SOT89 frame structure for preventing plastic package layering

Abstract

The utility model discloses an SOT89 frame structure for preventing plastic package layering, which comprises a frame substrate and a plurality of frame units distributed on the frame substrate in an array, the plurality of frame units are arranged in even rows along the width direction of the frame substrate, a connecting rib is arranged on the frame substrate between every two rows of frame units, and the connecting rib is arranged on the frame substrate between every two rows of frame units. The side, close to the connecting rib, of each frame unit is provided with a cooling fin, the two opposite cooling fins and the connecting rib are integrally formed, a first hollowed-out groove and a second hollowed-out groove which are arranged in a central symmetry mode are formed between the two opposite cooling fins, and a supporting plate is arranged between the first hollowed-out groove and the second hollowed-out groove. According to the utility model, the frame substrate can be prevented from being distorted and deformed during demolding, so that the plastic package body and the frame substrate are prevented from being cracked and layered.

Description

Technical Field

[0001] The utility model relates to the technical field of integrated circuit packaging, and particularly relates to an SOT89 frame structure for preventing plastic package delamination. Background Art

[0002] When integrated circuits are packaged, a lead frame structure is required. Common frame structures include DIP, SOP, SOT, DFN, QFN, etc. The SOT89 frame structure is one of the widely used frame structures on the market. It mainly includes a frame substrate and several frame units evenly arranged on the frame substrate. The chip is mounted at the frame unit, and then the frame substrate with the mounted chip is placed in a mold to form a plastic package. When demolding, the ejector pins on the mold push the frame substrate to separate the plastic package from the mold.

[0003] Nowadays, as the density of the frame units on the frame substrate is getting higher and higher, the contact area between the plastic package and the mold on a single frame substrate also increases. During demolding, it is easy to cause the problem of distortion and deformation of the frame substrate, resulting in the phenomenon of tearing and delamination between the plastic package and the frame substrate. Summary of the Utility Model

[0004] Aiming at the deficiencies of the existing technology, the utility model provides an SOT89 frame structure for preventing plastic package delamination, which can avoid the distortion and deformation of the frame substrate during demolding, thereby preventing the tearing and delamination between the plastic package and the frame substrate.

[0005] To achieve the above object, the utility model adopts the following technical solutions:

[0006] An SOT89 frame structure for preventing plastic package delamination includes a frame substrate and several frame units arrayed on the frame substrate. The several frame units are arranged in an even number of rows along the width direction of the frame substrate. A connecting rib is provided on the frame substrate between every two rows of the frame units. Each frame unit has a heat sink on one side close to the connecting rib. The two opposite heat sinks are integrally formed with the connecting rib, and a first hollow groove and a second hollow groove are provided between the two opposite heat sinks in a centrosymmetric manner. A support plate is arranged between the first hollow groove and the second hollow groove. During demolding, the auxiliary demolding ejector pin on the mold pushes the support plate.

[0007] By arranging an even number of frame units on the frame substrate, a connecting rib is arranged on the frame substrate between every two rows of frame units. A heat sink is provided on one side of each frame unit close to the connecting rib. The two opposite heat sinks are integrally formed with the connecting rib. A first hollow-out groove and a second hollow-out groove which are centrosymmetrically arranged are provided between the two opposite heat sinks. A support plate is provided between the first hollow-out groove and the second hollow-out groove. During demolding, an auxiliary demolding ejector pin on the mold pushes the support plate. The first hollow-out groove and the second hollow-out groove are used to release the stress between the frame substrate and the encapsulant, so that the frame substrate can be prevented from being distorted and deformed during demolding, and further the encapsulant and the frame substrate can be prevented from being pulled apart and delaminated.

[0008] As a preferred solution, the length A of the frame substrate is 272.3 ± 0.2 mm, the width B of the frame substrate is 100 ± 0.1 mm. 756 frame units are arranged in an array on the frame substrate. All the frame units are arranged in eighteen rows along the width direction of the frame substrate and forty-two columns along the length direction of the frame substrate.

[0009] As a preferred solution, the length A of the frame substrate is 272.3 ± 0.102 mm, the width B of the frame substrate is 100 ± 0.051 mm.

[0010] As a preferred solution, all the frame units are arranged in fourteen vertical columns along the length direction of the frame substrate. Each vertical column of the frame units is arranged in three groups along the width direction of the frame substrate. Each group of the frame units contains eighteen frame units.

[0011] As a preferred solution, a longitudinal stress release groove is provided between every two vertical columns of the frame units, and a transverse stress release groove is provided between every two groups of the frame units. Transverse stress release grooves are provided on both side edges in the width direction of the frame substrate.

[0012] As a preferred solution, both the first hollow-out groove and the second hollow-out groove are long grooves. The extending direction of the long groove is parallel to the length direction of the frame substrate. The first hollow-out groove is provided in one of the two opposite heat sinks, and the second hollow-out groove is provided in the other of the two opposite heat sinks.

[0013] As a preferred solution, both the first hollow-out groove and the second hollow-out groove are long grooves. The extending direction of the long groove is parallel to the width direction of the frame substrate. One end of the long groove extends to one of the two opposite heat sinks, and the other end of the long groove extends to the other of the two opposite heat sinks.

[0014] As a preferred solution, a part of one side of the support plate extends into the first hollow-out groove, and a part of the other side of the support plate extends into the second hollow-out groove.

[0015] As a preferred solution, there are two first hollow grooves, and the two first hollow grooves are spaced apart and arranged on one of the two opposite heat sinks. There are two second hollow grooves, and the two second hollow grooves are spaced apart and arranged on the other of the two opposite heat sinks.

[0016] As a preferred solution, one end of the first hollow groove away from the other first hollow groove penetrates through the side wall of the heat sink, and one end of the second hollow groove away from the other second hollow groove penetrates through the side wall of the heat sink.

[0017] Compared with the prior art, the present utility model has obvious advantages and beneficial effects. Specifically, by arranging an even number of rows of frame units on the frame substrate, a connecting rib is arranged on the frame substrate between every two rows of frame units. Each frame unit has a heat sink on one side close to the connecting rib. The two opposite heat sinks are integrally formed with the connecting rib, and a first hollow groove and a second hollow groove which are centrosymmetrically arranged are provided between the two opposite heat sinks. A support plate is arranged between the first hollow groove and the second hollow groove. During demolding, the auxiliary demolding ejector pin on the mold pushes the support plate. The first hollow groove and the second hollow groove are used to release the stress between the frame substrate and the plastic package body, so that the frame substrate can be prevented from being distorted and deformed during demolding, and further the plastic package body and the frame substrate can be prevented from being pulled and delaminated.

[0018] To more clearly illustrate the structural features, technical means, specific purposes and functions achieved by the present utility model, the following further detailed description of the present utility model will be made in conjunction with the drawings and specific embodiments: Description of the Drawings

[0019] Figure 1 is a schematic front view structure diagram of the frame substrate of the first embodiment of the present utility model;

[0020] Figure 2 is a schematic structure diagram of a single group of frame units of the first embodiment of the present utility model;

[0021] Figure 3 is a schematic structure diagram of the heat sink, the first hollow groove, the second hollow groove and the support plate of the first embodiment of the present utility model;

[0022] Figure 4 is a schematic diagram of the mold closing state of the first embodiment of the present utility model;

[0023] Figure 5 is a schematic diagram of the demolding state of the first embodiment of the present utility model.

[0024] Figure 6 is a schematic structure diagram of the heat sink, the first hollow groove, the second hollow groove and the support plate of the second embodiment of the present utility model;

[0025] Figure 7 It is a schematic diagram of the heat sink, the first hollow groove, the second hollow groove and the support plate of the third embodiment of the present utility model;

[0026] Figure 8 It is a schematic diagram of the heat sink, the first hollow groove, the second hollow groove and the support plate of the fourth embodiment of the present utility model;

[0027] Explanation of the attached drawing reference numerals:

[0028] 10 - Frame substrate; 11 - Connecting rib; 12 - Longitudinal stress relief groove; 13 - Transverse stress relief groove; 20 - Frame unit; 21 - Heat sink; 22 - First hollow groove; 23 - Second hollow groove; 24 - Support plate; 25 - Plastic package; 30 - Mold; 31 - Auxiliary demolding ejector pin. Detailed implementation manners

[0029] In the description of the present utility model, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the utility model and simplifying the description, rather than indicating or implying that the indicated position or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present utility model.

[0030] In the description of the present utility model, it should be noted that unless otherwise clearly specified and defined, the terms "installed", "connected", "connected" should be understood in a broad sense. For example, it 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 directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.

[0031] As Figures 1-5 shown, the present utility model discloses an SOT89 frame structure for preventing plastic package delamination, including a frame substrate 10 and a plurality of frame units 20 arrayed on the frame substrate 10, and the plurality of frame units 20 are arranged in an even number of rows along the width direction of the frame substrate 10.

[0032] A connecting rib 11 is provided on the frame substrate 10 between every two rows of the frame units 20. Each side of the frame unit 20 close to the connecting rib 11 has a heat sink 21. The two opposite heat sinks 21 are integrally formed with the connecting rib 11. A first hollow groove 22 and a second hollow groove 23 which are centrosymmetrically arranged are provided between the two opposite heat sinks 21. A support plate 24 is provided between the first hollow groove 22 and the second hollow groove 23. During demolding, the auxiliary demolding ejector pin 31 on the mold pushes the support plate 24, and the frame demolding ejector pins (not shown) on both sides of the mold push the two side edges in the width direction of the frame substrate 10.

[0033] The length A of the frame substrate 10 is 272.3 ± 0.2 mm, the width B of the frame substrate 10 is 100 ± 0.1 mm. 756 frame units 20 are arranged in an array on the frame substrate 10. All the frame units 20 are arranged in eighteen rows along the width direction of the frame substrate 10 and forty-two columns along the length direction of the frame substrate 10. Specifically, the length A of the frame substrate 10 is 272.3 ± 0.102 mm, and the width B of the frame substrate 10 is 100 ± 0.051 mm. By setting the frame substrate 10 with a length A of 272.3 ± 0.2 mm and a width B of 100 ± 0.1 mm, and arranging 756 frame units 20 in eighteen rows and forty-two columns on the frame substrate 10, when adopting the structure of the first hollow groove 22, the second hollow groove 23 and the support plate 24, the demolding requirements of the ultra-high density SOT89 frame structure can be met, and the plastic package 25 and the frame substrate 10 can be prevented from being torn and delaminated.

[0034] All the frame units 20 are arranged in fourteen longitudinal rows along the length direction of the frame substrate 10. Each longitudinal row of the frame units 20 is arranged in three groups along the width direction of the frame substrate 10. Each group of the frame units 20 contains eighteen frame units 20. A longitudinal stress relief groove 12 is provided between every two longitudinal rows of the frame units 20, and a transverse stress relief groove 13 is provided between every two groups of the frame units 20. Transverse stress relief grooves 13 are provided on both side edges in the width direction of the frame substrate 10.

[0035] Both the first hollow groove 22 and the second hollow groove 23 are long grooves. The extending direction of the long groove is parallel to the length direction of the frame substrate 10. The first hollow groove 22 is provided in one of the two opposite heat sinks 21, and the second hollow groove 23 is provided in the other of the two opposite heat sinks 21. By adopting the first hollow groove 22 and the second hollow groove 23 with a long groove structure, the long groove is more beneficial to releasing the stress between the frame substrate 10 and the plastic package 25, and reducing the warping degree of the frame substrate 10 after plastic encapsulation.

[0036] One side part of the support plate 24 extends into the first hollow groove 22, and the other side part of the support plate 24 extends into the second hollow groove 23. By arranging the two sides of the support plate 24 to extend into the first hollow groove 22 and the second hollow groove 23 respectively, the area of the support plate 24 is made larger, leaving enough working space for the auxiliary demolding ejector pin, which is beneficial for the auxiliary demolding ejector pin to push the support plate 24 to smoothly demold the plastic package 25 and prevent the plastic package 25 from being torn and delaminated from the frame substrate 10.

[0037] As Figure 6 shown, in the second embodiment, the difference from the first embodiment is that both the first hollow groove 22 and the second hollow groove 23 are long grooves, the extending direction of the long groove is parallel to the width direction of the frame substrate 10, one end of the long groove extends to one of the two opposite heat sinks 21, and the other end of the long groove extends to the other of the two opposite heat sinks 21.

[0038] As Figure 7 shown, in the third embodiment, the difference from the first embodiment is that there are two first hollow grooves 22, and the two first hollow grooves 22 are arranged at intervals on one of the two opposite heat sinks 21, there are two second hollow grooves 23, and the two second hollow grooves 23 are arranged at intervals on the other of the two opposite heat sinks 21. By adopting two first hollow grooves 22 arranged at intervals and two second hollow grooves 23 arranged at intervals, it is beneficial to disperse the internal stress of the frame substrate 10, avoid stress concentration, better release the stress between the frame substrate 10 and the plastic package 25, and reduce the warping degree of the frame substrate 10 after plastic encapsulation.

[0039] As Figure 8 shown, in the fourth embodiment, the difference from the third embodiment is that one end of the first hollow groove 22 far from the other first hollow groove 22 penetrates the side wall of the heat sink 21, and one end of the second hollow groove 23 far from the other second hollow groove 23 penetrates the side wall of the heat sink 21.

[0040] In summary, in the present utility model, even rows of frame units 20 are arranged on the frame substrate 10, a connecting rib 11 is arranged on the frame substrate 10 between every two rows of frame units 20, each frame unit 20 has a heat sink 21 on one side close to the connecting rib 11, two opposite heat sinks 21 are integrally formed with the connecting rib 11, and a first hollow groove 22 and a second hollow groove 23 which are centrosymmetrically arranged are arranged between the two opposite heat sinks 21. A support plate 24 is arranged between the first hollow groove 22 and the second hollow groove 23. During demolding, the auxiliary demolding ejector pin 31 on the mold pushes the support plate 24. The first hollow groove 22 and the second hollow groove 23 are used to release the stress between the frame substrate 10 and the encapsulant 25, so that the frame substrate 10 can be prevented from being distorted and deformed during demolding, and further the encapsulant 25 and the frame substrate 10 can be prevented from being torn and delaminated.

[0041] The above are only the preferred embodiments of the present utility model, and are not intended to limit the present utility model. Therefore, any modifications, equivalent replacements, improvements, etc. made to the above embodiments according to the technical reality of the present utility model still fall within the scope of the technical solution of the present utility model.

Claims

1. A SOT89 frame structure for preventing plastic packaging delamination, characterized in that: It comprises a frame substrate, and a plurality of frame units arrayed on the frame substrate, wherein the plurality of frame units are arranged in an even number of rows along a width direction of the frame substrate; A connecting rib is provided on the frame substrate between every two rows of frame units, and each frame unit has a heat sink on one side close to the connecting rib. Two opposite heat sinks are integrally formed with the connecting rib, and a first hollow groove and a second hollow groove are provided between the two opposite heat sinks in a centrally symmetrical manner. A support plate is provided between the first hollow groove and the second hollow groove. During demolding, the auxiliary demolding pin on the mold pushes the support plate.

2. The SOT89 frame structure for preventing plastic packaging delamination according to claim 1, characterized in that: The length A of the frame substrate is 272.3±0.2 mm, the width B of the frame substrate is 100±0.1 mm, and 756 frame units are arrayed on the frame substrate. All the frame units are arranged in eighteen rows along the width direction of the frame substrate and in forty-two columns along the length direction of the frame substrate.

3. The SOT89 frame structure for preventing plastic packaging delamination according to claim 2, characterized in that: The length A of the frame substrate is 272.3±0.102 mm, and the width B of the frame substrate is 100±0.051 mm.

4. The SOT89 frame structure for preventing plastic packaging delamination according to claim 2, characterized in that: All the frame units are arranged into fourteen columns along the length direction of the frame substrate, and the frame units in each column are arranged into three groups along the width direction of the frame substrate, and each group of the frame units includes eighteen frame units.

5. The SOT89 frame structure for preventing plastic packaging delamination according to claim 4, characterized in that: A longitudinal stress release groove is provided between every two longitudinal frame units, a transverse stress release groove is provided between every two groups of frame units, and transverse stress release grooves are provided on both side edges in the width direction of the frame substrate.

6. The SOT89 frame structure for preventing plastic packaging delamination according to claim 1, characterized in that: The first hollow groove and the second hollow groove are both long grooves, and the extension direction of the long groove is parallel to the length direction of the frame substrate. The first hollow groove is provided in one of the two opposite heat sinks, and the second hollow groove is provided in the other of the two opposite heat sinks.

7. The SOT89 frame structure for preventing plastic packaging delamination according to claim 1, characterized in that: The first hollow groove and the second hollow groove are both long grooves, the extension direction of the long groove is parallel to the width direction of the frame substrate, one end of the long groove extends to one of the two opposite heat sinks, and the other end of the long groove extends to the other of the two opposite heat sinks.

8. The SOT89 frame structure for preventing plastic packaging delamination according to claim 6 or 7, characterized in that: One side portion of the support plate extends into the first hollow groove, and the other side portion of the support plate extends into the second hollow groove.

9. The SOT89 frame structure for preventing plastic packaging delamination according to claim 1, characterized in that: There are two first hollow grooves, and the two first hollow grooves are arranged at intervals on one of the two opposite heat sinks. There are two second hollow grooves, and the two second hollow grooves are arranged at intervals on the other of the two opposite heat sinks.

10. The SOT89 frame structure for preventing plastic packaging delamination according to claim 9, characterized in that: One end of the first hollow groove away from the other first hollow groove passes through the side wall of the heat sink, and one end of the second hollow groove away from the other second hollow groove passes through the side wall of the heat sink.

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