Auxiliary jig for lead frame

Abstract

The utility model provides an auxiliary jig for a lead frame, and relates to the technical field of semiconductor packaging. The auxiliary jig is used for fixedly installing the lead frame, the lead frame comprises a plurality of bonding pads arranged at intervals, the auxiliary jig comprises a cover plate and a bottom plate, the cover plate comprises a plurality of limiting holes, each limiting hole corresponds to one bonding pad, the cover plate is made of magnetic materials, the bottom plate is located at the bottom of the cover plate, and a limiting groove is formed in the top of the bottom plate. The limiting groove is used for limiting the lead frame, and the bottom plate is connected with the cover plate in a magnetic attraction mode, so that the lead frame is fixedly installed between the cover plate and the bottom plate. According to the utility model, the top of the bottom plate is provided with the limiting groove, and the bottom plate and the cover plate are connected in a magnetic attraction manner, so that the lead frame is fixed in the limiting groove, and the lead frame is further limited by the bottom plate and the cover plate, thereby realizing the fixation of the lead frame by using a simple structure, and ensuring the flatness of the lead frame.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor packaging technology, specifically to an auxiliary fixture for lead frames. Background Technology

[0002] Leadframes play a crucial role in semiconductor packaging and electronic component manufacturing. As a fundamental material for integrated circuit and device molding packaging, it primarily consists of chip pads and leads. Chip pads provide mechanical support for the chip during packaging, ensuring its stability during subsequent processing and use. In circuit board fabrication, leadframes also help engineers accurately and efficiently arrange and connect various components, resulting in a more compact component layout, reduced circuit board space, and improved integration and performance.

[0003] With the rapid development of electronic information technology, the integration level of semiconductor devices and integrated circuits is becoming increasingly higher, and the requirements for packaging technology are also becoming more stringent. Because the lead frame itself has a sheet-like structure with extremely small thickness, it is easily deformed under stress during the packaging process, which affects the flatness of the lead frame and thus the packaging effect.

[0004] In the prior art, two positioning plates and an adjustment device are used to fix the lead frame. However, the structure of the adjustment device is relatively complex and the operation is cumbersome, which usually affects the efficiency of semiconductor packaging and increases packaging costs. Utility Model Content

[0005] One objective of this invention is to provide an auxiliary fixture for lead frame, which solves the technical problem of complex and cumbersome operation of the existing lead frame flatness adjustment device.

[0006] Another objective of this invention is to improve the ease of use of auxiliary fixtures.

[0007] According to the purpose of this utility model, this utility model provides an auxiliary fixture for a lead frame, used for fixing and installing the lead frame, the lead frame including a plurality of spaced-apart pads, and the auxiliary fixture including:

[0008] The cover plate includes multiple limiting holes, each of which corresponds to one of the pads, and the cover plate is made of magnetic material.

[0009] A base plate is located at the bottom of the cover plate, and a limiting groove is provided on the top of the base plate. The limiting groove is used to limit the lead frame. The base plate is configured to be connected to the cover plate by magnetic attraction, so that the lead frame is fixedly installed between the cover plate and the base plate.

[0010] Optionally, the base plate is further provided with at least one weight-reducing hole, which is located at the bottom of the base plate.

[0011] Optionally, the number of weight-reducing holes is multiple, and the multiple weight-reducing holes are evenly spaced at the bottom of the base plate.

[0012] Optionally, the base plate is further provided with two clearance grooves, which are located at opposite ends of the base plate.

[0013] Optionally, the end of the relief groove near the limiting groove is provided with a weight reduction hole.

[0014] Optionally, the limiting groove is flush with the top of the lead frame.

[0015] Optionally, the auxiliary fixture further includes:

[0016] At least one magnet is located at the bottom of the base plate, and the magnet is detachably connected to the base plate.

[0017] Optionally, the number of magnets is multiple, and the multiple magnets are evenly spaced at the bottom of the base plate.

[0018] The auxiliary fixture of this utility model sets a limiting groove on the top of the base plate and connects the base plate and the cover plate by magnetic attraction. This allows the lead frame to be fixed in the limiting groove while the base plate and the cover plate further limit the lead frame. Thus, the lead frame is fixed with a simple auxiliary fixture to ensure the flatness of the lead frame and prevent deformation of the lead frame under stress during welding.

[0019] Furthermore, the base plate of this utility model is also provided with two clearance grooves. The two clearance grooves are located at opposite ends of the base plate and on opposite sides in the width direction. The two clearance grooves are set to be recessed from the side of the base plate toward the center of the base plate, so as to facilitate the removal and placement of the cover plate and the lead frame, thereby improving the ease of use of the auxiliary fixture.

[0020] The above description is only an overview of the technical solution of this utility model. In order to better understand the technical means of this utility model and to implement it in accordance with the contents of the specification, the preferred embodiments of this utility model are described in detail below with reference to the accompanying drawings. Attached Figure Description

[0021] The following sections will describe some specific embodiments of the present invention in a detailed manner by way of example and not limitation, with reference to the accompanying drawings. The same reference numerals in the drawings denote the same or similar parts or components. Those skilled in the art should understand that these drawings are not necessarily drawn to scale. In the drawings:

[0022] Figure 1This is a schematic structural diagram of an auxiliary fixture according to an embodiment of the present utility model;

[0023] Figure 2 This is a schematic structural diagram of a cover plate according to an embodiment of the present utility model;

[0024] Figure 3 This is a schematic structural diagram of the base plate according to an embodiment of the present utility model;

[0025] Figure 4 This is a schematic bottom view of the base plate according to an embodiment of the present utility model;

[0026] Figure 5 This is a schematic installation diagram of a magnet and a base plate according to an embodiment of the present invention.

[0027] Figure label:

[0028] 100-Auxiliary fixture, 10-Cover plate, 11-Limiting hole, 20-Base plate, 21-Limiting groove, 22-Weight reduction hole, 23-Leaning groove, 24-First positioning hole, 25-Second positioning hole, 30-Magnet. Detailed Implementation

[0029] The specific embodiments of this utility model will be described in further detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate this utility model, but are not intended to limit its scope.

[0030] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, it should be noted that, for ease of description, only the parts relevant to this application are shown in the accompanying drawings, not the entire structure. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this application.

[0031] The terms “comprising” and “having”, and any variations thereof, used in this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the steps or units listed, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such process, method, product, or apparatus.

[0032] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0033] Figure 1 This is a schematic structural diagram of an auxiliary fixture according to an embodiment of the present invention. Figure 2 This is a schematic structural diagram of a cover plate according to an embodiment of the present invention. Figure 3 This is a schematic structural diagram of the base plate according to an embodiment of the present utility model. Figure 4 This is a schematic bottom view of the base plate according to an embodiment of the present invention. Figure 5 This is a schematic installation diagram of a magnet and a base plate according to an embodiment of the present invention.

[0034] like Figure 1 As shown, this utility model provides an auxiliary fixture 100 for a lead frame. The auxiliary fixture 100 is used to fix and install the lead frame. The lead frame includes multiple spaced-apart pads for soldering electronic components. Here, the electronic components can be chips, surface mount resistors, surface mount capacitors, or other packaged electronic components.

[0035] In certain applications, it is necessary to apply adhesive and solder electronic components onto multiple pads of a leadframe with a large surface area and thin thickness, while ensuring the flatness of the leadframe. This requires specifying requirements for the leadframe's thickness and flatness. For example, a leadframe with a length of 270mm, a width of 90mm, a thickness of 0.254mm, and made of copper is required. Based on this requirement, this invention provides a specially designed auxiliary fixture 100 for the leadframe and offers the following embodiments.

[0036] like Figure 1 As shown, in this embodiment, the auxiliary fixture 100 includes a cover plate 10 and a base plate 20. The cover plate 10 includes multiple limiting holes 11, each corresponding to a solder pad. The cover plate 10 is made of magnetic material. The base plate 20 is located at the bottom of the cover plate 10, and a limiting groove 21 is provided at the top of the base plate 20. The limiting groove 21 is used to limit the lead frame. The base plate 20 is configured to be connected to the cover plate 10 by magnetic attraction, so that the lead frame is fixedly installed between the cover plate 10 and the base plate 20. Here, the size of the cover plate 10 is the same as the size of the base plate 20. In other embodiments, the size of the cover plate 10 is larger than the size of the base plate 20.

[0037] like Figure 3As shown, in this embodiment, by setting a limiting groove 21 on the top of the base plate 20 and connecting the base plate 20 and the cover plate 10 by magnetic attraction, the lead frame is fixed in the limiting groove 21, while the base plate 20 and the cover plate 10 further limit the lead frame. Thus, the lead frame is fixed by using a simple auxiliary fixture 100 to ensure the flatness of the lead frame and avoid deformation of the lead frame under stress during welding.

[0038] In this embodiment, the bottom of the lead frame is attached to the bottom of the limiting groove 21, and the top of the lead frame is attached to the bottom of the cover plate 10. The cover plate 10 is provided with a plurality of limiting holes 11 corresponding to the solder pads in the lead frame, so as to ensure the flatness of the lead frame and the soldering of the lead frame to the electronic components, and avoid affecting the normal use of the lead frame.

[0039] In this embodiment, since the base plate 20 has magnetic attraction to the cover plate 10, while the base plate 20 attracts the cover plate 10 to fix the lead frame, the magnetic force of the base plate 20 exerts a downward pulling force on the cover plate 10, so that the cover plate 10 exerts a downward pressure on the lead frame, thereby further improving the flatness of the lead frame.

[0040] like Figure 4 As shown, in a further embodiment, the base plate 20 is also provided with at least one weight-reducing hole 22, which is located at the bottom of the base plate 20. Specifically, the weight-reducing hole 22 is recessed from the bottom of the base plate 20 toward the top of the base plate 20, and the depth of the weight-reducing hole 22 is less than the thickness of the base plate 20, so as to reduce the weight of the base plate 20 and reduce the manufacturing cost of the base plate 20. In this embodiment, the number of weight-reducing holes 22 can be one or more. Here, the weight-reducing hole 22 can be rectangular, square, or circular.

[0041] In this embodiment, there is one weight-reducing hole 22. The weight-reducing hole 22 is set at the bottom of the base plate 20 to facilitate the stamping and forming of the weight-reducing hole 22 of the base plate 20. This avoids the increase in the preparation steps of the base plate 20 when multiple weight-reducing holes 22 are set at the bottom of the base plate 20, thereby reducing the preparation cost of the base plate 20.

[0042] In a further embodiment, there are multiple weight-reducing holes 22, which are evenly spaced at the bottom of the base plate 20. In this embodiment, the multiple weight-reducing holes 22 are evenly spaced at the bottom of the base plate 20 to ensure a uniform weight distribution of the auxiliary fixture 100, thereby ensuring the uniformity of the weight of the auxiliary fixture 100 on which the lead frame is mounted, and thus avoiding the uneven weight distribution of the base plate 20 from affecting the flatness of the lead frame.

[0043] like Figure 3As shown, in a further embodiment, the base plate 20 is also provided with two clearance grooves 23, which are located at opposite ends of the base plate 20. In this embodiment, the top surface of the base plate 20 is rectangular, and the two clearance grooves 23 are located on opposite sides in the width direction. The two clearance grooves 23 are configured to be recessed from the side of the base plate 20 toward the center of the base plate 20, so as to facilitate the placement and removal of the cover plate 10 and the lead frame, thereby improving the ease of use of the auxiliary fixture 100.

[0044] In a further embodiment, a weight-reducing hole 22 is provided at one end of the relief groove 23 near the limiting groove 21. In this embodiment, each relief groove 23 has a weight-reducing hole 22 on its periphery. The weight-reducing hole 22 is recessed from the top surface of the base plate 20 toward the bottom surface of the base plate 20. The weight-reducing hole 22 further reduces the weight of the base plate 20. At the same time, the weight-reducing hole 22 on the periphery of the relief groove 23 increases the contact area between the mechanism for gripping the cover plate 10 and the lead frame and the cover plate 10 or the lead frame, thereby improving the stability of picking up and placing the cover plate 10 and the lead frame.

[0045] In a further embodiment, the limiting groove 21 is flush with the top of the lead frame. In this embodiment, the depth of the limiting groove 21 is the same as the thickness of the lead frame, so that when the lead frame is installed in the auxiliary fixture 100, the bottom of the cover plate 10 can be completely fitted with the base plate 20, thereby improving the stability of the auxiliary fixture 100 in installing the lead frame.

[0046] like Figure 5 As shown, in a further embodiment, the auxiliary fixture 100 also includes at least one magnet 30 located at the bottom of the base plate 20, and the magnet 30 is detachably connected to the base plate 20. In this embodiment, the magnet 30 is detachably connected to the base plate 20 so that when disassembling the lead frame, the magnet 30 can be removed from the base plate 20 first, thereby gradually weakening the adsorption performance of the cover plate 10 and the base plate 20, facilitating the separation of the cover plate 10 and the lead frame from the base plate 20, thereby improving the ease of use of the auxiliary fixture 100 for the lead frame.

[0047] In a further embodiment, there are multiple magnets 30, which are evenly spaced and arranged at the bottom of the base plate 20. In this embodiment, by providing multiple magnets 30 evenly spaced at the bottom of the base plate 20, the cover plate 10 and the base plate 20 can be completely attracted and adhered, avoiding uneven distribution of magnets 30 that would result in weak attraction strength at some locations between the cover plate 10 and the base plate 20, thereby preventing the lead frame from slipping off.

[0048] In this embodiment, the cover plate 10 is made of aluminum-iron alloy, and the base plate 20 is also made of aluminum-iron alloy. The base plate 20 contains multiple magnets 30, which are neodymium iron boron (NdFeB) magnets. Specifically, NdFeB magnets have a very high magnetic field strength, providing strong magnetic force. Furthermore, NdFeB magnets have good high-temperature resistance, with a maximum operating temperature exceeding 500°C. This ensures that the mounting or welding mechanism does not affect the magnetic attraction of the base plate 20 when applying adhesive or welding to the lead frame under high-temperature conditions, thereby improving the magnetic stability of the base plate 20 and preventing the cover plate 10 from slipping and affecting the flatness of the lead frame. Additionally, NdFeB magnets are small and lightweight. Placing them inside or at the bottom of the base plate 20 does not significantly increase its weight, thus improving the ease of use of the auxiliary fixture 100 for the lead frame.

[0049] In other embodiments, the cover plate 10 may be made of aluminum-cobalt alloy or aluminum-nickel alloy, the base plate 20 may be made of aluminum-cobalt alloy or aluminum-nickel alloy, and the magnet 30 may be made of samarium-cobalt magnet.

[0050] In this embodiment, the base plate 20, the cover plate 10, and the lead frame are connected by a mechanical structure. The base plate 20 is provided with a plurality of first positioning holes 24, the cover plate 10 is provided with a plurality of second positioning holes 25, each first positioning hole 24 is arranged corresponding to a second positioning hole 25, and the lead frame is provided with a plurality of third positioning holes arranged corresponding to the first positioning holes 24. Positioning elements are inserted through the second positioning holes 25, the third positioning holes, and the first positioning holes 24 to fix the base plate 20, the cover plate 10, and the lead frame by a mechanical structure.

[0051] In this embodiment, the base plate 20 is provided with a first positioning groove, and the cover plate 10 is provided with a positioning protrusion. The positioning protrusion passes through the third positioning hole and cooperates with the first positioning groove to fix and connect the cover plate 10, the lead frame and the base plate 20, thereby limiting the position of the lead frame.

[0052] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0053] The embodiments described above are merely illustrative of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. An auxiliary fixture for a lead frame, used for fixing and mounting the lead frame, the lead frame comprising a plurality of spaced-apart pads, characterized in that, The auxiliary fixture includes: The cover plate includes multiple limiting holes, each of which corresponds to one of the pads, and the cover plate is made of magnetic material. A base plate is located at the bottom of the cover plate, and a limiting groove is provided at the top of the base plate. The limiting groove is used to limit the lead frame. The base plate is configured to be connected to the cover plate by magnetic attraction so that the lead frame is fixedly installed between the cover plate and the base plate. The limiting groove is flush with the top of the lead frame; The auxiliary fixture also includes: At least one magnet is located at the bottom of the base plate, and the magnet is detachably connected to the base plate.

2. The auxiliary fixture according to claim 1, characterized in that, The base plate is also provided with at least one weight-reducing hole, which is located at the bottom of the base plate.

3. The auxiliary fixture according to claim 2, characterized in that, The number of weight-reducing holes is multiple, and the multiple weight-reducing holes are evenly spaced on the bottom of the base plate.

4. The auxiliary fixture according to claim 3, characterized in that, The base plate is also provided with two clearance grooves, which are located at opposite ends of the base plate.

5. The auxiliary fixture according to claim 4, characterized in that, The end of the relief groove near the limiting groove is provided with a weight reduction hole.

6. The auxiliary fixture according to any one of claims 1-5, characterized in that, The number of magnets is multiple, and the multiple magnets are evenly spaced at the bottom of the base plate.

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