Pin structure and power module

Abstract

The utility model discloses a kind of PIN structure and power module, it is related to PIN structure technical field, PIN structure includes: connecting portion and welding portion, the welding portion is set in the one end of the connecting portion, the welding portion is provided with at least two protrusions along the circumference of the welding portion, recess is formed between adjacent protrusions.The power module includes the PIN structure.The PIN structure and power module of the utility model improve surface wettability, solve the problem of incomplete tin climbing of tin paste, enhance the welding strength, optimize the heat conduction path, improve the heat dissipation performance.

Description

Technical Field

[0001] This utility model relates to the field of PIN pin structure technology, and in particular to a PIN pin structure and power module. Background Technology

[0002] In power module packaging technology, the PIN pin structure, as a key component connecting internal chips to external circuits, directly affects the module's electrical performance, thermal management capabilities, and long-term reliability through its soldering quality. Traditional PIN pin structures typically employ a cylindrical or flat, straight-leg design, with surfaces treated with nickel or gold plating to improve conductivity and corrosion resistance. However, in practical applications, especially in high-power, high-temperature, and high-vibration environments, traditional PIN pin structures exhibit the following technical problems during soldering:

[0003] While existing surface treatments for PIN structures (such as nickel plating and gold plating) improve conductivity and corrosion resistance, insufficient surface wettability of the PIN structure leads to incomplete solder paste wetting during reflow soldering. This results in uneven and incomplete solder paste wetting, making it difficult for the paste to evenly and completely reach the contact area between the PIN structure and the substrate. This causes defects such as voids, cold solder joints, or incomplete solder joints at the solder interface. When solder paste wetting is incomplete, the effective contact area at the solder interface decreases, leading to insufficient solder strength. Traditional PIN structures typically employ cylindrical or flat straight-leg designs, which also struggle to create sufficient solder joint contact area during soldering. Due to the small effective contact area at the solder interface, solder strength is significantly reduced. Under high vibration or mechanical stress environments, solder joints are prone to cracking or detachment, causing a decrease in the reliability of the power module. Insufficient solder interface not only reduces solder strength but also significantly increases thermal resistance, affecting the heat conduction efficiency of the power module. Especially in high-temperature environments, this can lead to localized overheating, which may cause module performance degradation or failure, affecting the module's lifespan.

[0004] The aforementioned issues severely affect the welding strength and electrical connection reliability between the PIN structure and the substrate, potentially leading to electrical connection failures and consequently reducing the overall performance and long-term stability of the power module. Utility Model Content

[0005] The purpose of this invention is to provide a PIN pin structure and power module to solve the problems existing in the prior art, improve surface wettability, solve the problem of incomplete solder paste climbing, enhance soldering strength, optimize heat conduction path, and improve heat dissipation performance.

[0006] To achieve the above objectives, this utility model provides the following solution:

[0007] This utility model provides a PIN pin structure, including: a connecting part and a soldering part, wherein the soldering part is disposed at one end of the connecting part, and the soldering part has at least two protrusions arranged circumferentially along the soldering part, and a groove is formed between adjacent protrusions.

[0008] In some embodiments, the outer surfaces of each of the protrusions are located on the same circumferential surface.

[0009] In some embodiments, the bottom of each of the grooves is located on the same circumferential surface.

[0010] In some embodiments, all the protrusions are the same size.

[0011] In some embodiments, all the grooves are the same size.

[0012] In some embodiments, the depth of the groove is between 0 mm and 0.35 mm.

[0013] In some embodiments, a first inclined surface and a second inclined surface are provided on one side of the protrusion, the first inclined surface and the second inclined surface are connected, and a third inclined surface and a fourth inclined surface are provided on the other side of the protrusion, the third inclined surface and the fourth inclined surface are connected.

[0014] In some embodiments, the first inclined plane is symmetrically arranged with the second inclined plane, and the third inclined plane is symmetrically arranged with the fourth inclined plane; the first inclined plane is symmetrically arranged with the third inclined plane, and the second inclined plane is symmetrically arranged with the fourth inclined plane.

[0015] In some embodiments, the plane perpendicular to the axial direction of the PIN structure is a reference plane, and the inclination angles between the first inclined plane and the reference plane, the second inclined plane and the reference plane, the third inclined plane and the reference plane, and the fourth inclined plane and the reference plane are all between 0° and 45°.

[0016] This utility model also provides a power module, including the aforementioned PIN pin structure.

[0017] The present invention achieves the following technical advantages over the prior art:

[0018] This embodiment utilizes a groove formed between two adjacent protrusions, allowing solder paste to move along the groove towards the connection point and also towards the protrusion. This ensures the solder paste adheres to both the groove and the protrusion, improving its wettability and guaranteeing that it evenly and completely climbs to the contact area between the PIN and the substrate during soldering, thereby eliminating defects such as voids and cold solder joints. Furthermore, the protrusions and grooves expand the effective contact area of ​​the solder interface, significantly improving solder strength and ensuring the stability and reliability of the solder joint under high vibration or mechanical stress environments. Additionally, it reduces the thermal resistance of the solder interface, improves the heat conduction efficiency of the power module, avoids localized overheating, and extends the lifespan of the power module. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, 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 an isometric view of the PIN pin structure in some embodiments of the present invention;

[0021] Figure 2 This is a bottom view of the welded part in some embodiments of this utility model;

[0022] Figure 3 This is a schematic diagram of the first and second circumferential surfaces in some embodiments of the present invention;

[0023] Figure 4 This is a front view of the welding part in some embodiments of this utility model;

[0024] Figure 5 This is a schematic diagram of the reference plane in some embodiments of the present invention;

[0025] Figure 6 This is a schematic diagram showing the front view sectioning position of the welded part in some embodiments of this utility model;

[0026] Figure 7 for Figure 6 AA section view;

[0027] In the diagram: 100-PIN pin structure, 1-connector, 2-soldering part, 3-protrusion, 4-groove, 5-first bevel, 6-second bevel, 7-third bevel, 8-fourth bevel, 9-bending part, 10-first circumferential surface, 11-second circumferential surface, 12-reference surface. Detailed Implementation

[0028] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0029] The purpose of this invention is to provide a PIN pin structure and power module to solve the problems existing in the prior art, improve surface wettability, solve the problem of incomplete solder paste climbing, enhance soldering strength, optimize heat conduction path, and improve heat dissipation performance.

[0030] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0031] Example 1

[0032] like Figures 1 to 7 As shown, this embodiment provides a PIN pin structure 100, including: a connecting part 1 and a soldering part 2, which are integrally formed. The soldering part 2 is disposed at one end of the connecting part 1. The connecting part 1 is needle-shaped. A bending part 9 for stress buffering is provided near the soldering part 2 on the connecting part 1. The bending part 9 is bent plate-shaped. At least two protrusions 3 are provided along the circumference of the soldering part 2, and a groove 4 is formed between adjacent protrusions 3. In this embodiment, the groove 4 formed between two adjacent protrusions 3 allows solder paste to move along the groove 4 towards the connecting part 1, and the solder paste can move along the groove 4 towards the protrusion 3, so that the solder paste adheres to the area of ​​the groove 4 and the protrusion 3, improving the wettability of the solder paste and ensuring that the solder paste can uniformly and completely climb to the contact area between the PIN pin and the substrate during the soldering process, thereby eliminating defects such as solder voids and cold solder joints. Furthermore, by providing the protrusions 3 and the groove 4, the effective contact area of ​​the soldering interface is expanded, significantly improving the soldering strength and ensuring the stability and reliability of the solder joint under high vibration or mechanical stress environments. Furthermore, it reduces the thermal resistance of the welding interface, improves the heat conduction efficiency of the power module, avoids local overheating problems, and extends the service life of the power module.

[0033] Specifically, in some embodiments, the outer surface of each protrusion 3 is an arc surface, and the outer surface of each protrusion 3 is located on the same circumferential surface or not on the same circumferential surface, preferably on the same circumferential surface, and the circumferential surface where the outer surface of each protrusion 3 is located is the first circumferential surface 10.

[0034] In some embodiments, the bottom of each groove 4 is an arc surface, and the bottom of each groove 4 is located on the same circumferential surface or not on the same circumferential surface, preferably on the same circumferential surface. The circumferential surface where the bottom of each groove 4 is located is the second circumferential surface 11, and the second circumferential surface 11 is concentrically arranged with the first circumferential surface 10.

[0035] In some embodiments, the protrusions 3 are uniformly arranged along the circumference of the welding part 2, and the size of each protrusion 3 may be the same or different, preferably the same; the size of each groove 4 may be the same or different, preferably the same. Setting the size of each protrusion 3 and the size of each groove 4 to be the same facilitates the processing of the welding part 2.

[0036] In some embodiments, the depth of the groove 4 refers to the distance between the circumferential surface of the outer side of the protrusion 3 and the circumferential surface of the bottom of the groove 4, that is, the distance between the first circumferential surface 10 and the second circumferential surface 11. The depth t of the groove 4 is between 0 mm and 0.35 mm, which can enhance the wettability of the solder paste.

[0037] In some embodiments, the shapes of the protrusion 3 and the groove 4 can be set as needed. For example, one side of the protrusion 3 is provided with a first inclined surface 5 and a second inclined surface 6, the first inclined surface 5 and the second inclined surface 6 are connected, and the first inclined surface 5 and the second inclined surface 6 are smoothly transitioned at the connection point. The other side of the protrusion 3 is provided with a third inclined surface 7 and a fourth inclined surface 8, the third inclined surface 7 and the fourth inclined surface 8 are connected, and the third inclined surface 7 and the fourth inclined surface 8 are smoothly transitioned at the connection point.

[0038] In some embodiments, the first inclined plane 5 and the second inclined plane 6 are symmetrically arranged, and the third inclined plane 7 and the fourth inclined plane 8 are symmetrically arranged; the first inclined plane 5 and the third inclined plane 7 are symmetrically arranged, and the second inclined plane 6 and the fourth inclined plane 8 are symmetrically arranged. The areas of the first inclined plane 5, the second inclined plane 6, the third inclined plane 7 and the fourth inclined plane 8 are preferably equal.

[0039] In some embodiments, the first inclined plane 5 is from top to bottom (with) Figure 4 (Based on the main viewpoint) from the protrusion 3 where the first inclined plane 5 is located, in a counterclockwise direction (with...) Figure 2 (Based on the upward viewing angle) Adjacent protrusions 3 are inclined, and the second inclined surface 6 is arranged from bottom to top (with... Figure 4 (Based on the main viewpoint) from the protrusion 3 where the second inclined plane 6 is located, in a counterclockwise direction (with...) Figure 2 (Based on the upward viewing angle) The adjacent protrusions 3 are set at an angle, and the third inclined surface 7 is arranged from top to bottom (with... Figure 4 (Based on the main viewpoint) from the protrusion 3 where the third inclined plane 7 is located, in a clockwise direction (with...) Figure 2 (Based on the upward viewing angle) The adjacent protrusions 3 are set at an angle, and the fourth inclined surface 8 is arranged from bottom to top (with... Figure 4 From the main viewpoint, from the protrusion 3 where the fourth inclined plane 8 is located, in a clockwise direction (with... Figure 2 (Based on the upward viewing angle) The adjacent protrusions 3 are set at an angle.

[0040] In some embodiments, the plane perpendicular to the axial direction of the PIN structure 100 (the axial direction of the PIN structure 100 refers to the axial direction of the connecting part 1) is the reference plane 12. The inclination angles between the first inclined surface 5 and the reference plane 12, the second inclined surface 6 and the reference plane 12, the third inclined surface 7 and the reference plane 12, and the fourth inclined surface 8 and the reference plane 12 are all θ, which is between 0° and 45°. By changing the size of the inclination angle θ, the shape of the groove 4 and the protrusion 3 can be adjusted.

[0041] In some embodiments, the radius of the circle containing the first circumferential surface 10 is R, the number of grooves 4 and protrusions 3 is n, the arc length of the projection of the widest position of protrusion 3 onto the first circumferential surface 10 is b, the arc length of the projection of the narrowest position of groove 4 onto the first circumferential surface 10 is e, the height of groove 4 and protrusion 3 is 2a, the length of the first inclined surface 5, the second inclined surface 6, the third inclined surface 7 or the fourth inclined surface 8 is h, and sinθ=a / h. When the condition (b+e)n=2πR is satisfied, the size of the protrusions 3 and grooves 4 of the welding part 2 is changed by changing the size of the tilt angle θ.

[0042] The PIN pin structure 100 of this embodiment improves the specific structure of the soldering portion 2 by using alternating protrusions 3 and grooves 4 to enhance the wettability and flowability of the solder paste. This ensures that the solder paste can uniformly and completely cover the contact area between the PIN pin structure 100 and the substrate during the soldering process, thereby eliminating defects such as solder voids and cold solder joints. By setting the protrusions 3 and grooves 4, the effective contact area of ​​the soldering interface is expanded, resulting in a significant improvement in soldering strength and effectively preventing soldering defects. In addition, the PIN pin structure 100 of this embodiment can also improve thermal conductivity and mechanical properties, further enhancing the reliability and service life of the power module.

[0043] Example 2

[0044] This embodiment provides a power module, including the PIN pin structure 100 of Embodiment 1. By setting the PIN pin structure 100 of Embodiment 1, this embodiment not only solves the soldering defect problem in the prior art, but also significantly improves the electrical performance, heat dissipation capacity, and long-term reliability of the power module, providing strong support for the development of high-performance power modules.

[0045] This utility model uses specific examples to illustrate its principles and implementation methods. The above description of the embodiments is only for the purpose of helping to understand the method and core idea of ​​this utility model. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the idea of ​​this utility model. In summary, the content of this specification should not be construed as a limitation of this utility model.

Claims

1. A PIN pin structure, characterized in that: include: The connection part and the welding part are provided at one end of the connection part. The welding part has at least two protrusions along the circumference of the welding part, and a groove is formed between adjacent protrusions.

2. The PIN pin structure according to claim 1, characterized in that: The outer surfaces of each of the protrusions are located on the same circumferential surface.

3. The PIN pin structure according to claim 1, characterized in that: The bottom of each groove is located on the same circumferential surface.

4. The PIN pin structure according to claim 1, characterized in that: All the protrusions are the same size.

5. The PIN pin structure according to claim 1, characterized in that: All the grooves described are the same size.

6. The PIN pin structure according to claim 1, characterized in that: The depth of the groove is between 0 mm and 0.35 mm.

7. The PIN pin structure according to claim 1, characterized in that: One side of the protrusion is provided with a first inclined surface and a second inclined surface, which are connected. The other side of the protrusion is provided with a third inclined surface and a fourth inclined surface, which are connected.

8. The PIN pin structure according to claim 7, characterized in that: The first inclined plane is symmetrically arranged with respect to the second inclined plane, and the third inclined plane is symmetrically arranged with respect to the fourth inclined plane; the first inclined plane is symmetrically arranged with respect to the third inclined plane, and the second inclined plane is symmetrically arranged with respect to the fourth inclined plane.

9. The PIN pin structure according to claim 7, characterized in that: The plane perpendicular to the axial direction of the PIN structure is the reference plane. The inclination angles between the first inclined plane and the reference plane, the second inclined plane and the reference plane, the third inclined plane and the reference plane, and the fourth inclined plane and the reference plane are all between 0° and 45°.

10. A power module, characterized in that: Includes the PIN pin structure as described in any one of claims 1-9.

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