ESOP deep bending lead frame

Abstract

The utility model relates to the technical field of semiconductor packaging, and discloses an ESOP deep-bending lead frame, which comprises a frame body and a lead frame group arranged in the frame body, the lead frame group is provided with a lead frame unit, the lead frame unit is provided with a plurality of base islands which form abutments downwards, and the base islands are arranged on the frame body. When the lead frame unit is packaged, the bottom of the abutment can be exposed to improve heat dissipation, the abutment structure with the bottom exposed is formed downwards through the base island, the heat dissipation area is remarkably increased, heat generated by a chip can be dissipated more effectively, the problem that a traditional ESOP lead frame is insufficient in heat dissipation is solved, and the service life of the ESOP lead frame is prolonged. And the working stability and reliability of the chip are improved.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor packaging technology, and in particular to an ESOP deep bending lead frame. Background Technology

[0002] In the semiconductor packaging field, ESOP (Electronic Semiconductor Package) is widely used in various electronic devices due to its small size and good electrical performance. However, as the performance of electronic devices continues to improve, the power consumption of chips is also increasing, making heat dissipation a more prominent issue.

[0003] Traditional ESOP leadframes have shortcomings in thermal design and cannot effectively meet the heat dissipation requirements of chips. For example, existing leadframes may not have a dedicated structure for heat dissipation, or the heat dissipation structure may not be fully effective after packaging, leading to excessively high chip temperatures during operation, which in turn affects the chip's performance and lifespan. Utility Model Content

[0004] This invention addresses the shortcomings of existing technologies by providing an ESOP deep-bend lead frame. Through optimized design of the lead frame structure, it solves the problem of poor heat dissipation in existing technologies, improves the heat dissipation performance of the chip after packaging, and thus enhances the overall performance and reliability of the chip.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] An ESOP deep bend lead frame includes a frame body and a lead frame assembly disposed within the frame body. The lead frame assembly is provided with lead frame units, and each lead frame unit is provided with a plurality of base islands forming downward piers. When the lead frame unit is encapsulated, the bottom of its piers can be exposed to improve heat dissipation.

[0007] Preferably, there are multiple lead frame groups, which are arranged laterally on the frame body and are equidistant from each other.

[0008] Preferably, a longitudinal rib is provided between each two adjacent lead frame assemblies to connect them together, and the longitudinal rib is provided in the frame body.

[0009] Preferably, the lead frame unit has multiple base islands, each of which includes base island one, base island two, and base island three. Base island one and base island two are provided with bending holes, and base island one and base island two are bent downward to form a platform.

[0010] Preferably, both base island one and base island two bend downwards through multiple bending points to form the pier.

[0011] Preferably, the bending angle of the bending point is 40~50°, and the downward bending height of the bending point is 0.39~0.43mm.

[0012] Preferably, the lead frame assembly has multiple lead frame units both horizontally and vertically.

[0013] Preferably, the lead frame unit has multiple pins on both the top and bottom that are connected to the lead frame group.

[0014] Preferably, the lead frame unit has a plurality of solder joints.

[0015] Preferably, the lead frame unit is further provided with several electroplating areas.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] By forming a pier structure with the bottom exposed by the base island downwards, the heat dissipation area is significantly increased, which allows the heat generated by the chip to be dissipated more effectively. This solves the problem of insufficient heat dissipation of traditional ESOP lead frames and improves the working stability and reliability of the chip.

[0018] The optimized design of bending points, longitudinal ribs, and positioning holes ensures the stability of the lead frame during processing, packaging, and use, and reduces performance problems caused by structural deformation. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0021] Figure 2 This is a structural view of the frame body of this utility model;

[0022] Figure 3 This is a structural view of the lead frame unit of this utility model;

[0023] Figure 4 This is a view showing the location of the electroplating area in this utility model.

[0024] Figure 5 This is a bending view of the bending point of this utility model.

[0025] Drawing number explanation: 1. Frame body; 11. Positioning hole; 2. Lead wire frame assembly; 3. Longitudinal rib; 4. Lead wire frame unit; 41. Base island one; 42. Base island two; 43. Base island three; 44. Base island four; 45. Bending hole; 46. Bending point; 47. Pin; 48. Fine point; 49. Electroplating area. Detailed Implementation

[0026] The present invention will now be described in further detail with reference to the accompanying drawings.

[0027] The following description is intended to disclose the present invention so that those skilled in the art can implement it. The preferred embodiments described below are merely examples, and other obvious modifications will be apparent to those skilled in the art. The basic principles of the present invention defined in the following description can be used in other embodiments, modifications, improvements, equivalents, and other technical solutions that do not depart from the spirit and scope of the present invention.

[0028] Those skilled in the art should understand that in the disclosure of this utility model, the terms "longitudinal", "lateral", "up", "down", "left", "right", "front", "rear", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or position based on the orientation or positional relationship shown in the accompanying drawings. They are only for the purpose of simplifying the description of this utility model and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the above terms should not be construed as limitations on this utility model.

[0029] It is understood that the term "a" should be understood as "at least one" or "one or more", that is, in one embodiment, the number of an element can be one, while in another embodiment, the number of the element can be multiple, and the term "a" should not be understood as a limitation on the number. Example

[0030] Please see Figure 1-5 An ESOP deep-bend lead frame includes a lead frame unit 4 and a frame body 1. The frame body 1 has a lead frame assembly 2, and the lead frame unit 4 is disposed on the lead frame assembly 2. The lead frame unit 4 has a base island, which forms a pier downwards through a specific structure. During encapsulation, the bottom of the pier is exposed to achieve heat dissipation. This structural design provides a basis for solving heat dissipation problems; the exposed bottom of the pier can directly contact the heat dissipation device or the external environment, increasing the heat dissipation area and improving heat dissipation efficiency.

[0031] The base island includes base island one 41, base island two 42, and base island three 43. Base island one 41 and base island two 42 are bent downwards through multiple bending points 46 to form a platform. The position and number of bending points 46 have been optimized to ensure the stability of the platform during heat dissipation. At the same time, the angle range of the bending points 46 is between 40° and 50°, with the optimal angle being 48°. The downward bending height ranges from 0.39 to 0.43 mm. This angle and height setting can ensure the heat dissipation effect of the platform while maintaining its structural strength, so that the platform remains stable during the packaging process and chip operation, and will not deform due to external forces or thermal stress, thus affecting the heat dissipation performance.

[0032] The frame body 1 is composed of multiple rows of lead frame groups 2, with multiple positioning holes 11 on both the top and bottom sides. The positioning holes 11 play a key role in the packaging process, which can accurately fix the position of the frame body 1 and ensure the accuracy and consistency of the packaging. Each pair of adjacent lead frame groups 2 are connected by longitudinal ribs 3. The longitudinal ribs 3 enhance the structural rigidity of the entire lead frame and prevent deformation due to external forces during processing and use, thus ensuring the overall stability of the lead frame. In addition, multiple lead frame units 4 are provided on the lead frame group 2 in both the horizontal and vertical directions. This layout design enables the simultaneous packaging of multiple chips, improving production efficiency and space utilization.

[0033] The lead frame unit 4 has multiple pins 47 connected to the lead frame group 2 on both the top and bottom. The pins 47 are important components for realizing the electrical connection between the chip and the external circuit. At the same time, the lead frame unit 4 also includes precision solder joints, which are used to ensure the reliability and stability of the connection between the pins 47 and the external circuit, and to avoid the degradation of electrical performance or circuit failure caused by poor connection.

[0034] The lead frame unit 4 also includes an electroplating area 49, which uses specific electroplating materials and processes. Its main function is to prevent oxidation and corrosion of the lead frame, thereby improving its electrical performance and service life. By performing appropriate electroplating treatment in the electroplating area 49, the lead frame can be effectively protected, ensuring stable operation under various working environments.

[0035] Bending holes 45 are provided on base island 1 41 and base island 2 42. The shape and position of the bending holes 45 match the bending point 46 to ensure the accuracy of the bending process and the integrity of the pier structure. During the bending process, the bending holes 45 can disperse stress and avoid stress concentration that could cause the base island material to crack or deform, thereby ensuring the structural strength and heat dissipation performance of the pier.

[0036] The frame body 1 and lead frame assembly 2 are fabricated using suitable metallic materials (such as copper alloys, which have good electrical and thermal conductivity) through stamping or etching processes. Multiple positioning holes 11 are formed on the upper and lower sides of the frame body 1 according to design requirements. The positional accuracy of the positioning holes 11 must be strictly controlled to ensure accurate installation of the lead frame during the packaging process. Simultaneously, longitudinal ribs 3 are formed between adjacent sets of lead frame assemblies 2. The width and thickness of the longitudinal ribs 3 are determined according to actual needs to ensure sufficient structural strength.

[0037] Multiple leadframe units 4, distributed laterally and longitudinally, are fabricated on the leadframe assembly 2. For the base islands in the leadframe unit 4, bending holes 45 are formed on base island 1 41 and base island 2 42 by means of die stamping, etc. The shape and position of the bending holes 45 need to match the subsequent bending process. The positions of multiple bending points 46 are determined on base island 1 41 and base island 2 42. Through a specific bending process, base island 1 41 and base island 2 42 are bent downward to form a pedestal structure for heat dissipation. Pins 47 connected to the leadframe assembly 2 are fabricated on the upper and lower sides of the leadframe unit 4. The length, width, and spacing of the pins 47 are designed according to the electrical connection requirements of the chip. Precision solder joints are set at the key parts where the pins 47 connect to the external circuit, and a soldering process is used to ensure... The quality of the solder joints ensures the reliability and stability of the connection between pin 47 and the external circuit. Electroplating is performed on the electroplating area 49 on the lead frame unit 4. Appropriate electroplating materials (such as nickel, gold, etc.) are selected, and the thickness and process parameters of the electroplating layer are determined according to actual needs to prevent oxidation and corrosion of the lead frame and improve its electrical performance and service life. During the packaging process, the chip is placed on the base island (such as base island 3 43 and other base island positions that may be used to place the chip). The chip is connected to the pin 47 through bonding and other processes. The lead frame is precisely fixed in the packaging mold using the positioning holes 11 on the frame body 1 for subsequent packaging operations. After packaging, the bottom of the platform is exposed and can contact the heat sink or other heat dissipation devices to achieve effective heat dissipation of the chip.

[0038] Those skilled in the art should understand that the embodiments of the present invention described above and shown in the accompanying drawings are merely examples and do not limit the present invention. The purpose of the present invention has been fully and effectively achieved. The functions and structural principles of the present invention have been shown and explained in the embodiments. Without departing from the stated principles, the implementation of the present invention may have any variations or modifications.

Claims

1. An ESOP deep-bend lead frame comprising a frame body (1) and a lead frame group (2) arranged in the frame body (1), characterized in that: The lead frame group (2) is provided with a lead frame unit (4), the lead frame unit (4) is provided with a plurality of base islands forming piers downward, and the pier bottom of the lead frame unit (4) can be exposed to improve heat dissipation during packaging.

2. An ESOP deep draw leadframe according to claim 1, wherein: The lead frame group (2) is provided with a plurality of lead frame groups (2), and the plurality of lead frame groups (2) are transversely arranged on the frame body (1).

3. An ESOP deep draw leadframe according to claim 2, wherein: Every two adjacent lead frame groups (2) are provided with a longitudinal rib (3) connecting them together, and the longitudinal rib (3) is arranged in the frame body (1).

4. An ESOP deep draw leadframe according to claim 3, wherein: The base islands on the lead frame unit (4) are provided with a plurality of base islands, and the plurality of base islands respectively include a base island one (41), a base island two (42) and a base island three (43), wherein the base island one (41) and the base island two (42) are both provided with a bending hole (45), and the base island one (41) and the base island two (42) are bent downward to form a pier.

5. An ESOP deep draw leadframe according to claim 4, wherein: The base island one (41) and the base island two (42) are both bent downward through a plurality of bending points (46) to form the pier.

6. An ESOP deep draw leadframe according to claim 5, wherein: The bending angle of the bending point (46) is 40-50°, and the downward bending height of the bending point (46) is 0.39-0.43mm.

7. An ESOP deep draw leadframe according to claim 2, wherein: The lead frame group (2) is provided with a plurality of lead frame units (4) transversely and longitudinally.

8. An ESOP deep draw leadframe according to claim 6, wherein: The lead frame unit (4) is provided with a plurality of pins (47) connected with the lead frame group (2) upward and downward.

9. An ESOP deep draw leadframe according to claim 8, wherein: The lead frame unit (4) is provided with a plurality of welding points.

10. An ESOP deep draw leadframe according to claim 9, wherein: The lead frame unit (4) is also provided with a plurality of electroplating areas (49).

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