driving mechanism is an external air pressure adjustment system.

[0067] With this structure, the porous ceramic 55 prevents the blue film from deforming when being adsorbed, affecting the position of the chip 8.

[0068] By using the air pressure adjustment system, the ball 52 in the correction through-hole 54 is controlled to extend to jack up the blue film in a specified area, and the length of the extension of the ball 52 is controlled by adjusting the air pressure to accurately adjust the position of the local chip 8 on the blue film.

[0069] In a specific embodiment, by adding a sealing ring outside the ball 52, the sealed connection between the ball 52 and the inner wall of the correction through-hole 54 is ensured.

[0070] Preferably, the adsorption through-hole 53 is a cylindrical through-hole with a diameter of 1 mm, and the correction through-hole 54 is a cylindrical through-hole with a diameter of 1.5 mm.

[0071] Preferably, it further includes a rotation driver for driving the rotation of the correction disk 51 in the horizontal direction.

[0072] In a specific embodiment, a stepper motor is selected as the rotation driver to drive the correction disk 51 to rotate in place. When the blue film is placed on the correction disk 51, by rotating the correction disk 51, the arrangement direction of the chips 8 can be adjusted to be parallel to the stretching direction of the film expanding device, solving the problem that it is difficult to calculate the adjustment position when the arrangement direction of the chips 8 and the stretching direction are not parallel.

[0073] Preferably, the film pressing frame 3 includes a first film pressing frame 31 and a second film pressing frame 32. The first film pressing frame 31 and the second film pressing frame 32 are arranged one above the other. The first film pressing frame 31 can be buckled on the second film pressing frame 32, and the buckling of the first film pressing frame 31 and the second film pressing frame 32 is used to clamp and fix the stretched blue film.

[0074] The height from the inner frame edge to the outer frame edge of the second film pressing frame 32 gradually decreases, and an inclined surface frame that slopes outward and downward is formed on the upper surface of the second film pressing frame 32. A raised platform is provided at the inner frame edge of the second film pressing frame 32, and the raised platform 34 is flush with the upper surface of the correction disk 51. The film pressing frame 3 is square, and the side length of the film pressing frame 3 is less than the length L2 of the second film expanding mechanism 2.

[0075] The inclined surface frame is adopted to facilitate the positioning and buckling of the first film pressing frame 31 and the second film pressing frame 32. In a specific embodiment, the raised height of the raised platform 34 is 0.5 mm, ensuring that the blue film is placed flat on the upper surface of the correction disk 51.

[0076] Preferably, it further includes a plurality of film pressing frame studs 6. The film pressing frame studs 6 are provided with first through holes 61. A push block 62 is arranged in the first through holes 61. A seal is provided between the push block 62 and the inner wall of the first through holes 61. One side of the first through holes 61 is connected to a third air pipe, and the third air pipe is connected to an external first air pump. A locking arrow 7 is installed on the side of the push block 62 away from the third air pipe. The locking arrow 7 is used to lock the first film pressing frame 31 and the second film pressing frame 32. A plurality of locking through holes 33 are respectively arranged on the first film pressing frame 31 and the second film pressing frame 32, and the first through holes 61 and the locking through holes 33 are matched.

[0077] Under the control of the first air pump, the push block 62 can push the locking arrow 7 to move downward and sequentially pass through the locking through holes 33 of the first film pressing frame 31 and the locking through holes 33 of the second film pressing frame 32.

[0078] Such as Figure 2 and Figures 4 - 8, adopting this structure, the pushing block 62 in the first through hole 61 is pushed by the air supply of the first air pump. The pushing block 62 pushes the locking arrow 7, and the locking arrow 7 penetrates into the locking through hole 33 of the mold pressing frame and passes through the blue film clamped in the mold pressing frame 3, locking the stretched blue film for easy transfer.

[0079] In a specific embodiment, before the blue film is stretched, the first mold pressing frame 31 is fixed below several mold pressing column heads 6, and the mold pressing column heads 6 are connected to an external air cylinder. During stretching, the blue film is located between the first mold pressing frame 31 and the second mold pressing frame 32. When the stretching of the blue film is completed, the air cylinder pushes the mold pressing column heads 6, and the mold pressing column heads 6 push the first mold pressing frame 31 to move downward, buckling on the second mold pressing frame 32 below the blue film to clamp the stretched blue film.

[0080] Preferably, the material of the locking arrow 7 is polypropylene.

[0081] The locking arrow 7 is made of polypropylene, with a smooth surface and is easy to slide in the channel. At the same time, it has elasticity and relatively high strength, meeting the use requirements.

[0082] Preferably, the first film expanding mechanism 1 includes a first roller group and a first pressing block group. The first roller group and the first pressing block group are arranged opposite and parallel to both sides of the error correction mechanism 5 in the second direction. The first roller group is used to stretch the blue film in the first direction, and the first pressing block group is used to fix the blue film in the first direction;

[0083] The second film expanding mechanism 2 includes a second roller group and a second pressing block group. The second roller group and the second pressing block group are arranged opposite and parallel to both sides of the error correction mechanism 5 in the first direction. The second roller group is used to stretch the blue film in the second direction, and the second pressing block group is used to fix the blue film in the second direction;

[0084] The first direction is perpendicular to the second direction. The second roller group and the second pressing block group have the same length. The second roller group and the second pressing block group are arranged between the first roller group and the first pressing block group, and the second roller group is arranged with a gap from the first roller group and the first pressing block group;

[0085] The first roller group includes a pair of first upper rollers and first lower rollers which are arranged opposite to each other. The first upper roller and the first lower roller are arranged directly opposite to each other, and the first upper roller and the first lower roller are respectively arranged on both sides of the blue film in the thickness direction;

[0086] The first pressing block group includes a pair of first upper pressing blocks and first lower pressing blocks which are arranged opposite to each other. The first upper pressing block and the first lower pressing block are arranged directly opposite to each other, and the first upper pressing block and the first lower pressing block are respectively arranged on both sides of the blue film in the thickness direction;

[0087] The second roller set includes an oppositely arranged second upper roller and a second lower roller. The second upper roller and the second lower roller are arranged directly opposite to each other, and the second upper roller and the second lower roller are respectively arranged on both sides in the thickness direction of the blue film.

[0088] The second pressing block set includes an oppositely arranged second upper pressing block and a second lower pressing block. The second upper pressing block and the second lower pressing block are arranged directly opposite to each other, and the second upper pressing block and the second lower pressing block are respectively arranged on both sides in the thickness direction of the blue film.

[0089] With this structure, after the first roller set and the first pressing block set clamp the blue film, the blue film is stretched in the first direction by the rolling of the first roller set. After the second roller set and the second pressing block set clamp the blue film, the blue film is stretched in the second direction by the rolling of the second roller set.

[0090] Preferably, a spacing adjustment device is provided between the first upper roller and the first lower roller. The spacing adjustment device is used to adjust the distance between the first upper roller and the first lower roller. The spacing between the first upper roller and the first lower roller is adjustable within the range of 0 - 10 mm. A spacing adjustment device is provided between the second upper roller and the second lower roller. The spacing adjustment device is used to adjust the distance between the second upper roller and the second lower roller. The spacing between the second upper roller and the second lower roller is adjustable within the range of 0 - 10 mm. The first upper roller, the first lower roller, the second upper roller, and the second lower roller have fine knurling with a module of 0.2 mm. A spacing adjustment device is provided between the first upper pressing block and the first lower pressing block. The spacing adjustment device is used to adjust the distance between the first upper pressing block and the first lower pressing block. The spacing between the first upper pressing block and the first lower pressing block is adjustable within the range of 0 - 10 mm. A spacing adjustment device is provided between the second upper pressing block and the second lower pressing block. The spacing adjustment device is used to adjust the distance between the second upper pressing block and the second lower pressing block. The spacing between the second upper pressing block and the second lower pressing block is adjustable within the range of 0 - 10 mm.

[0091] The length of the first film expanding mechanism 1 is L1, and the length of the second film expanding mechanism 2 is L2. Define the side length of the maximum allowable square range after the chip 8 is film-expanded as L3. L3 < L2 < L1. A gap d is provided between the first film expanding mechanism 1 and the second film expanding mechanism 2 along the length direction of the second film expanding mechanism 2.

[0092] L3 is less than 80 mm; L2 is 20 mm larger than the side length of the film pressing frame 3; L1 is larger than the side length of the unexpanded blue film; d is larger than 30 mm.

[0093] The blue film can be conveniently clamped and loosened through the rollers and pressing block sets with adjustable spacing, so as to improve the overall processing efficiency.

[0094] In a specific embodiment, a spring buckle is used to quickly adjust the distance between the roller group and the pressing block group. As a simple replacement, devices such as telescopic cylinders or motors can also be used for distance adjustment.

[0095] L1 is greater than the side length of the blue film before film expansion, ensuring that the entire blue film is within the clamping range of the first film expansion mechanism and ensuring uniform stretching of the entire blue film; L3 is designed to be less than 80 mm, and the film expansion size only needs to meet the subsequent transfer process of the chip 8. In the second and third film expansions, the edges of the blue film are fixed, and only the central area of the blue film is stretched. L2 is 20 mm longer than the side length of the film pressing frame 3, and d is greater than 30 mm, reserving a sufficient buffer area between the edge and the central area of the blue film to ensure uniform stretching of the central area of the blue film and solve the problem of irregular deformation in the center of the blue film caused by insufficient buffer area.

[0096] In a specific embodiment, the material of the film pressing frame 3 is 7075 aluminum alloy; the 7075 aluminum alloy selected for the film pressing frame 3 is light in weight and high in strength, suitable for mechanisms with high-frequency movement, and is easy to process at the same time.

[0097] Refer to Figure 3 , an error correction method for a planar stretching type chip film expansion device, using the above-mentioned planar stretching type chip film expansion device, including the following steps:

[0098] A. Place the blue film and start: Place the blue film with the chip 8 on the correction disk 51, and start the scanning camera 4 to observe the distance between the chips 8 on the blue film in real time;

[0099] B. First double-sided film expansion: Use the first film expansion mechanism 1 to stretch the blue film until the distance between any two adjacent chips 8 in the first direction reaches 96% of the set distance, and use the second film expansion mechanism 2 to stretch the blue film until the distance between any two adjacent chips 8 in the second direction reaches 96% of the set distance. The set distance is the distance between adjacent chips 8 required for the next process;

[0100] C. Error identification: Obtain the positions of all chips 8 through the scanning camera, and judge whether the chip spacing in several regions is less than 95% of the set distance. If the chip spacing in this region is greater than or equal to 95% of the set distance, mark this region as the adjusted region. If the chip spacing in this region is less than 95% of the set distance, mark this region as the error region, and judge whether this error region is a convex polygon. If so, enter step D. If not, this error region is a concave polygon, and it is divided into several convex polygons and then enter step D. If this error region has reached the minimum adjustment range and cannot be divided, directly enter step D;

[0101] D. Error correction: Control the marbles corresponding to the error area in the correction plate to protrude upward, so that the blue film in the error area is lifted, stretched and expanded;

[0102] E. Error elimination verification: Use a scanning camera to re-identify the error area after error correction. If the chip pitch within this error area still does not all reach 95%, and this error area is not the minimum adjustable range, then return to step C to re-identify and segment; if this error area is the minimum adjustable range, then return to step D to repeat the adjustment, and accumulate the adjustment times of this error area. When the accumulated adjustment times of this error area exceed the preset maximum adjustment times, give up adjusting this error area, and at the same time mark this error area as an adjusted area; until all areas are marked as adjusted areas, then enter step F;

[0103] F. Second double-sided film expansion: Use the first film expansion mechanism 1 to stretch the blue film after error elimination verification. The scanning camera 4 observes the pitch of the chips 8 in the first direction in real time. When the average pitch of the chips 8 is equal to the set pitch, stop stretching; use the second film expansion mechanism 2 to stretch the blue film. The scanning camera 4 observes the pitch of the chips 8 in the second direction in real time. When the average pitch of the chips 8 is equal to the set pitch, complete the stretching.

[0104] Adopting this method, through the cooperation of the scanning camera 4 and the marbles 52, the pitch of the chips 8 on any part of the blue film can be adjusted to reduce the error of the chip pitch after the blue film is stretched, and solve the problem that the chip pitch cannot be accurately adjusted by the conventional stretching method. The chips 8 on the blue film are stretched to 96% of the maximum chip pitch, providing a margin for local error adjustment. If it is greater than 96%, the margin is too small, which is likely to cause excessive expansion of the blue film. If it is less than 96%, the margin is too large, and when expanding the film later, the amount that needs to be expanded is larger, and the newly emerging error also becomes larger.

[0105] In a specific embodiment, step A further includes adjusting the angle of the chip 8 arrangement direction. After rotating the blue film through the correction plate and adjusting the chip 8 arrangement direction to be consistent with the stretching direction, then proceed to step B; when adjusting the error area, the adsorption through holes 53 outside the area turn on negative pressure, and the correction through holes 54 inside the area introduce gas to make the marbles 52 therein protrude 1 mm. Then the adsorption through holes 53 and the correction through holes 54 return to normal pressure to release the blue film. Due to the certain delay of the deformation of the blue film, wait for 15 seconds, and then use the scanning camera 4 to identify the area again. If the chip pitch still does not reach more than 95%, repeat the adjustment.

[0106] A Mini-LED chip film expansion device uses the above-mentioned planar stretching type film expansion device that can correct errors.

[0107] Embodiment

[0108] Blue film in place: The first film expanding mechanism 1 and the second film expanding mechanism 2 are separated vertically by a 10 mm gap. The blue film to be expanded is placed on the correction plate 51 with the chip 8 facing upwards. The chip 8 is close to the first pressing block group and the second pressing block group and does not exceed the range of the correction plate 51.

[0109] Angle adjustment: Through the detection of the scanning camera 4, taking the deflection angle of the center row of the chip 8 as the overall deflection angle, all the adsorption through holes 53 of the correction plate 51 turn on negative pressure to suck the blue film, rotate by the corresponding angle to eliminate the overall angle deviation of the blue film, all the adsorption through holes 53 of the correction plate 51 return to normal pressure to release the blue film, and then rotate in the opposite direction by the corresponding angle to complete the reset.

[0110] First two-way film expansion: Use the first film expanding mechanism 1 to clamp the blue film vertically. The first roller group rolls to stretch the blue film in the first direction. The scanning camera 4 observes the distance between adjacent chips 8 in the first direction in real time. The set distance is 300 μm. When the distance between adjacent chips 8 in the first direction reaches 288 μm, the first roller group stops rolling; Use the second film expanding mechanism 2 to clamp the blue film vertically. The second roller group rolls to stretch the blue film in the second direction. The scanning camera 4 observes the distance between adjacent chips 8 in the second direction in real time. The set distance is 300 μm. When the distance between adjacent chips 8 in the second direction reaches 288 μm, the second roller group stops rolling.

[0111] Error correction:

[0112] The scanning camera 4 obtains the positions of all the chips 8. The distances between the chips 8 in several areas are less than 285 μm. Select one of the areas with errors. If this area is a convex polygon, the adsorption through holes 53 outside the area turn on negative pressure, and the correction through holes 54 inside the area are filled with gas to make the balls 52 bulge 1 mm, and the blue film in this area expands slightly; If this area is a concave polygon, it is divided into multiple convex polygons and then the above operations are performed; After the operation, the adsorption through holes 53 and the correction through holes 54 return to normal pressure to release the blue film. After waiting for 15 seconds, use the scanning camera 4601 to identify the area again. If the distance between the chips 8 still does not reach more than 285 μm, the adjustment is repeated; If it is consistent with the whole and the distance is between 285 - 288 μm, go to the next area with errors for adjustment. Finally, the distances between 99% of the chips 8 are adjusted to the set distance between 285 - 288 μm.

[0113] Second two-way film expansion: The first roller group rotates to stretch the blue film outwards. During this period, the scanning camera 4 observes the spacing of the chip 8 in the first direction in real time. When the average spacing of the chip 8 is 300 μm, the rotation of the first roller group stops. The second roller group rotates to stretch the blue film outwards. During this period, the scanning camera 4601 observes the spacing of the chip 8 in the second direction in real time. When the average spacing of the chip 8 is 300 μm, the second roller group stops rotating.

[0114] Fixing the film pressing frame 3: All the pressing frame columns 6 drop synchronously, moving the first film pressing frame 31 downwards and closely fitting it to the second film pressing frame 32. The first film pressing frame 31 and the second film pressing frame 32 fix the blue film. High-pressure gas is introduced into the first through hole 61 of the pressing frame column 6, and the locking arrow 7 pops out and penetrates into the locking through hole 33 to lock the first film pressing frame 31 and the second film pressing frame 32. The scanning camera 4 scans the positions of all the chips 8 on the blue film and stores the records.

[0115] End of film expansion: The first film expansion mechanism 1 and the second film expansion mechanism 2 are separated vertically to form a gap, the film pressing frame 3 is taken out, and the excess blue film is cut off with scissors.

[0116] Other components and operations according to the embodiments of the present invention are known to those of ordinary skill in the art and will not be described in detail here.

[0117] In the description of this specification, the descriptions referring to the terms "embodiment", "example", etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0118] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and purposes of the present invention. The scope of the present invention is defined by the claims and their equivalents.

Claims

1. A planar stretching chip film expansion device capable of correcting errors, characterized in that: It includes a first film expanding mechanism, a second film expanding mechanism, a film pressing frame, a scanning camera and an error correction mechanism; The film expansion direction of the first film expansion mechanism and the film expansion direction of the second film expansion mechanism are arranged perpendicular to each other, the film pressing frame is used to fix the blue film with the chip, the error correction mechanism is used for local expansion of the blue film, and the scanning camera is used to detect the position of the chip on the blue film; The error correction mechanism includes a correction disk, a plurality of pins and a pin driving mechanism. The correction disk is provided with a plurality of adsorption through holes and a plurality of correction through holes. The adsorption through holes are evenly distributed on the correction disk. The plurality of adsorption through holes are respectively connected to an exhaust mechanism. The adsorption through holes are used to adsorb and fix the blue film on the upper surface of the correction disk when the exhaust mechanism is activated. The correction through holes are evenly distributed between the adsorption through holes. The pins are movably arranged in the correction through holes, one pin corresponds to one correction through hole, and the upward and downward movements of the plurality of pins are separate and independent. When driven by the pin driving mechanism, at least one of the pins moves upward and protrudes from the upper surface of the correction disk. The pins that move upward and protrude are used to locally expand the blue film.

2. The error-correctable planar stretching chip film expansion device according to claim 1, characterized in that: A porous ceramic is arranged in the adsorption through hole, and the porous ceramic is flush with the upper surface of the correction disk. The adsorption through hole is connected to an external air pumping mechanism through a first air pipe, and the air pumping mechanism is a negative pressure pump; The pin is arranged in the correction through hole at one end close to the upper surface of the correction disk. The pin is a cylindrical structure, and the upper end of the pin is hemispherical. The outer wall of the pin is sealed with the inner wall of the correction through hole. The upper end of the pin does not exceed the upper surface of the correction disk when it does not move upward. The other end of the correction through hole is connected to the second air pipe, and the second air pipe is connected to the pin driving mechanism. The pin driving mechanism is an external air pressure adjustment system.

3. The error-correctable planar stretching chip film expansion device according to claim 2, characterized in that: The adsorption through hole is a cylindrical through hole with a diameter of 1 mm, and the correction through hole is a cylindrical through hole with a diameter of 1.5 mm.

4. The error-correctable planar stretching chip film expansion device according to claim 1, characterized in that: The invention also comprises a rotation drive, wherein the rotation drive is used for driving the correction disk to rotate in a horizontal direction.

5. The error-correctable planar stretching chip film expansion device according to claim 1, characterized in that: The film pressing frame comprises a first film pressing frame and a second film pressing frame, wherein the first film pressing frame and the second film pressing frame are arranged one above the other, and the first film pressing frame can be buckled with the second film pressing frame, and the buckling of the first film pressing frame and the second film pressing frame is used to clamp and fix the stretched blue film; The height from the inner frame edge of the second film pressing frame to the outer frame edge gradually decreases, and a slope frame inclined outward and downward is formed on the upper surface of the second film pressing frame. A raised platform is provided on the inner frame edge of the second film pressing frame, and the raised platform is flush with the upper surface of the correction disk. The film pressing frame is square, and the side length of the film pressing frame is less than the length L2 of the second film expanding mechanism.

6. The error-correctable planar stretching chip film expansion device according to claim 5, characterized in that: It also includes a plurality of press frame column heads, wherein the press frame column heads are provided with a first through hole, a push block is provided in the first through hole, the push block is sealed with the inner wall of the first through hole, one side of the first through hole is connected to a third air pipe, the third air pipe is connected to an external first air pump, a locking arrow is installed on the side of the push block away from the third air pipe, the locking arrow is used to lock the first film pressing frame and the second film pressing frame, the first film pressing frame and the second film pressing frame are respectively provided with a plurality of locking through holes, and the first through hole matches the locking through holes; Under the control of the first air pump, the pushing block can push the locking arrow to move downward and pass through the locking through hole of the first film pressing frame and the locking through hole of the second film pressing frame in sequence.

7. The error-correctable planar stretching chip film expansion device according to claim 1, characterized in that: The first film expansion mechanism comprises a first roller group and a first pressing block group, the first roller group and the first pressing block group are arranged oppositely and parallel to the two sides of the error correction mechanism in the second direction, the first roller group is used to stretch the blue film in the first direction, and the first pressing block group is used to fix the blue film in the first direction; The second film expansion mechanism comprises a second roller group and a second pressing block group, the second roller group and the second pressing block group are arranged oppositely and parallel to the two sides of the error correction mechanism in the first direction, the second roller group is used to stretch the blue film in the second direction, and the second pressing block group is used to fix the blue film in the second direction; The first direction is perpendicular to the second direction, the second roller group and the second pressing block group have the same length, the second roller group and the second pressing block group are arranged between the first roller group and the first pressing block group, and a gap is arranged between the second roller group and the first roller group and the first pressing block group; The first roller group comprises a first upper roller and a first lower roller which are arranged opposite to each other, the first upper roller and the first lower roller are arranged opposite to each other, and the first upper roller and the first lower roller are respectively arranged on both sides of the blue film thickness direction; The first pressing block group includes a first upper pressing block and a first lower pressing block which are arranged opposite to each other. The first upper pressing block and the first lower pressing block are arranged opposite to each other, and the first upper pressing block and the first lower pressing block are respectively arranged on both sides of the blue film thickness direction; The second roller group comprises a second upper roller and a second lower roller which are arranged opposite to each other, the second upper roller and the second lower roller are arranged opposite to each other, and the second upper roller and the second lower roller are arranged on both sides of the blue film thickness direction respectively; The second pressing block group includes a second upper pressing block and a second lower pressing block which are arranged opposite to each other. The second upper pressing block and the second lower pressing block are arranged opposite to each other, and the second upper pressing block and the second lower pressing block are respectively arranged on both sides of the blue film thickness direction.

8. The error-correctable planar stretching chip film expansion device according to claim 7, characterized in that: A spacing adjustment device is provided between the first upper roller and the first lower roller. The spacing adjustment device is used to adjust the distance between the first upper roller and the first lower roller. The spacing between the first upper roller and the first lower roller is adjustable within the range of 0 to 10 mm. A spacing adjustment device is provided between the second upper roller and the second lower roller. The spacing adjustment device is used to adjust the distance between the second upper roller and the second lower roller. The spacing between the second upper roller and the second lower roller is adjustable within the range of 0 to 10 mm. The first upper roller, the first lower roller, the second upper roller, and the second lower roller have fine knurling with a module of 0.2 mm. A spacing adjustment device is provided between the first upper pressing block and the first lower pressing block. The spacing adjustment device is used to adjust the distance between the first upper pressing block and the first lower pressing block. The spacing between the first upper pressing block and the first lower pressing block is adjustable within the range of 0 to 10 mm. A spacing adjustment device is provided between the second upper pressing block and the second lower pressing block. The spacing adjustment device is used to adjust the distance between the second upper pressing block and the second lower pressing block. The spacing between the second upper pressing block and the second lower pressing block is adjustable within the range of 0 to 10 mm. The length of the first film expanding mechanism is L1, and the length of the second film expanding mechanism is L2. Define the side length of the maximum allowable square range after the chip film is expanded as L3. L3 < L2 < L1. A gap d is provided between the first film expanding mechanism and the second film expanding mechanism along the length direction of the second film expanding mechanism. L3 is less than 80 mm; L2 is 20 mm larger than the side length of the pressure film frame; L1 is greater than the side length of the unexpanded blue film; d is greater than 30 mm.

9. An error correction method for a planar stretching chip film expansion device, characterized in that: Using the planar stretching type chip film expanding device with error correction as claimed in any one of claims 1-8, the following steps are included: A. Placing the blue film and starting: Place the blue film with the chip on the correction plate, and start the scanning camera to observe the spacing of the chips on the blue film in real time. B. First two-way film expansion: Use the first film expanding mechanism to stretch the blue film until the distance between any two adjacent chips along the first direction reaches 96% of the set spacing. Use the second film expanding mechanism to stretch the blue film until the distance between any two adjacent chips along the second direction reaches 96% of the set spacing. The set spacing is the spacing between adjacent chips required for the next process. C. Error identification: Obtain the positions of all chips through the scanning camera, and judge whether the chip spacing in several areas is lower than 95% of the set spacing. If the chip spacing in this area is greater than or equal to 95% of the set spacing, mark this area as the adjusted area. If the chip spacing in this area is less than 95% of the set spacing, mark this area as the error area. Select one of the error areas and judge whether this error area is a convex polygon. If so, enter step D. If not, this error area is a concave polygon. Divide it into several convex polygons and then enter step D. If this error area has reached the minimum adjustment range and cannot be divided, directly enter step D. D. Error correction: Control the pins in the correction disk corresponding to the error area to extend upward, so that the blue film in the error area is lifted up and stretched; E. Error elimination verification: Use a scanning camera to re-identify the error area after error correction. If the chip spacing in the error area still does not reach 95% and the error area is not the minimum adjustable range, return to step C to re-identify and segment; if the error area is the minimum adjustable range, return to step D to repeat the adjustment and accumulate the number of adjustments of the error area. When the accumulated number of adjustments of the error area exceeds the preset maximum number of adjustments, the adjustment of the error area is abandoned and the error area is marked as an adjusted area; until all areas are marked as adjusted areas, enter step F; F. Second bidirectional film expansion: Use the first film expansion mechanism to stretch the blue film after error elimination and verification, and the scanning camera observes the spacing of the chips in the first direction in real time. When the average spacing of the chips is equal to the set spacing, the stretching is stopped; Use the second film expansion mechanism to stretch the blue film, and the scanning camera observes the spacing of the chips in the second direction in real time. When the average spacing of the chips is equal to the set spacing, the stretching is completed.

10. A Mini-LED chip film expansion device, characterized in that: A planar stretchable chip film expansion device with correctable errors as described in any one of claims 1-8.

Images