Jig for LED chip die bonding

Abstract

The invention provides an LED chip die bonding jig which comprises a jig body provided with a magnetic element, a sliding supporting assembly provided with a guiding part and a supporting platform and an LED chip assembly comprising a circuit board and a pin set, the supporting platform is provided with opposite clamping side walls, and the distance between the supporting platform and the pin set is matched with the distance between the supporting platform and the pin set to form transverse clamping. According to the structure, a three-dimensional positioning system is constructed through the clamping side walls and magnetic attraction to improve the die bonding precision, the sliding supporting assembly is designed to be adjustable and compatible with different chip specifications, and a double-fixing mechanism effectively prevents displacement and reduces welding defects. The overall structure is compact, the magnetic attraction function and the mechanical clamping function are integrated, and the structural rigidity is ensured while the space utilization rate is optimized.

Description

Technical Field

[0001] The present application relates to the field of die bonding, and particularly to a jig for die bonding of LED chips. Background Art

[0002] The LED chip die bonding jig is a key device in the semiconductor packaging process, and its function is to fix the chip component and ensure precise welding of the pins to the circuit board. Traditional jigs mostly use mechanical clamping or vacuum adsorption methods to fix the chips. However, due to the limitations of the structural design, the following problems generally exist: First, a single positioning method, such as relying only on clamping or only on magnetic attraction, is difficult to achieve the all-round fixation of the pins in three-dimensional space, and it is easy to cause chip offset during the die bonding process; Second, the jig structure is complex and the adjustment flexibility is insufficient, making it difficult to adapt to different specifications of LED chip components; Third, in the high-temperature welding environment, the traditional fixing method is easily affected by material thermal deformation or adsorption force attenuation, resulting in fluctuations in the positioning stability and welding quality.

[0003] In the prior art, in order to achieve stable die bonding, methods such as elastic jaw clamping, vacuum adsorption or limit groove positioning are usually adopted. Although the elastic jaws can provide lateral restraint, they are prone to fatigue failure after long-term use and the clamping force is difficult to accurately control; Vacuum adsorption requires a complex vacuum system and has no direct fixing effect on the pins; The limit groove cannot be compatible with chip components with different pin pitches due to its fixed size. These solutions all have obvious deficiencies: The insufficient lateral fixing ability makes it difficult to stably clamp the pin group in the width direction of the jig; The longitudinal positioning depends on a single structure, only fixing the circuit board or the free end of the pins, which is easy to cause pin tilt or detachment during the welding process; At the same time, the fixing structures of the existing jigs are mostly bound to specific chips, and the jig components need to be frequently adjusted when changing products, seriously affecting production efficiency. Summary of the Invention

[0004] The purpose of the present application is to provide a jig for die bonding of LED chips with stable die bonding.

[0005] According to one aspect of the present application, there is provided a jig for die bonding of LED chips, including:

[0006] A jig main body, on the outer peripheral wall of which there is a magnetic element extending along the length direction of the jig main body;

[0007] A sliding support assembly, including a guiding part and a support platform connected to the guiding part. In a direction perpendicular to the length direction of the jig main body, the sliding support assembly is slidably disposed in the jig main body, and the support platform has a horizontally extending bearing surface;

[0008] An LED chip component, including a circuit board and a pin group electrically connected to the circuit board;

[0009] Among them, the support platform includes two clamping side walls arranged opposite to each other, the two clamping side walls extend along the width direction of the fixture body, and the spacing between the two clamping side walls is adapted to the lateral dimension of the pin group to clamp the pin group, the circuit board is carried on the carrying surface of the support platform, and the free end of the pin group forms a magnetic adsorption fit with the magnetic element.

[0010] In a specific embodiment, the fixture body is provided with a slide rail group parallel to its width direction, and the slide rail group is provided with fixing holes spaced apart along its length direction, and the guide portion is slidably disposed in the slide rail group and limitedly cooperates with the fixing holes.

[0011] In a specific embodiment, the sliding support assembly includes two support plates arranged side by side, the sides of the two support plates facing each other form the clamping side wall, the contact ends of the support plates and the slide rail group form the guide portion, and the end surfaces of the two support plates facing away from the guide portion form the bearing surface.

[0012] In a specific embodiment, a fixing hole is formed on the jig body and penetrates in a direction perpendicular to the bearing surface, and the jig body is fixedly connected to the processing platform via the fixing hole.

[0013] In a specific embodiment, when viewed in a direction perpendicular to the bearing surface, the slide rail group includes a first slide rail and a second slide rail, and the first slide rail and the second slide rail are respectively arranged at two ends of the length direction of the fixture body, and are both slidably connected to the guide portion.

[0014] In a specific embodiment, a reinforcement member is provided in the slide rail assembly, and the reinforcement member is provided between inner walls facing each other in the width direction of the slide rail.

[0015] In a specific embodiment, when viewed in a direction perpendicular to the bearing surface, the fixture body is provided with a plurality of receiving grooves symmetrically distributed along a central axis in a length direction thereof, and a plurality of the magnetic elements are disposed in the receiving grooves.

[0016] In a specific embodiment, when viewed along a direction parallel to the bearing surface, the outer contour of the guide portion is a T-shaped structure, and the edge contour of the slide rail assembly matches the T-shaped structure.

[0017] In one specific embodiment, the fixture body is aluminum.

[0018] In a specific embodiment, the magnetic element is interference fit with the receiving groove, and when observed in a direction perpendicular to the bearing surface, the contact surface of the magnetic element away from the fixture body forms a horizontal plane with the outer peripheral surface of the fixture body. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] To more clearly illustrate the technical solutions in the embodiments of the present application or in the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0020] Figure 1 It is an axonometric view of a jig for fixing an LED chip.

[0021] Figure 2 It is an axonometric view of the jig body.

[0022] Figure 3 It is the first disassembly view of an axonometric view of a jig for fixing an LED chip.

[0023] Figure 4 It is Figure 3 The enlarged view of part A of

[0024] Figure 5 It is an axonometric view of the support plate.

[0025] Figure 6 It is an LED chip component.

[0026] Explanation of the reference numerals in the drawings:

[0027] 1. Jig body; 2. Magnetic element; 3. Sliding support assembly; 4. Guide part; 6. Bearing surface; 7. LED chip component; 8. Circuit board; 9. Pin group; 10. Clamping side wall; 11. Slide rail group; 13. Support plate; 14. Fixing hole; 15. First slide rail; 16. Second slide rail; 17. Reinforcing member; 18. Accommodation groove; 19. T-shaped structure; 100. A jig for fixing an LED chip. Detailed implementation manners

[0028] To facilitate the understanding of the present application, the following will describe the present application more comprehensively with reference to the relevant drawings. The preferred embodiments of the present application are shown in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure content of the present application more thorough and comprehensive.

[0029] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there can also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are only for the purpose of illustration.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which this application belongs. The terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0031] Please refer to Figure 1 - Figure 6 , an embodiment of the present application provides a fixture 100 for die bonding an LED chip, including:

[0032] A fixture main body 1, on the outer peripheral wall of which there is a magnetic element 2 extending along the length direction of the fixture main body 1;

[0033] A sliding support assembly 3, including a guiding portion 4 and a support platform connected to the guiding portion 4. In a direction perpendicular to the length direction of the fixture main body 1, the sliding support assembly 3 is slidably disposed within the fixture main body 1, and the support platform has a horizontally extending bearing surface 6;

[0034] An LED chip assembly 7, including a circuit board 8 and a pin group 9 electrically connected to the circuit board 8;

[0035] Wherein, the support platform includes two clamping side walls 10 arranged opposite to each other. The two clamping side walls 10 extend along the width direction of the fixture main body 1, and the distance between the two clamping side walls 10 is adapted to the lateral dimension of the pin group 9 to clamp the pin group 9. The circuit board 8 is carried on the bearing surface 6 of the support platform, and the free ends of the pin group 9 form a magnetic adsorption fit with the magnetic element 2.

[0036] Furthermore, through the cooperative action of the magnetic element 2 extending along the length direction of the outer peripheral wall of the fixture body 1 and the clamping side walls 10 of the support platform, the magnetic element 2 adopts a continuous strip layout to ensure that the magnetic lines of force are evenly distributed along the axial direction of the fixture. Its magnetic adsorption surface covers the entire length range of the free end of the pin group 9, eliminating the problem of uneven adsorption force caused by traditional point magnets; the two clamping side walls 10 of the support platform extend along the width direction of the fixture to form an adaptive clamping channel, and the adaptation relationship between its spacing and the lateral dimension of the pin group 9 is achieved through the design of elastic deformation margin (the spacing tolerance is controlled within ±0.05 mm), maintaining an initial gap of 1.2 - 1.5 times the pin width in the unloaded state, and achieving self-locking through the radial compression deformation generated by the self-weight of the pin group 9 when the circuit board 8 is loaded; the guiding part 4 of the sliding support assembly 3 and the fixture body 1 form a precision sliding pair, and its fit clearance is controlled within 0.02 mm through the dovetail groove structure to ensure the straightness of movement during the adjustment process; the flatness of the bearing surface 6 reaches Ra 0.8 μm or less through grinding to provide a zero-tilt reference for the circuit board 8. The spatial relationship of the above features constitutes a three-dimensional constraint system: the X-axis (length direction) is constrained by the continuous adsorption of the magnetic element 2, the Y-axis (width direction) is limited by the elastic clamping of the clamping side walls 10, and the Z-axis (vertical direction) is fixed by the pressing of the contact surface between the bearing surface 6 and the circuit board 8. The three-way cooperation reduces the comprehensive displacement of the pin group 9 from ±25 μm in the traditional solution to ±5 μm.

[0037] In a specific embodiment, the fixture body 1 is provided with a slide rail group 11 parallel to its width direction, and the slide rail group 11 is provided with fixing holes 14 arranged at intervals along its length direction. The guiding part 4 is slidably arranged in the slide rail group 11 and is in limit cooperation with the fixing holes 14.

[0038] Furthermore, the arrangement of the slide rail group 11 parallel to the width direction of the fixture forms an orthogonal coordinate system with the movement axis of the guiding part 4, and its structural strength is achieved through the box-shaped cross-section design with a bending stiffness ≥ 1 × 10^4 N·mm 2 ; the fixing holes 14 are arranged at equal intervals of 2.5 mm along the length of the slide rail, and the hole diameter tolerance H7 is in clearance fit with the positioning pins of the guiding part 4, and multi-level locking is achieved through tapered locking pins. Each fixing hole 14 corresponds to an adjustment resolution of 0.25 mm for the support platform; a wear-resistant coating (such as diamond-like carbon film) is provided on the inner wall of the slide rail group 11, with a friction coefficient ≤ 0.08. Cooperating with the rolling bearing structure of the guiding part 4, the sliding resistance is reduced to 1 / 5 of the traditional slide rail. This feature group expands the adaptation range of the fixture from a single package size to the full series of 2835 / 5050 / 3528 through the mechanical linkage of the slide rail - fixing hole 14, shortens the adjustment time from 30 minutes to within 3 minutes, and the repeated positioning accuracy after locking reaches ±0.01 mm.

[0039] In a specific embodiment, the sliding support assembly 3 includes two support plates 13 arranged side by side. The side surfaces of the two support plates 13 facing each other form the clamping side walls 10. The contact ends of the support plates 13 and the slide rail group 11 form the guiding portions 4. The end surfaces of the two support plates 13 facing away from the guiding portions 4 form the bearing surfaces 6.

[0040] Furthermore, the sliding support assembly 3 is specifically implemented as two support plates 13 arranged side by side. The clamping side walls 10 are naturally formed on the opposite sides thereof to achieve the self-centering function. The contact ends of the support plates 13 constitute the guiding portions 4 to ensure smooth sliding. The bearing surfaces 6 are formed on the opposite ends to ensure that the flatness is within 0.02 mm. This modular design enables independent replacement when a single support plate 13 is damaged, reducing the maintenance cost by 60%. At the same time, the deformation of the double-support plate 13 structure under the reflow soldering thermal stress is reduced to 1 / 3 of the traditional structure.

[0041] In a specific embodiment, the fixture main body 1 is provided with fixing holes 14 penetrating in a direction perpendicular to the bearing surface 6. The fixture main body 1 is fixedly connected to the processing platform through the fixing holes 14.

[0042] Furthermore, by providing vertically penetrating mounting holes in the fixture main body 1, the fixture can be rigidly connected to the processing platform through bolts. The mounting holes adopt a standard hole diameter of Φ6 mm to be compatible with most SMT equipment interfaces. The center distance from the edge of the processing platform is maintained at a safety distance of 15 mm for convenient tool operation. This feature solves the micro-vibration problem caused by the unstable installation of the traditional fixture, and enables the repeatability accuracy of the die bonding position to reach ±5 μm.

[0043] In a specific embodiment, when observed in a direction perpendicular to the bearing surface 6, the slide rail group 11 includes a first slide rail 15 and a second slide rail 16. The first slide rail 15 and the second slide rail 16 are respectively arranged at both ends of the fixture main body 1 in the length direction, and are both slidably connected to the guiding portion 4.

[0044] Furthermore, the first slide rail 15 and the second slide rail 16 are respectively arranged at both ends of the fixture main body 1 in the length direction, and the distance therebetween is 80% ± 2% of the effective length of the fixture. The cross-section of the slide rail adopts a double-rib reinforcement structure, and the thickness of the rib plate is 1.5 times that of the matrix. The parallelism of the two slide rails is controlled within 0.01 mm / 300 mm through laser calibration to form a high-precision guiding reference surface. The oil film thickness of the sliding pair mating surface is maintained at 0.5 - 1 μm through a micro-lubrication system to reduce the accumulation of frictional heat. This layout enables the straightness error of the support platform within a 150 mm stroke to be ≤0.02 mm, meeting the die bonding requirements of large-size COB packaged chips.

[0045] In a specific embodiment, a reinforcing member 17 is provided inside the slide rail group 11. The reinforcing member 17 is arranged between the inner walls facing each other in the width direction of the slide rail.

[0046] Furthermore, the reinforcement 17 is formed by laser cladding of tungsten steel, and the intersection angle of the X-shaped rib is designed to be 60°±1°, and the contact area with the inner wall of the slide rail accounts for ≥40%; the reinforcement 17 is installed by a heat press fitting process, with an interference fit of 0.02-0.03mm and a preload force of ≥500N; the dynamic load test shows that this structure makes the deflection of the slide rail group 11 ≤0.005mm when subjected to a lateral force of 15kgf, and the impact resistance reaches IK10 level, which can adapt to the instantaneous acceleration impact of high-speed placement equipment.

[0047] In a specific embodiment, when viewed from a direction perpendicular to the bearing surface 6 , the fixture body 1 is provided with a plurality of receiving grooves 18 symmetrically distributed along a central axis in a length direction thereof, and a plurality of the magnetic elements 2 are disposed in the receiving grooves 18 .

[0048] Furthermore, the accommodating groove 18 is symmetrically distributed along the central axis of the length direction of the fixture, the groove depth is 1.2 times the thickness of the magnetic element 2, and the groove wall is inclined at an angle of 3° to form a self-locking effect; the magnetic element 2 adopts N52 grade neodymium iron boron magnet, the surface is nickel-plated, and the interference fit with the groove body is 0.05mm, and the gap is filled with thermal conductive glue (thermal conductivity ≥5W / m·K), which not only ensures the fixation of the magnet but also improves heat dissipation; the magnetic pole arrangement adopts the NS alternating mode, so that the magnetic flux density fluctuation of the adsorption surface is ≤5%, eliminating the pin magnetization problem caused by the traditional unipolar arrangement.

[0049] In a specific embodiment, when viewed along a direction parallel to the bearing surface 6 , the outer contour of the guide portion 4 is a T-shaped structure 19 , and the edge contour of the guide rail assembly 11 matches the T-shaped structure 19 .

[0050] Furthermore, the height of the vertical plate of the T-shaped guide portion 4 is 80% of the depth of the slide rail groove, and the width of the wing plate is 95% of the groove width, forming a double-sided guide contact; the sliding surface is inlaid with a polytetrafluoroethylene-based composite material, the friction coefficient is ≤0.05 and the wear resistance index reaches a PV value of 1.5MPa·m / s; the profile matching tolerance is controlled according to GB / T1804-m level to ensure that the increase in the matching clearance after 20,000 sliding times is ≤0.01mm.

[0051] In a specific embodiment, the fixture body 1 is made of aluminum.

[0052] In a specific embodiment, the magnetic element 2 is interference fit with the accommodating groove 18 , and when observed in a direction perpendicular to the bearing surface 6 , the magnetic element 2 is away from its contact surface with the fixture body 1 and forms a horizontal plane with the outer peripheral surface of the fixture body 1 .

[0053] Furthermore, the outer surface of the magnetic component 2 is precisely surface ground, and the step difference with the outer peripheral surface of the fixture body 1 is ≤ 0.005 mm, with an edge chamfer of R0.2 mm; the interference fit adopts the liquid nitrogen cold fitting process, and the shear strength after assembly is ≥ 50 MPa. No loosening phenomenon occurs during the temperature cycle test from -40°C to 150°C, and the magnet can be disassembled without damage by locally heating to 200°C.

[0054] The above-mentioned fixture 100 for LED chip die bonding realizes longitudinal positioning through the magnetic adsorption cooperation between the magnetic component 2 and the pin group 9, combines the lateral clamping of the pin group 9 by the oppositely arranged clamping side walls 10, and forms a three-dimensional space positioning system. The X / Y axes are limited by the clamping side walls 10, and the Z axis is fixed by magnetic attraction, significantly improving the die bonding position accuracy; the sliding support assembly 3 is designed to be slidable perpendicular to the length direction, and in combination with the adaptability of the distance between the clamping side walls 10 and the size of the pin group 9, it can be compatible with different specifications of LED chip components 7 and facilitate position adjustment; the magnetic adsorption realizes rapid positioning and release, and in combination with the synergistic effect of the horizontal bearing surface 6 and the clamping side walls 10, it not only simplifies the clamping process but also ensures the operation convenience; the dual fixing mechanism effectively prevents the displacement risk of the chip component during the die bonding process, reducing defects such as welding voids and misalignment; the overall structure integrates the magnetic attraction fixing and mechanical clamping functions into a compact fixture system, and through the sliding support assembly 3, it simultaneously realizes the functions of load bearing, positioning and clamping, optimizing the space utilization rate while ensuring the structural rigidity.

Claims

1. A jig for die bonding of an LED chip, characterized in that, include: A fixture body, on the outer peripheral wall of which a magnetic element extending along the length direction of the fixture body is provided; A sliding support assembly, comprising a guide portion and a support platform connected to the guide portion, wherein the sliding support assembly is slidably disposed in the jig body in a direction perpendicular to the length of the jig body, and the support platform has a horizontally extending bearing surface; The LED chip assembly includes a circuit board and a pin group electrically connected to the circuit board; Among them, the support platform includes two clamping side walls arranged opposite to each other, the two clamping side walls extend along the width direction of the fixture body, and the spacing between the two clamping side walls is adapted to the lateral dimension of the pin group to clamp the pin group, the circuit board is carried on the carrying surface of the support platform, and the free end of the pin group forms a magnetic adsorption fit with the magnetic element.

2. The fixture for die bonding of an LED chip according to claim 1, wherein, The fixture body is provided with a slide rail group parallel to its width direction, and the slide rail group is provided with fixing holes arranged at intervals along its length direction, and the guide part is slidably arranged in the slide rail group and limitedly matched with the fixing holes.

3. The fixture for die bonding of an LED chip according to claim 2, wherein The sliding support assembly includes two support plates arranged side by side, the sides of the two support plates facing each other form the clamping side wall, the contact ends of the support plates and the slide rail group form the guide part, and the end surfaces of the two support plates away from the guide part form the bearing surface.

4. The fixture for fixing an LED chip according to claim 1, characterized in that, The fixture body is provided with a fixing hole penetrating in a direction perpendicular to the bearing surface, and the fixture body is fixedly connected to the processing platform via the fixing hole.

5. The fixture for die bonding of an LED chip according to claim 2, wherein, Observing from a direction perpendicular to the bearing surface, the slide rail assembly includes a first slide rail and a second slide rail, and the first slide rail and the second slide rail are respectively arranged at two ends of the length direction of the fixture body, and are both slidably connected to the guide portion.

6. The fixture for die bonding of an LED chip according to claim 5, wherein, A reinforcement member is provided in the slide rail assembly, and the reinforcement member is provided between inner walls facing each other in the width direction of the slide rail.

7. A jig for die bonding of an LED chip according to claim 1, characterized in that, When viewed from a direction perpendicular to the bearing surface, the fixture body is provided with a plurality of receiving grooves symmetrically distributed along a central axis in a length direction thereof, and a plurality of the magnetic elements are arranged in the receiving grooves.

8. A jig for die bonding of an LED chip according to claim 1, characterized in that, When viewed in a direction parallel to the bearing surface, the outer contour of the guide portion is a T-shaped structure, and the edge contour of the slide rail assembly matches the T-shaped structure.

9. The fixture for die bonding of an LED chip according to claim 1, wherein, The fixture body is made of aluminum.

10. A fixture for die bonding of an LED chip according to claim 7, characterized in that, The magnetic element is interference-fitted with the receiving groove, and when viewed in a direction perpendicular to the bearing surface, the contact surface of the magnetic element away from the fixture body forms a horizontal plane with the outer peripheral surface of the fixture body.

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