Chip lead frame structure and unit

Abstract

The utility model discloses a chip lead frame structure and a chip lead frame unit, the chip lead frame structure comprises a frame main body, two opposite sides of the frame main body are provided with outer pin interfaces, the frame main body is provided with a concave base island, and the surface of the frame main body is plated with a silver layer; the chip lead frame structure comprises a pressing plate and a chip lead frame structure body, a plurality of packaging grooves are evenly distributed in the pressing plate, and the chip lead frame structure body is arranged in the packaging grooves.

Description

Technical Field

[0001] The utility model relates to the technical field of integrated circuits, in particular to a chip lead frame structure and a unit. Background Art

[0002] SOT is a surface mount package, generally a small-outline transistor with 6 or less pins. In electronics, packaging not only plays a role in installing, fixing, sealing, protecting chips and enhancing electrical and thermal performance, but also connects the contacts on the chip to the pins of the package shell with wires, and these pins are connected to other devices through wires on the printed circuit board, thereby realizing the connection between the internal chip and the external circuit. Because the chip must be isolated from the outside world to prevent impurities in the air from corroding the chip circuit and causing a decrease in electrical performance. On the other hand, the packaged chip is also easier to install and transport.

[0003] In integrated packaging, the current chip lead frame structure has oxidation problems during the production process, and there is also a problem of poor welding quality due to base island vibration during the wire bonding process. In addition, the existing chip lead frame structure also faces the problem of weak bonding between the plastic sealing material and the pins after plastic sealing. Utility Model Content

[0004] In order to solve the above problems, the utility model provides a chip lead frame structure, and the specific technical solution is as follows:

[0005] It comprises a frame body, on two opposite sides of which external pin interfaces are arranged, and on the frame body there is an inwardly concave base island, and the surface of the part of the frame body where the base island is located is plated with a silver layer.

[0006] Furthermore, the external pin interface includes a first external pin interface, a second external pin interface, a third external pin interface and a fourth external pin interface.

[0007] Furthermore, the first external pin interface and the second external pin interface are directly connected to the chip disposed on the base island.

[0008] Furthermore, the third external pin interface and the fourth external pin interface are connected to the chip arranged on the base island through an internal pin interface, and the internal pin interface is provided with a silver layer on the main frame part.

[0009] Furthermore, the inner pin interface protrudes outward relative to the surface of the frame body, and a curved structure is formed between the inner pin interface and the corresponding outer pin interface.

[0010] Furthermore, a widening portion is provided on the outer side of the base island of the frame body, and the widening portion surrounds the remaining side edges of the base island excluding the side of the external pin interface.

[0011] Furthermore, on both sides of the widened portion relative to the side where the external pins are located, the widened width of the portion close to the external pin interface is wider than that of the portion far from the external pin interface.

[0012] Furthermore, the thickness of the widened portion is thinner than that of the base island portion.

[0013] The utility model also provides a chip lead frame unit, comprising a pressing plate and the chip lead frame structure described above, wherein the pressing plate is evenly provided with a plurality of packaging grooves, and the chip lead frame structure is placed in the packaging grooves.

[0014] The beneficial effects of the utility model are as follows:

[0015] The chip lead frame structure of the utility model has a base island of the frame body and a surface of a portion where an inner pin interface is located, thereby preventing oxidation thereof during the production process; the inner pin is arranged as a bent structure outwardly relative to the frame body, thereby increasing the spacing with the base island, reducing the capacitance effect between different electrodes, increasing the bonding force between the plastic sealing material and the pin after plastic sealing, preventing the pin from being delaminated, and preventing the pin from being pulled out of the plastic sealing body during rib cutting and forming; a widening portion is arranged outside the base island of the frame body, thereby facilitating pressing by a pressing plate during packaging, reducing vibration of the base island during wire bonding (welding), and ensuring welding quality; at the same time, the widening portion is thinner than the base island portion, thereby increasing the bonding force between the plastic sealing material and the base island after plastic sealing. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is an overall schematic diagram of the framework structure of Example 1.

[0017] Figure 2 It is an overall schematic diagram of the framework structure of Example 2.

[0018] Figure 3 It is a side structural diagram of the frame structure of Example 2.

[0019] Explanation of the figure numbers: 1-frame body, 2-first external pin interface, 3-second external pin interface, 4-third external pin interface, 5-fourth external pin interface, 6-base island, 7-widened part, 8-inner pin interface. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. The components of the embodiments of the utility model described and shown in the drawings here can be arranged and designed in various different configurations. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0021] In the description of the embodiments of the present utility model, it should be noted that the indicated orientation or position relationship is based on the orientation or position relationship shown in the accompanying drawings, or the orientation or position relationship in which the utility model product is usually placed when in use, or the orientation or position relationship commonly understood by those skilled in the art, or the orientation or position relationship in which the utility model product is usually placed when in use, which is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first" and "second" are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0022] In the description of the embodiments of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set" and "connection" 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 direct connection, or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0023] Example 1

[0024] Embodiment 1 of the present utility model discloses a chip lead frame structure, such as Figure 1 As shown, the specific structure is as follows:

[0025] It comprises a frame body 1, on two opposite sides of which external pin interfaces are arranged, and on the frame body 1 there is an inwardly concave base island 6, and the surface of the portion of the frame body 1 where the base island 6 is located is plated with a silver layer.

[0026] The silver layer on the surface of the frame body 1 avoids oxidation problems that may occur during the production process of the frame.

[0027] The base island 6 is used to place a chip, and the heat generated by the chip is discharged through the base island 6 .

[0028] In this embodiment, the external pin interface includes a first external pin interface 2, a second external pin interface 3, a third external pin interface 4 and a fourth external pin interface 5;

[0029] In this embodiment, the first external pin interface 2 and the second external pin interface 3 are directly connected to the chip disposed on the base island 6 .

[0030] In this embodiment, the third external pin interface 4 and the fourth external pin interface 5 are connected to the chip arranged on the base island 6 through the arranged internal pin interface 8 .

[0031] Specifically, the inner pin interface 8 connects the chip with the corresponding outer pin interface through a wire.

[0032] In this embodiment, the inner pin interface 8 is provided with a silver layer on the lateral portion of the frame body 1 .

[0033] Based on the architecture of the above-mentioned lead frame, according to actual conditions, two external pin interfaces can be added on the side of the first external pin interface 2 and the second external pin interface 3 to directly connect to the chip, and two external pin interfaces can be added on the side of the third external pin interface 4 and the fourth external pin interface 5 to connect to the chip through the internal pin interface.

[0034] like Figure 3 As shown, in this embodiment, the inner pin interface 8 protrudes outward relative to the surface of the frame body 1, and a curved structure is formed between the inner pin interface 8 and the corresponding outer pin interface.

[0035] Based on the curved structure of the inner pin interface 8, the distance from the base island 6 is increased, thereby reducing the capacitance effect between different electrodes; at the same time, the bonding force between the plastic encapsulation material and the pins after plastic encapsulation is increased to prevent the pins from being delaminated and reduce the pins from being pulled out of the plastic encapsulation body during rib cutting and forming.

[0036] Example 2

[0037] Embodiment 2 of the present utility model discloses a chip lead frame structure, such as Figure 2 As shown, the specific structure is as follows:

[0038] It comprises a frame body 1 , on two opposite sides of which external pin interfaces are arranged, on which a concave base island 6 is arranged, and the surface of the frame body 1 is plated with a silver layer.

[0039] The silver layer on the surface of the frame body 1 avoids oxidation problems that may occur during the production process of the frame.

[0040] The base island 6 is used to place a chip, and the heat generated by the chip is discharged through the base island 6 .

[0041] In this embodiment, the external pin interface includes a first external pin interface 2, a second external pin interface 3, a third external pin interface 4 and a fourth external pin interface 5;

[0042] In this embodiment, the first external pin interface 2 and the second external pin interface 3 are directly connected to the chip disposed on the base island 6 .

[0043] In this embodiment, the third external pin interface 4 and the fourth external pin interface 5 are connected to the chip arranged on the base island 6 through the arranged internal pin interface 8 .

[0044] Specifically, the inner pin interface 8 connects the chip with the corresponding outer pin interface through a wire.

[0045] Based on the architecture of the above-mentioned lead frame, according to actual conditions, two external pin interfaces can be added on the side of the first external pin interface 2 and the second external pin interface 3 to directly connect to the chip, and two external pin interfaces can be added on the side of the third external pin interface 4 and the fourth external pin interface 5 to connect to the chip through the internal pin interface.

[0046] like Figure 3 As shown, in this embodiment, the inner pin interface 8 protrudes outward relative to the surface of the frame body 1, and a curved structure is formed between the inner pin interface 8 and the corresponding outer pin interface.

[0047] Based on the curved structure of the inner pin interface 8, the distance from the base island 6 is increased, thereby reducing the capacitance effect between different electrodes; at the same time, the bonding force between the plastic encapsulation material and the pins after plastic encapsulation is increased to prevent the pins from being delaminated and reduce the pins from being pulled out of the plastic encapsulation body during rib cutting and forming.

[0048] In this embodiment, a widening portion 7 is provided on the outer side of the base island 6 of the frame body 1, that is, Figure 2 The dotted line extension portion of the base island 6, the widened portion 7 surrounds the base island 6 except the remaining side edges of the external pin interface side.

[0049] The widened portion 7 disposed outside the base island 6 of the frame body 1 is convenient for pressing by a pressing plate, thereby reducing vibration of the base island 6 during the wire bonding (welding) process and avoiding affecting welding quality.

[0050] like Figure 3 As shown, in this embodiment, the width of the widened portion 7 on both sides of the side where the external pins are located is wider at the portion close to the external pin interface than at the portion away from the external pin interface;

[0051] Specifically, the thickness of the widened portion 7 is thinner than that of the base island 6, that is, the dotted line extension portion of the base island 6 is hollowed out (thinned), which can increase the bonding force between the molding material and the base island 6 after molding and prevent delamination.

[0052] Example 3

[0053] Embodiment 3 of the present utility model discloses a chip lead frame unit, the specific structure of which is as follows:

[0054] It comprises a pressing plate and the chip lead frame structure described in the above-mentioned embodiment 1 or 2, wherein the pressing plate is evenly provided with a plurality of packaging grooves, and the chip lead frame structure is placed in the packaging grooves.

[0055] The above description is only an embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A chip lead frame structure, characterized in that: It comprises a frame body, on two opposite sides of which external pin interfaces are arranged, and on the frame body there is an inwardly concave base island, and the surface of the part of the frame body where the base island is located is plated with a silver layer.

2. The chip lead frame structure according to claim 1, characterized in that: The external pin interface includes a first external pin interface, a second external pin interface, a third external pin interface and a fourth external pin interface.

3. The chip lead frame structure according to claim 2, characterized in that: The first external pin interface and the second external pin interface are directly connected to the chip disposed on the base island.

4. The chip lead frame structure according to claim 2, characterized in that: The third external pin interface and the fourth external pin interface are connected to the chip arranged on the base island through the arranged internal pin interface.

5. The chip lead frame structure according to claim 4, characterized in that: The inner pin interface protrudes outward relative to the surface of the frame body, and a curved structure is formed between the inner pin interface and the corresponding outer pin interface.

6. The chip lead frame structure according to claim 1, characterized in that: A widening portion is provided on the outer side of the base island of the frame body, and the widening portion surrounds the remaining side edges of the base island except the side of the external pin interface.

7. The chip lead frame structure according to claim 6, characterized in that: The widened portion is wider at both sides of the side where the external pin is located, in the portion close to the external pin interface than in the portion far from the external pin interface.

8. The chip lead frame structure according to claim 7, characterized in that: The thickness of the widened portion is thinner than that of the base island portion.

9. A chip lead frame unit, characterized in that: It comprises a pressing plate and a chip lead frame structure as claimed in any one of claims 1 to 8, wherein the pressing plate is evenly provided with a plurality of packaging grooves, and the chip lead frame structure is placed in the packaging grooves.

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