Lead frame

Abstract

The utility model discloses a lead frame, which comprises a frame main body, the frame main body is provided with a first end face and a second end face which are opposite to each other, the first end face is recessed towards the direction of the second end face to form a glue locking groove, and the glue locking groove is at least provided with a first cross section and a second cross section. The first cross section is located on the side, away from the first end face, of the second cross section, and the area of the first cross section is larger than that of the second cross section. According to the utility model, the area of the first cross section is larger than that of the second cross section, so that glue at the first cross section cannot be separated from the glue locking groove through the second cross section, thereby increasing the bonding strength between the lead frame and other shelves, effectively reducing the layering probability of packaged products, and prolonging the service life of the packaged products.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductor packaging, in particular to a lead frame. Background Art

[0002] Semiconductor packaging refers to the process of attaching the cut wafer to the corresponding substrate (lead frame) island with glue, and then using ultra-fine metal (gold, tin, copper, aluminum) wires or conductive resins to connect the wafer's bonding pads to the corresponding pins of the substrate to form the required circuit. Among them, the failure phenomenon that often occurs in packaged products is delamination, that is, the lead frame is easily separated from the glue and other plastic packaging materials.

[0003] Based on this, the existing solution is to etch a glue locking groove on the lead frame, thereby increasing the contact area between the lead frame and the plastic packaging material to reduce the probability of delamination.

[0004] However, the existing glue locking grooves are processed by etching, and the glue locking grooves obtained by etching are equal-width grooves, that is, the width of the glue locking grooves at any height is equal, and the two side walls of the glue locking grooves are perpendicular to the bottom surface. This results in the glue locking grooves only increasing the bonding strength by increasing the contact area between the plastic packaging material and the lead frame, and the effect is not good. In some more stringent usage environments, the packaged products still have stratification phenomenon. Summary of the invention

[0005] In view of the above-mentioned deficiencies in the prior art, the technical problem to be solved by the present invention is to provide a lead frame for solving the problem that the lead frame in the packaged product in the prior art is easy to delaminate.

[0006] The technical solution adopted by the utility model to solve the technical problem is a lead frame, comprising:

[0007] A frame body, wherein the frame body has a first end face and a second end face which are opposite to each other, the first end face is recessed toward the second end face to form a glue locking groove, the glue locking groove has at least a first cross section and a second cross section, the first cross section is located on a side of the second cross section away from the first end face, and the area of ​​the first cross section is greater than the area of ​​the second cross section.

[0008] Furthermore, the width of the glue locking groove gradually increases from the first end surface toward the second end surface.

[0009] Furthermore, the glue locking groove has a first side wall and a second side wall on opposite sides, the first side wall gradually inclines toward the second side wall from the second end face toward the first end face; the second side wall gradually inclines toward the first side wall from the second end face toward the first end face.

[0010] Furthermore, the first side wall and the second side wall are symmetrically arranged.

[0011] Furthermore, the glue locking groove has a first connecting section and a second connecting section in sequence along its height direction, the first connecting section is located at an end of the second connecting section close to the second end face, and the cross-sectional area of ​​the first connecting section is larger than the cross-sectional area of ​​the first connecting section.

[0012] Furthermore, a step surface is formed at the connection between the first connecting section and the second connecting section.

[0013] Furthermore, the glue locking groove is provided with at least one entry and exit hole capable of allowing a cutting tool to be inserted therein, and the top surface area of ​​the entry and exit hole is greater than or equal to the bottom surface area of ​​the entry and exit hole.

[0014] Furthermore, the entry and exit holes are cylindrical holes.

[0015] Furthermore, the glue locking groove has a first end and a second end which are opposite to each other, and an entry and exit hole is respectively provided at the first end and the second end.

[0016] Furthermore, the glue locking groove is arranged in a ring shape, and an entry and exit knife hole is provided on the glue locking groove.

[0017] Compared with the prior art, the utility model has at least the following beneficial effects:

[0018] The area of ​​the first cross section is greater than that of the second cross section, so that when plastic packaging materials such as glue enter the glue locking groove and harden, the cross-sectional area of ​​the glue corresponding to the first cross section is greater than the cross-sectional area of ​​the glue at the second cross section, thereby preventing the glue at the first cross section from escaping from the glue locking groove through the second cross section, thereby increasing the bonding strength between the lead frame and other layer frames, effectively reducing the probability of delamination of the packaged product and extending its service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a cross-sectional view of a lead frame and a plastic encapsulation material in an embodiment;

[0020] Figure 2 is a cross-sectional view of a lead frame in an embodiment;

[0021] Figure 3 It is a top view of the lead frame when the glue locking groove is ring-shaped in the embodiment;

[0022] Figure 4 It is a top view of the lead frame when an entry and exit hole is respectively provided at both ends of the glue locking groove in the embodiment;

[0023] Figure 5 It is a top view of the lead frame when a knife entry and exit hole is provided at one end of the glue locking groove in the embodiment;

[0024] Figure 6 It is a top view of the lead frame when a knife entry and exit hole is provided at the middle end of the glue locking groove in the embodiment;

[0025] In the figure:

[0026] 100, frame body; 101, first end surface; 102, second end surface; 110, glue locking groove; 111, inlet and outlet holes; 120, first side wall; 130, second side wall;

[0027] 200. Plastic packaging material. DETAILED DESCRIPTION

[0028] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

[0029] Please refer to Figure 1-Figure 6 The utility model discloses a lead frame, comprising:

[0030] The frame body 100 has a first end face 101 and a second end face 102 which are opposite to each other, the first end face 101 is recessed toward the second end face 102 to form a glue locking groove 110, the glue locking groove 110 has at least a first cross section and a second cross section, the first cross section is located on the side of the second cross section away from the first end face 101, and the area of ​​the first cross section is greater than the area of ​​the second cross section.

[0031] Specifically, the glue locking groove 110 in the present application is different from the existing equal-width groove. It has a first cross-section close to the second end face 102 and a second cross-section close to the first end face 101, and the area of ​​the first cross-section is greater than the area of ​​the second cross-section. When the plastic packaging material 200 such as glue enters the glue locking groove 110 and hardens, the cross-sectional area of ​​the glue corresponding to the first cross-section is greater than the cross-sectional area of ​​the glue at the second cross-section, thereby preventing the glue at the first cross-section from escaping from the glue locking groove 110 through the second cross-section, thereby increasing the bonding strength between the lead frame and other layer frames, effectively reducing the probability of stratification of the packaged product, and extending its service life.

[0032] The first cross section and the second cross section are both cross sections of the glue locking groove 110 . Compared with the second cross section, the first cross section is located deeper in the glue locking groove 110 .

[0033] Furthermore, the width of the glue locking groove 110 gradually increases from the first end surface 101 toward the second end surface 102 .

[0034] The glue locking groove 110 has a first side wall 120 and a second side wall 130 on opposite sides, the first side wall 120 gradually tilts toward the second side wall 130 from the second end face 102 toward the first end face 101; the second side wall 130 gradually tilts toward the first side wall 120 from the second end face 102 toward the first end face 101.

[0035] Specifically, the first side wall 120 and the second side wall 130 are inclined inward from bottom to top, and the first side wall 120 and the second side wall 130 can be configured as a flat surface or a curved surface.

[0036] Furthermore, the first side wall 120 and the second side wall 130 are symmetrically arranged.

[0037] The first side wall 120 and the second side wall 130 are symmetrically arranged, that is, the first side wall 120 and the second side wall 130 have the same inclination angle or bending angle, so that the force on the left and right sides of the molding compound 200 is more uniform.

[0038] Furthermore, the glue locking groove 110 has a first connecting section and a second connecting section in sequence along its height direction, the first connecting section is located at one end of the second connecting section close to the second end surface 102, and the cross-sectional area of ​​the first connecting section is larger than the cross-sectional area of ​​the first connecting section.

[0039] Specifically, the first connecting section is located in a direction close to the bottom surface, and the second connecting section is located in a direction close to the top surface. The cross-section of the first connecting section is larger than the cross-sectional area of ​​the second connecting section, so that after the plastic encapsulation material 200 hardens in the glue locking groove 110, the cross-sectional area of ​​the bottom is larger than the cross-sectional area at the opening, and the hardened plastic encapsulation material 200 is not easy to escape from the glue locking groove 110.

[0040] Furthermore, a step surface is formed at the connection between the first connecting section and the second connecting section.

[0041] Specifically, a step surface is provided between the first connecting section and the second connecting section, so that the hardened plastic encapsulation material 200 also has a step surface that fits with the step surface of the locking groove 110 to increase the bonding strength.

[0042] Furthermore, the glue locking groove 110 is provided with at least one entry and exit hole 111 capable of allowing a tool to be inserted therein, and the top surface area of ​​the entry and exit hole 111 is greater than or equal to the bottom surface area of ​​the entry and exit hole 111 .

[0043] Specifically, the glue locking groove 110 in the present application is formed by cutting with a tool having a larger lower end and a smaller upper end, wherein the tool can be inserted from the entry and exit hole 111, and then cut along a predetermined path to form the glue locking groove 110, and finally exit from the entry and exit hole 111.

[0044] Furthermore, the entry and exit holes 111 are cylindrical holes.

[0045] Furthermore, the glue locking groove 110 has a first end and a second end which are opposite to each other, and a knife entry and exit hole 111 is respectively provided at the first end and the second end.

[0046] Specifically, one or more glue locking grooves 110 are arranged on the frame body 100, and an entry and exit hole 111 is arranged at both ends of each glue locking groove 110. The tool can be inserted into the entry and exit hole 111 at one end, and withdrawn from the entry and exit hole 111 at the other end after cutting is completed.

[0047] Of course, one entry and exit hole 111 may be provided at only one end or the middle of the glue locking groove 110 , and the cutter may extend from the entry and exit hole 111 , and return to the entry and exit hole 111 and exit after cutting is completed.

[0048] Furthermore, the glue locking groove 110 is arranged in a ring shape, and a knife entry and exit hole 111 is provided on the glue locking groove 110 .

[0049] Specifically, the glue locking groove 110 is a closed annular structure, and the tool can extend from the entry and exit hole 111 and cut along a circular path until it returns to the entry and exit hole 111 and exits from the entry and exit hole 111.

[0050] It should be noted that all directional indications (such as up, down, left, right, front, back...) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0051] In addition, in the present invention, the descriptions of "first", "second", "one", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0052] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0053] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

Claims

1. A lead frame, characterized in that: include: A frame body, the frame body having a first end face and a second end face which are opposite to each other, the first end face being recessed toward the second end face to form a glue locking groove, the glue locking groove having at least a first cross section and a second cross section, the first cross section being located on a side of the second cross section away from the first end face, and an area of ​​the first cross section being greater than an area of ​​the second cross section; The glue locking groove is provided with at least one entry and exit hole capable of allowing a tool to be inserted therein, and the top surface area of ​​the entry and exit hole is greater than or equal to the bottom surface area of ​​the entry and exit hole.

2. A lead frame according to claim 1, characterized in that: The width of the glue locking groove gradually increases from the first end surface toward the second end surface.

3. A lead frame according to claim 2, characterized in that: The glue locking groove has a first side wall and a second side wall on opposite sides, the first side wall gradually tilts toward the second side wall from the second end face toward the first end face; the second side wall gradually tilts toward the first side wall from the second end face toward the first end face.

4. A lead frame according to claim 3, characterized in that: The first side wall and the second side wall are symmetrically arranged.

5. The lead frame according to claim 1, characterized in that: The glue locking groove has a first connecting section and a second connecting section in sequence along its height direction, the first connecting section is located at an end of the second connecting section close to the second end surface, and the cross-sectional area of ​​the first connecting section is larger than the cross-sectional area of ​​the first connecting section.

6. The lead frame according to claim 5, characterized in that: A step surface is formed at the connection between the first connecting section and the second connecting section.

7. The lead frame according to claim 1, characterized in that: The inlet and outlet holes are cylindrical holes.

8. The lead frame according to claim 1, characterized in that: The glue locking groove has a first end and a second end which are opposite to each other, and a knife entry and exit hole is respectively provided at the first end and the second end.

9. The lead frame according to claim 1, characterized in that: The glue locking groove is arranged in an annular shape, and a knife entry and exit hole is arranged on the glue locking groove.

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