Chip transfer device based on fluid self-assembly and transfer method thereof

Abstract

The application discloses a chip transfer device based on fluid self-assembly and a transfer method thereof, and belongs to the field of LED chip display. The device realizes efficient parallel transfer by means of fluid self-assembly and hole convex matching, and remarkably reduces manufacturing cost. The device realizes automatic posture correction of irregular chips by means of flow field disturbance and upwarp structure, and improves assembly yield. The device mainly comprises the following steps: providing a fluid tank, the fluid tank containing a suspension solution for transferring chips, and placing a carrier plate in the fluid tank, the surface of the carrier plate being spaced apart from each other and being provided with a plurality of groups of positioning convexes, the positioning convexes comprising large convexes and small convexes; forming a flow field with uniform and adjustable flow velocity in the fluid tank by means of a flow field generator, so that the chips to be transferred flow along a preset direction above the carrier plate along with the fluid; the chips to be transferred being provided with large holes and small holes, and the chips to be transferred being irregular chips, and the chips to be transferred having opposite front ends and rear ends. The application is mainly used for chip transfer based on fluid self-assembly.

Description

Technical Field

[0001] This invention relates to the field of LED chip display, and more particularly to a chip transfer device and method based on fluid self-assembly. Background Technology

[0002] In the field of LED displays, mass transfer accounts for a large proportion of the overall manufacturing cost. Existing mass transfer methods are inefficient, costly, and have low yields, which greatly limits the widespread application of LED chips in the display field.

[0003] Existing mass transfer technology involves peeling the chip from the substrate and then transferring it to the target location. During the mass transfer process, the process needs to be repeated: alignment → picking → moving → alignment → placement. Mass transfer of large quantities is time-consuming and costly.

[0004] Existing fluid transfer devices lack a precise orientation and positioning structure that matches the chip's aperture position, making it impossible to achieve self-alignment using the chip's own geometric features. Relying on external visual correction further slows down the process. Therefore, there is an urgent need to develop a mass transfer device and method that can adapt to irregularly tilted chips, achieve automatic posture correction and orientation fixation in the flow field through aperture-protrusion mating, and support rapid recycling of unassembled chips, in order to overcome the efficiency and yield bottlenecks of existing technologies. Summary of the Invention

[0005] The purpose of this invention is to provide a chip transfer device and method based on fluid self-assembly, which utilizes fluid self-assembly and hole-protrusion cooperation to achieve efficient parallel transfer, significantly reducing manufacturing costs; and uses flow field disturbance and tilting structure to achieve automatic orientation correction of irregular chips, thereby improving assembly yield.

[0006] This invention is achieved through the following technical solution: A chip transfer method based on fluid self-assembly includes the following steps: S1. A fluid tank is provided, the fluid tank contains a suspension for transferring chips, a carrier plate is placed in the fluid tank, and the surface of the carrier plate is arrayed with multiple sets of positioning protrusions, including large protrusions and small protrusions. S2. A uniform and adjustable flow field is formed in the fluid tank by a flow field generator, so that the chip to be transferred flows with the fluid above the carrier plate in a preset direction. The chip to be transferred has one large hole and two small holes, and the chip to be transferred is an irregularly shaped chip with a front end and a rear end. The rear end of the chip to be transferred is raised relative to the front end. S3. The flow field drives the chip to be transferred through the positioning area on the carrier. When the raised part of the rear end of the chip to be transferred passes the large bump and the small bump, under the combined action of fluid shear force and gravitational torque, the chip to be transferred adjusts its attitude and passes over the fixed chip to continue flowing downstream until the large hole on the chip to be transferred matches the large bump and the small hole matches the small bump and falls into the corresponding position to complete the fixation, or it passes over all the unmatched positioning bumps and enters the downstream recycling channel.

[0007] Furthermore, the specific process of attitude adjustment in step S3 includes: when the chip to be transferred flows over the large or small bump with its rear end raised, the large or small bump disturbs the fluid, forming a local eddy or pressure gradient region; the raised rear end of the chip to be transferred is subjected to the lifting force or lateral force of the local eddy or pressure gradient region, combined with the drag force of the mainstream fluid direction, causing the chip to be transferred to rotate and flip around its center of mass or front end fulcrum; when the chip to be transferred flips to a preset angle, the large hole is fitted around the outer periphery of the large bump, and the small hole is fitted around the outer periphery of the small bump, achieving self-locking fixation.

[0008] Furthermore, it also includes a chip recycling and circulation step: a recycling channel is set at the downstream end of the carrier board. Chips that have not been fixed on the carrier board are carried by the fluid and pass over the effective assembly area of ​​the carrier board directly into the recycling channel. The unassembled chips are collected through the recycling channel and transported back to the upstream inlet of the fluid tank for the next round of self-assembly transfer.

[0009] Furthermore, the flow field generator can adjust the flow rate, viscosity, or pulse frequency of the suspension and set a flow rate threshold so that the fluid drag force on the chip fixed on the large and small bumps is less than the mechanical interlocking force or adsorption force between it and the positioning bump, while the fluid drag force on the unfixed chip to be transferred is sufficient to overcome the frictional resistance between it and the carrier surface.

[0010] A chip transfer apparatus based on fluid self-assembly, used to implement the aforementioned chip transfer method based on fluid self-assembly, includes: Fluid tank: It has a cavity inside for fluid flow; Carrier board: It is detachably set in the fluid tank. The upper surface of the carrier board is arranged with multiple sets of positioning protrusions, including large protrusions and small protrusions. Each positioning protrusion can cooperate with the large holes, small holes and rear end protrusions on the irregularly shaped chip to be transferred to restrict the chip's degree of freedom. Flow field generator: Communicated with the fluid tank, used to drive the suspension containing the chip to be transferred to form a uniform and adjustable flow field in the fluid tank; Recovery channel: Located at the downstream end of the fluid tank, it is used to collect chips that failed to be assembled on the carrier and guide them back to the upstream or external storage container.

[0011] Furthermore, the flow field generator includes a pump body and a flow regulating valve for controlling the uniformity of the fluid velocity within the fluid tank.

[0012] Furthermore, the top shapes of the large and small bumps are complementary to the inner wall contours of the large and small holes on the chip to be transferred, respectively.

[0013] Furthermore, the heights of the large and small bumps are set as follows: when the chip to be transferred falls in the correct orientation, the chip body plane is parallel to or at a certain angle to the carrier board surface; when the chip to be transferred contacts in the wrong orientation, the large or small bump applies a reverse torque to the chip, causing it to bounce up and continue to move downstream with the fluid.

[0014] Compared with the prior art, the beneficial effects of the present invention are: 1. Achieving efficient parallel transfer by utilizing fluid self-assembly and hole-protrusion matching, significantly reducing manufacturing costs: The method uses fluid to drive the chip to flow above the carrier board, and achieves automatic positioning and fixation through geometric matching of large and small holes on the chip to be transferred with large and small protrusions on the carrier board; This method transforms individual operations into large-batch parallel self-assembly, eliminating the need for high-precision external visual correction equipment, greatly shortening the transfer cycle, and effectively solving the problems of low efficiency, expensive equipment, and high manufacturing costs of existing technologies.

[0015] 2. Automatic orientation correction of irregular chips by leveraging flow field disturbance and tilting structure to improve assembly yield: By utilizing the tilting feature of the chip's rear end and the disturbance effect of positioning protrusions on the fluid (local eddies or pressure gradients), under the combined action of fluid shear force and gravitational torque, chips with incorrect orientations are rotated and flipped, and continue to flow past the occupied points. They only fall into the fixed position when the orientation is correct and the hole positions match. This self-alignment and error prevention design based on a purely physical mechanism ensures high-precision orientation and high-yield assembly of irregular chips.

[0016] 3. It has an automatic recycling function for unassembled chips, which improves material utilization and process continuity: A recycling channel is set downstream of the carrier board. Chips that have not been fixed in the effective area can directly enter the recycling channel with the fluid and be transported back to the upstream inlet for the next round of self-assembly. At the same time, by adjusting the flow field parameters to set the flow rate threshold, it is ensured that the fixed chips are firmly locked while the unfixed chips continue to flow, thus ensuring the continuity and high throughput of the mass transfer process. Attached Figure Description

[0017] Figure 1 This is a front view of the chip to be transferred according to the present invention; Figure 2 This is a side view of the chip to be transferred according to the present invention; Figure 3 This is a top view of the chip to be transferred according to the present invention; Figure 4This is a schematic diagram of the installation of the chip to be transferred and the carrier board according to the present invention; Figure 5 This is a schematic diagram of the carrier plate of the present invention; Figure 6 This is a schematic diagram of the flow field correction of the chip to be transferred in this invention; Figure 7 This is a schematic diagram of the chip transfer device based on fluid self-assembly of the present invention.

[0018] In the diagram: 1. Small hole; 2. Large hole; 3. Carrier plate; 4. Large bump; 5. Small bump; 6. Flow field generator; 7. Fluid tank; 8. Recovery channel. Detailed Implementation

[0019] The present invention will now be further described.

[0020] like Figure 1 – Figure 7 As shown in Example 1, a chip transfer method based on fluid self-assembly includes the following steps: S1. A fluid tank 7 is provided, the fluid tank 7 contains a suspension for transferring chips, a carrier plate 3 is placed in the fluid tank 7, and the surface of the carrier plate 3 is arrayed with multiple sets of positioning protrusions, including large protrusions 4 and small protrusions 5. S2. A uniform and adjustable flow field is formed in the fluid tank 7 by the flow field generator 6, so that the chip to be transferred flows with the fluid above the carrier plate 3 in a preset direction; the chip to be transferred has a large hole 2 and two small holes 1, and the chip to be transferred is an irregularly shaped chip with a front end and a rear end, and the rear end of the chip to be transferred is raised relative to the front end. S3. The flow field drives the chip to be transferred through the positioning area on the carrier plate 3. When the raised part of the rear end of the chip to be transferred passes the large bump 4 and the small bump 5, under the combined action of fluid shear force and gravitational torque, the chip to be transferred adjusts its attitude and passes over the fixed chip to continue flowing downstream until the large hole 2 on the chip to be transferred matches the large bump 4 and the small hole 1 matches the small bump 5 and falls into the corresponding position to complete the fixation, or it passes over all the unmatched positioning bumps and enters the downstream recycling channel 8.

[0021] The specific process of attitude adjustment in step S3 includes: when the chip to be transferred flows over the large bump 4 or the small bump 5 with its rear end raised, the large bump 4 or the small bump 5 disturbs the fluid, forming a local eddy or pressure gradient zone; the raised rear end of the chip to be transferred is subjected to the lifting force or lateral force of the local eddy or pressure gradient zone, combined with the drag force of the mainstream fluid direction, causing the chip to be transferred to rotate and flip around its center of mass or front end fulcrum; when the chip to be transferred flips to a preset angle, the large hole 2 is fitted around the outer periphery of the large bump 4, and the small hole 1 is fitted around the outer periphery of the small bump 5, achieving self-locking fixation.

[0022] It also includes chip recycling and circulation steps: a recycling channel 8 is set at the downstream end of the carrier plate 3. Chips that have not been fixed on the carrier plate 3 are carried by the fluid and pass through the effective assembly area of ​​the carrier plate 3 directly into the recycling channel 8. The unassembled chips are collected through the recycling channel 8 and transported back to the upstream inlet of the fluid tank 7 for the next round of self-assembly transfer.

[0023] The flow field generator 6 can adjust the flow rate, viscosity or pulse frequency of the suspension and set the flow rate threshold so that the fluid drag force on the chip fixed on the large bump 4 and the small bump 5 is less than the mechanical interlocking force or adsorption force between it and the positioning bump, while the fluid drag force on the unfixed chip to be transferred is sufficient to overcome the frictional resistance between it and the surface of the carrier plate 3.

[0024] Example 2: A chip transfer device based on fluid self-assembly, used to implement the chip transfer method based on fluid self-assembly described in Example 1, comprising: Fluid tank 7: It has a cavity inside for fluid flow; Carrier plate 3: It is detachably set in the fluid tank 7. Multiple sets of positioning protrusions are arranged in an array on the upper surface of the carrier plate 3. The positioning protrusions include large protrusions 4 and small protrusions 5. Each positioning protrusion can cooperate with the large hole 2, small hole 1 and rear end protrusion on the irregularly shaped chip to be transferred to restrict the chip's degree of freedom. Flow field generator 6: Communicated with fluid tank 7, used to drive the suspension containing the chip to be transferred to form a uniform and adjustable flow field in fluid tank 7; Recovery channel 8 (prior art): Located at the downstream end of fluid tank 7, it is used to collect chips that failed to be assembled on carrier plate 3 and guide them back to upstream or external storage container.

[0025] The flow field generator 6 includes a pump body and a flow regulating valve, which are used to control the uniformity of the flow rate of the fluid in the fluid tank 7.

[0026] The top shapes of the large bump 4 and the small bump 5 are complementary to the inner wall contours of the large hole 2 and the small hole 1 on the chip to be transferred, respectively.

[0027] The heights of the large bump 4 and the small bump 5 are set as follows: when the chip to be transferred falls in with the correct posture, the main plane of the chip is parallel to or at a certain angle to the surface of the carrier board 3; when the chip to be transferred contacts with the wrong posture, the large bump 4 or the small bump 5 applies a reverse torque to the chip, causing it to bounce up and continue to move downstream with the fluid.

[0028] The chip to be transferred is designed in a streamlined shape, with a larger left side and a smaller right side, and its center of gravity is biased to the left. During the falling process, under the influence of the flow field force, the large hole 2 of the chip and the large protrusion 4 of the carrier plate 3 are most easily aligned. After the large hole 2 and the large protrusion 4 are aligned, there may be an angular positional deviation, which may cause the small protrusion 5 to be unable to be accurately positioned. Under the influence of the flow field force, the chip will continuously adjust its position, eventually completing the positioning of the three holes and three protrusions. The initial flow field velocity is relatively low, and the chip to be transferred falls to the left. Subsequently, the flow velocity is adjusted according to time, thereby adjusting the falling position of the chip to be transferred, achieving uniform landing point and improving the chip fixation efficiency.

Claims

1. A chip transfer method based on fluid self-assembly, characterized in that: Includes the following steps: S1. A fluid tank (7) is provided, the fluid tank (7) contains a suspension for transferring chips, a carrier plate (3) is placed in the fluid tank (7), and the surface of the carrier plate (3) is arrayed with multiple sets of positioning protrusions, including large protrusions (4) and small protrusions (5). S2. A uniform and adjustable flow field is formed in the fluid tank (7) by the flow field generator (6), so that the chip to be transferred flows with the fluid above the carrier plate (3) in a preset direction; the chip to be transferred is provided with a large hole (2) and a small hole (1), and the chip to be transferred is an irregularly shaped chip with a front end and a rear end, and the rear end of the chip to be transferred is raised relative to the front end; S3. The flow field drives the chip to be transferred to flow through the positioning area on the carrier plate (3). When the rear end of the chip to be transferred is raised and passes the large bump (4) and the small bump (5), under the combined action of fluid shear force and gravitational torque, the chip to be transferred adjusts its posture and passes over the fixed chip to continue flowing downstream until the large hole (2) on the chip to be transferred matches the large bump (4) and the small hole (1) matches the small bump (5) and falls into the corresponding position to complete the fixation, or passes over all unmatched positioning bumps and enters the downstream recycling channel (8).

2. The chip transfer method based on fluid self-assembly according to claim 1, characterized in that: The specific process of attitude adjustment in step S3 includes: when the chip to be transferred flows over the large bump (4) or small bump (5) with its rear end raised, the large bump (4) or small bump (5) disturbs the fluid and forms a local eddy or pressure gradient zone; the raised part of the rear end of the chip to be transferred is subjected to the lifting force or lateral force of the local eddy or pressure gradient zone, and with the drag force of the mainstream fluid direction, the chip to be transferred rotates and flips around its center of mass or front end fulcrum; when the chip to be transferred flips to a preset angle, the large hole (2) is fitted on the outer periphery of the large bump (4), and the small hole (1) is fitted on the outer periphery of the small bump (5) to achieve self-locking fixation.

3. The chip transfer method based on fluid self-assembly according to claim 1, characterized in that: It also includes chip recycling and circulation steps: a recycling channel (8) is set at the downstream end of the carrier (3). The chips to be transferred that have not been fixed on the carrier (3) are carried by the fluid and pass over the effective assembly area of ​​the carrier (3) directly into the recycling channel (8). The unassembled chips are collected through the recycling channel (8) and transported back to the upstream inlet of the fluid tank (7) for the next round of self-assembly transfer.

4. The chip transfer method based on fluid self-assembly according to claim 1, characterized in that: The flow field generator (6) can adjust the flow rate, viscosity or pulse frequency of the suspension and set the flow rate threshold so that the fluid drag force on the chip fixed on the large bump (4) and the small bump (5) is less than the mechanical interlocking force or adsorption force between it and the positioning bump, while the fluid drag force on the unfixed chip to be transferred is sufficient to overcome the frictional resistance between it and the surface of the carrier plate (3).

5. A chip transfer apparatus based on fluid self-assembly, used to implement the chip transfer method based on fluid self-assembly as described in any one of claims 1 to 4, characterized in that, include: Fluid tank (7): Its interior has a cavity for fluid flow; Carrier plate (3): It is detachably set in the fluid tank (7). Multiple sets of positioning protrusions are arranged in an array on the upper surface of the carrier plate (3). The positioning protrusions include large protrusions (4) and small protrusions (5). Each positioning protrusion can cooperate with the large hole (2), small hole (1) and rear end protrusion on the irregularly shaped chip to be transferred, so as to restrict the chip's degree of freedom. Flow field generator (6): connected to the fluid tank (7), used to drive the suspension containing the chip to be transferred to form a uniform and adjustable flow field in the fluid tank (7); Recovery channel (8): Located at the downstream end of the fluid tank (7), it is used to collect chips that failed to be assembled on the carrier plate (3) and guide them back to the upstream or external liquid storage container.

6. The chip transfer device based on fluid self-assembly according to claim 5, characterized in that: The flow field generator (6) includes a pump body and a flow regulating valve, which are used to control the uniformity of the flow rate of the fluid in the fluid tank (7).

7. The chip transfer device based on fluid self-assembly according to claim 5, characterized in that: The top shapes of the large bump (4) and the small bump (5) are complementary to the inner wall contours of the large hole (2) and the small hole (1) on the chip to be transferred, respectively.

8. The chip transfer device based on fluid self-assembly according to claim 5, characterized in that: The heights of the large bump (4) and the small bump (5) are set as follows: when the chip to be transferred falls in the correct posture, the main body plane of the chip is parallel to or at a certain angle to the surface of the carrier board (3); when the chip to be transferred contacts in the wrong posture, the large bump (4) or the small bump (5) applies a reverse torque to the chip, causing it to bounce up and continue to move downstream with the fluid.

Images