Lead frame, lead frame array and packaging body

Abstract

The utility model provides a lead frame, a lead frame array and a packaging body, and belongs to the field of semiconductor packaging. The first side edge and the second side edge of the base island are respectively provided with the first groove, the third side edge of the base island is provided with the second groove, and the first groove and the second groove are both arranged on the front surface of the base island and are used for filling plastic packaging materials. During plastic packaging, a plastic packaging material in a hot melting state can flow into the first groove and the second groove, and after the plastic packaging material is solidified, the plastic packaging material in the first groove and the second groove is clamped in the first groove and the second groove. Therefore, after plastic packaging, the connection between the whole plastic packaging layer and the lead frame is firmer, and the plastic packaging layer is not easy to fall off in the subsequent transportation or use process; therefore, the internal structure of the chip can be better protected, and the service life of the chip is prolonged.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor packaging, and more specifically, to a lead frame, a lead frame array, and a package. Background Technology

[0002] Manufacturing a complete chip product typically involves processes such as chip design, wafer fabrication, chip packaging, and testing.

[0003] Chip packaging typically involves bonding a wafer to a base island in the center of a leadframe, and then connecting the wafer to pins via connecting wires to achieve electrical and mechanical connections between the chip's internal components and the external environment. Finally, a molding compound is used to encapsulate the leadframe and wafer. After packaging, the chip has an external molding compound that protects the wafer and its pins.

[0004] As the pursuit of smaller and thinner chip products increases, the thickness of the molding layer becomes smaller with the chip thickness. This can lead to the molding material detaching, resulting in low packaging reliability and stability, and affecting product yield and lifespan. Utility Model Content

[0005] This application provides a lead frame that can effectively solve the above-mentioned or other potential technical problems.

[0006] The first aspect of this application is to provide a lead frame, including a frame body, a base island, and pins; the base island is disposed on the frame body; the base island has a first side, a second side, a third side, and a fourth side; wherein the first side and the second side are disposed opposite to each other, and the third side and the fourth side are disposed opposite to each other; the first side and the second side are respectively provided with a first groove, the third side is provided with a second groove, and the pins are disposed close to the fourth side; the first groove and the second groove are both disposed on the front side of the base island for filling with encapsulating material.

[0007] The lead frame provided in the first aspect of this application has a first groove on the first and second sides of the base island, and a second groove on the third side. Both the first and second grooves are located on the front side of the base island and are used to fill the molding compound. During molding, the hot-melt molding compound flows into the first and second grooves. After the molding compound solidifies, it is trapped within the first and second grooves. Therefore, after molding, the connection between the entire molding layer and the lead frame is more secure, making it less prone to detachment during subsequent transportation or use; this better protects the internal structure of the chip and extends its lifespan.

[0008] In an alternative embodiment according to the first aspect, the first side of the base island has at least two spaced-apart first grooves; the second side of the base island has at least two spaced-apart first grooves.

[0009] In an optional embodiment according to the first aspect, the first groove on the first side and the first groove on the second side are disposed opposite to each other.

[0010] In an optional embodiment according to the first aspect, the first side and the second side of the base island are respectively provided with protrusions extending to both sides, the protrusions and the sidewalls of the base island forming the first groove.

[0011] In an optional embodiment according to the first aspect, the boss has a groove surface and a connecting surface; the groove surface is a horizontal surface, and the groove surface and the first sidewall of the base island form an L-shaped first groove; the connecting surface extends toward a side away from the first groove and connects to the second sidewall of the base island; the connecting surface is convex arc-shaped; the second sidewall on the same side protrudes outward relative to the first sidewall.

[0012] In an alternative embodiment according to the first aspect, the second groove extends through a strip-shaped channel on the third side of the base island.

[0013] In an alternative embodiment according to the first aspect, the second groove includes a first stepped groove and a second stepped groove, the second stepped groove being located at the bottom of the first stepped groove and communicating with the first stepped groove, the overall width of the second stepped groove being smaller than that of the first stepped groove.

[0014] In an alternative embodiment according to the first aspect, the second groove has a trapezoidal cross-section, and the width of the second groove gradually decreases along the direction close to the first groove.

[0015] A second aspect of this application also provides a lead frame array comprising a plurality of the aforementioned lead frames; the plurality of lead frames are connected as a single unit.

[0016] The lead frame array provided in the second aspect of this application, because it includes the aforementioned lead frame, also has the aforementioned effect of a more secure connection between the entire molding layer and the lead frame, making it less likely to fall off during subsequent transportation or use; thereby enabling better protection of the internal structure of the chip and improving its service life.

[0017] A third aspect of this application also provides a package comprising the lead frame, wafer, and molding compound described above; wherein the wafer is disposed on the front side of the base island, the first and second grooves on the front side of the base island are filled with the molding compound, and the back side of the base island and a portion of the pins are exposed outside the molding compound.

[0018] The package provided in the third aspect of this application, because it includes the aforementioned lead frame, also has the aforementioned effect of a more secure connection between the entire molding layer and the lead frame, making it less likely to fall off during subsequent transportation or use; thereby enabling better protection of the internal structure of the chip and improving its service life.

[0019] The beneficial effects of this utility model are:

[0020] This invention, through the aforementioned design, provides a lead frame, lead frame array, and package. The first and second sides of the base island are respectively provided with a first groove, and the third side is provided with a second groove. Both the first and second grooves are located on the front side of the base island and are used to fill the molding compound. During molding, the hot-melt molding compound flows into the first and second grooves. After the molding compound solidifies, it is trapped within the first and second grooves. Therefore, after molding, the connection between the entire molding layer and the lead frame is more secure, making it less prone to detachment during subsequent transportation or use; thus, the internal structure of the chip is better protected, extending its service life. Attached Figure Description

[0021] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the lead frame provided in an embodiment of the present invention (where the cross-sectional lines represent grooves).

[0023] Figure 2 This is provided by the embodiment of the present utility model. Figure 1 Middle AA sectional view (where the section lines represent the leader frame entity);

[0024] Figure 3 This is provided by the embodiment of the present utility model. Figure 1 Cross-sectional view of the first and second grooves (where the section lines represent the lead frame entity);

[0025] Figure 4 This is provided by the embodiment of the present utility model. Figure 3 A partial enlarged view of the second groove in the image (where the cross-section represents the lead frame entity).

[0026] Figure 5 This is a schematic diagram of the frame array provided in an embodiment of the present invention.

[0027] Explanation of reference numerals in the attached figures:

[0028] 10. Lead frame; 13. Base island; 131. First side; 132. Second side; 133. Third side; 134. Fourth side; 135. First groove; 136. Second groove; 1361. First stepped groove; 1362. Second stepped groove; 137. Boss; 1371. Groove surface; 1372. Connecting surface; 15. Pin; 20. Frame array. Detailed Implementation

[0029] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0030] like Figure 1 and Figure 3 This embodiment provides a novel lead frame 10, including a frame body, a base island 13, and pins 15. The base island 13 is disposed on the frame body. The base island 13 has a first side 131, a second side 132, a third side 133, and a fourth side 134. The first side 131 and the second side 132 are disposed opposite to each other, and the third side 133 and the fourth side 134 are disposed opposite to each other. The first side 131 and the second side 132 are respectively provided with a first groove 135, and the third side 133 is provided with a second groove 136. The pins 15 are disposed near the fourth side 134. The first groove 135 and the second groove 136 are both disposed on the front side of the base island 13 for filling with encapsulating material.

[0031] The base island 13 is located on the frame body (e.g., in the middle of the frame body). The base island 13 is used to mount the wafer, and the wafer is electrically connected to multiple pins 15 via multiple wires. After the connection is completed, the wires (not shown in the figure), pins 15 and wafer are encapsulated.

[0032] The lead frame 10, lead frame array 20, and package provided by this utility model feature a first groove 135 on the first side 131 and the second side 132 of the base island 13, and a second groove 136 on the third side 133. Both the first groove 135 and the second groove 136 are located on the front side of the base island 13 and are used to fill the encapsulation material. During encapsulation, the hot-melt encapsulation material flows into the first groove 135 and the second groove 136. After the encapsulation material solidifies, it is trapped within the first groove 135 and the second groove 136. Therefore, after encapsulation, the connection between the entire encapsulation layer and the lead frame 10 is more secure, making it less likely to detach during subsequent transportation or use. This, in turn, provides better protection for the internal structure of the chip and extends its service life.

[0033] Please continue to refer to this. Figure 1 The base island 13 is generally rectangular, and the first side 131 of the base island 13 has at least two spaced-apart first grooves 135; the second side 132 of the base island 13 has at least two spaced-apart first grooves 135.

[0034] Furthermore, in this embodiment, the first side 131 of the base island 13 is provided with two spaced-apart first grooves 135; the second side 132 of the base island 13 has two spaced-apart first grooves 135.

[0035] It is understood that the specific number of the first grooves 135 is not limited here. In other specific embodiments, the number of the first grooves 135 on the first side 131 and the second side 132 of the base island 13 can be set to three or more, depending on the user's needs. This multi-point connection can effectively enhance the stability of the connection.

[0036] Specifically, in this embodiment, the first groove 135 on the first side 131 and the first groove 135 on the second side 132 are arranged opposite to each other. This arrangement makes the overall structure of the base island 13 symmetrical, effectively avoiding stress concentration problems and thus achieving structural stability.

[0037] like Figure 2 Furthermore, the first side 131 and the second side 132 of the base island 13 are respectively provided with protrusions 137 extending to both sides, and the protrusions 137 and the sidewalls of the base island 13 form the first groove 135. This arrangement makes the processing of the first groove 135 simpler and more convenient.

[0038] In an optional exemplary embodiment, the boss 137 has a groove surface 1371 and a connecting surface 1372; the groove surface 1371 is a horizontal surface, and the groove surface 1371 and the first sidewall of the base island 13 form an L-shaped first groove 135. This arrangement makes the first groove 135 simpler and more convenient to construct. The connecting surface 1372 extends toward the side away from the first groove 135 and connects to the second sidewall of the base island 13; the second sidewall on the same side protrudes outward relative to the first sidewall; the connecting surface 1372 is convex arc-shaped, and the arc transition effectively avoids stress concentration problems caused by sharp structural corners.

[0039] In an alternative exemplary embodiment, the second groove 136 extends through the strip-shaped channel of the third side 133 of the base island 13.

[0040] It should be noted that setting the second groove 136 as a strip-shaped through-slot that penetrates the third side 133 of the base island 13 makes the processing of the second through-slot simpler and easier to operate, thereby saving processing costs.

[0041] like Figure 4 In an optional exemplary embodiment, the second groove 136 includes a first groove 1361 and a second groove 1362. The second groove 1362 is located at the bottom of the first groove 1361, and the first groove 1361 communicates with the second groove 1362. The overall width of the second groove 1362 is smaller than that of the first groove 1361.

[0042] It should be noted that the second groove 136 is configured to include a first groove 1361 and a second groove 1362. The second groove 1362 is located at the bottom of the first groove 1361, and the first groove 1361 and the second groove 1362 are connected. The overall width of the second groove 1362 is smaller than that of the first groove 1361. This effectively increases the contact surface 1372 of the second groove 136, resulting in a larger contact surface between the molding compound and the second groove 136 after solidification. This makes the connection between the entire molding compound and the lead frame 10 more secure, preventing it from falling off during subsequent transportation or use. Consequently, the internal structure of the chip is better protected, and its service life is improved.

[0043] In an optional exemplary embodiment, the second stepped groove 1362 has a trapezoidal cross-section, and the width of the second stepped groove 1362 gradually decreases along the direction close to the first stepped groove 1361.

[0044] It should be noted that the cross-section of the second groove 1362 is trapezoidal, and the width of the second groove 1362 gradually decreases along the direction close to the first groove 1361. This can further increase the connection strength between the molding compound and the base island 13. When the molding compound is filled into the second groove 1362 and solidifies, due to the structural characteristics of the second groove 1362, the molding compound is trapped in the second groove 1362, thereby making the connection between the molding compound and the base island 13 more secure.

[0045] The beneficial effects of the lead frame 10 provided in this embodiment are:

[0046] The encapsulation material in the first groove 135 and the second groove 136 is stably connected to the base island 13, thereby increasing the reliability and stability of the encapsulation.

[0047] This embodiment also provides a lead frame array 20, such as Figure 5 As shown. The lead frame array 20 includes a plurality of the aforementioned lead frames 10; the plurality of lead frames 10 are arranged in an array and connected as a whole. The lead frame array 20 is formed by cutting the aforementioned lead frames 10. Preferably, as Figure 5 The lead frame array 20 is in the form of a two-row, multi-column array.

[0048] This embodiment also provides a package comprising the aforementioned lead frame 10, a wafer, and a molding compound; wherein the wafer is disposed on the front side of the base island 13; the first groove 135 and the second groove 136 on the front side of the base island 13 are filled with the molding compound, and the back side of the base island 13 and a portion of the pins 15 are exposed outside the molding compound; by exposing a portion of the area, heat dissipation performance can be improved.

[0049] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A lead frame, characterized in that, Includes the frame body, base island, and pins; The base island is disposed on the frame body; The base island has a first side, a second side, a third side, and a fourth side; wherein the first side and the second side are arranged opposite to each other, and the third side and the fourth side are arranged opposite to each other; The first side and the second side are respectively provided with a first groove, the third side is provided with a second groove, and the pin is located close to the fourth side; Both the first groove and the second groove are disposed on the front side of the base island and are used to fill the molding material; The second groove includes a first groove and a second groove. The second groove is located at the bottom of the first groove, and the first groove and the second groove are connected. The overall width of the second groove is smaller than that of the first groove. The second groove has a trapezoidal cross-section, and its width gradually decreases along the direction close to the first groove.

2. The lead frame according to claim 1, characterized in that: The first side of the base island has at least two spaced-apart first grooves; The second side of the base island has at least two spaced-apart first grooves.

3. The lead frame according to claim 2, characterized in that: The first groove on the first side and the first groove on the second side are arranged opposite to each other.

4. The lead frame according to claim 2, characterized in that: The first side and the second side of the base island are respectively provided with protrusions extending to both sides, and the protrusions and the sidewalls of the base island form the first groove.

5. The lead frame according to claim 4, characterized in that: The boss has a groove surface and a connecting surface; the groove surface is a horizontal surface, and the groove surface and the first sidewall of the base island form an L-shaped first groove. The connecting surface extends toward the side away from the first groove and connects to the second sidewall of the base island; the connecting surface is convex arc-shaped; the second sidewall on the same side protrudes outward relative to the first sidewall.

6. The lead frame according to any one of claims 1-5, characterized in that: The second groove is a strip-shaped through-slot that penetrates the third side of the base island.

7. A lead frame array, characterized in that: It includes multiple lead frames as described in any one of claims 1-6; the multiple lead frames are connected to form a single unit.

8. A package, characterized in that, The package includes a lead frame, a wafer, and a molding compound as described in any one of claims 1-6; The wafer is disposed on the front side of the base island; the first and second grooves on the front side of the base island are filled with the molding compound, and the back side of the base island and a portion of the pins are exposed outside the molding compound.

Images