Lead frame

Abstract

The utility model relates to a lead frame, comprising a lead frame body, the lead frame body is provided with a lead frame unit, the lead frame unit is provided with a packaging area, the packaging area is provided with a base island, and the lead frame body extends at one side of the packaging area to form a first pin and a second pin. The width of the first pin is larger than that of the second pin, the first pin abuts against the base island, the second pin is electrically connected with the base island, and the first pin is of a hollow structure; according to the utility model, the second pin of the lead frame is directly and electrically connected with the base island, and the first pin is of the hollow structure, so that the distance between the base island and the lead frame is reduced, the total resistance of a circuit between the base island and the lead frame is reduced, and the circuit design rationality is improved.

Description

Technical Field

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

[0002] Leadframe is a metal structure used in semiconductor packaging, usually made of copper alloy, used to support the chip and connect the chip pins and external pins. The pins on the leadframe are connected to the pins of the chip through metal wires, and then connected to the external pins through the leadframe to achieve electrical connection and signal transmission. The leadframe is a part of the leadframe, which is used to connect the chip pins and external pins as an extension of the leadframe.

[0003] In the process of semiconductor packaging, the connection between the chip, lead frame and base island is completed through gold wire (WireBonding); the chip is placed on the packaging substrate so that the chip pins are aligned with the pads on the lead frame or base island; the gold wire is led out from the chip pins through a wire bonding machine, and then the gold wire is connected to the pads on the lead frame or base island by heat pressure, and then a metal bond is formed between the gold wire and the pin and pad by welding. The gold wire is firmly connected to the pin and pad through heat and pressure, and then the gold wire is cut to ensure that the length of the gold wire in the connecting part is appropriate and will not affect the performance of the package, and finally packaged.

[0004] However, in actual applications, if the gold wire is too long, it will increase the resistance of the circuit, causing increased signal transmission delay, affecting the stability and accuracy of the signal. In addition, too long gold wire will also increase the possibility of electromagnetic interference and affect the performance of the entire circuit. Therefore, a reasonable lead length when designing a circuit is very important to ensure the normal operation of the circuit. Utility Model Content

[0005] To this end, the technical problem to be solved by the utility model is to overcome the problem in the prior art that the length of the gold wire between the lead frame and the base island is too long, which leads to an increase in the resistance of the circuit and affects the signal transmission efficiency, and further provides a lead frame, which shortens the length of the gold wire between the base island and the lead frame, thereby reducing the resistance of the circuit between the base island and the lead frame.

[0006] In order to solve the above technical problems, the utility model provides a lead frame, comprising:

[0007] A lead frame body is provided with a lead frame unit, wherein the lead frame unit is provided with a packaging area, wherein the packaging area is provided with a base island, wherein the lead frame body extends on one side of the packaging area to form a first pin and a second pin, wherein the width of the first pin is greater than the width of the second pin, and the first pin abuts the base island, and the second pin is electrically connected to the base island, wherein the first pin is arranged as a hollow structure.

[0008] In an embodiment of the present invention, two opposite sides of the base island are connected to the lead frame body via connecting members.

[0009] In an embodiment of the present invention, the hollow structure is configured to be composed of a plurality of lead bodies extending from the lead frame body, and the plurality of lead bodies are equidistant and spaced apart.

[0010] In one embodiment of the present invention, at least six of the pin bodies are included.

[0011] In an embodiment of the present invention, the lengths and widths of the plurality of pin bodies are equal.

[0012] In an embodiment of the present invention, the thicknesses of the plurality of lead bodies, the second lead, and the lead frame body are equal.

[0013] In one embodiment of the present invention, the width of the second pin is at least equal to the sum of the widths of the two pin parts.

[0014] In an embodiment of the present invention, the lead frame is provided with a square packaging through hole in the packaging area, and the base island is located in the square packaging through hole.

[0015] In one embodiment of the present invention, a plurality of the lead frame units are included, the plurality of the lead frame units are arranged in an array, and the plurality of the lead frame units are all provided with the base island.

[0016] In an embodiment of the present invention, the lead frame body is provided with a plurality of heat dissipation holes and pins.

[0017] The above technical solution of the utility model has the following beneficial effects compared with the prior art:

[0018] The lead frame described in the utility model has a second pin extending from the lead frame to directly electrically connect to the base island, replacing the gold wire connection method, reducing the distance between the base island and the lead frame, and further reducing the total resistance between the base island and the lead frame; the first pin is set as a hollow structure, which can further reduce the total resistance of the lead frame on the basis of ensuring normal electrical connection, thereby improving the performance and efficiency of the circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to make the content of the utility model easier to understand, the utility model is further described in detail according to the specific embodiments of the utility model in combination with the accompanying drawings, wherein

[0020] Figure 1 It is a structural schematic diagram of a front view of a lead frame in a preferred embodiment of the utility model.

[0021] Explanation of the reference numerals in the specification: 1. lead frame body; 2. pin; 3. second pin; 4. heat dissipation hole; 5. pin separation; 6. gap; 7. base island; 8. connector; 9. packaging area. DETAILED DESCRIPTION

[0022] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0023] Example

[0024] Reference Figure 1 As shown, in one embodiment of the present utility model, a lead frame includes:

[0025] The lead frame body 1 is preferably made of a material with high conductivity and excellent heat dissipation, such as copper or copper alloy. The lead frame body 1 is provided with a lead frame unit, and the lead frame unit is provided with a packaging area 9. The packaging area 9 is provided with a base island 7. The chip is arranged on the base island 7, and the pins of the chip are connected to the pins of the base island 7 through gold wires. The lead frame body 1 extends on one side of the packaging area 9 to form a first pin and a second pin 3. The width of the first pin is greater than the width of the second pin 3, and the first pin abuts the base island 7 without being electrically connected to the pin of the base island 7. In other embodiments, The first pin is used to wait for the pin of the base island 7 to be electrically connected or to connect an external pin; the second pin 3 directly contacts the pin of the base island 7 to form an electrical connection, replacing the original solution of connecting the pin of the base island 7 and the pin of the lead frame body 1 through a gold wire, which not only shortens the distance between the base island 7 and the lead frame body 1, but also reduces the total resistance of the circuit, wherein the first pin is set to a hollow structure, that is, part of the material is cut away from the first pin to form a plurality of gaps 6, and the gaps 6 can avoid electrical connection, reduce the weight of the lead frame body 1, and reduce the resistance of the lead frame body 1.

[0026] In one embodiment of the present invention, referring to Figure 1As shown, the base island 7 is provided with a rectangular structure. In order to improve the structural stability of the base island 7, the opposite sides of the base island 7 are respectively connected to the lead frame body 1 through two non-conductive connectors 8 to prevent the base island 7 from being suspended in the air. Specifically, the two connectors 8 are provided on the left and right sides of the base island 7, and the lead frame units are provided on the front and back sides of the base island 7.

[0027] In one embodiment of the present invention, referring to Figure 1 As shown, the hollow structure is configured to be composed of a plurality of pin splits 5 extending from the lead frame body 1, and in order to improve the connection stability between the pins of the base island 7 and the lead frame body 1, the plurality of pin splits 5 are equidistant and spaced apart, and the pin splits 5 directly abut the base island 7.

[0028] In one embodiment of the present invention, referring to Figure 1 As shown, each lead frame Danyu includes at least eight pins, including the six pin segments 5 constituting the first pins and two pins constituting the second pins 3 and arranged in one piece.

[0029] In one embodiment of the present invention, referring to Figure 1 As shown, the lengths and widths of the plurality of pin bodies 5 are equal.

[0030] In one embodiment of the present invention, referring to Figure 1 As shown, the thicknesses of the plurality of pin bodies 5, the second pins 3 and the lead frame body 1 are equal, wherein the head of the second pin 3 is offset toward one side of the base island 7 relative to the head of the first pin, and the tail of the second pin 3 is offset toward one side of the base island 7 relative to the tail of the first pin.

[0031] In one embodiment of the present invention, referring to Figure 1 As shown, the width of the second pin 3 is at least equal to the sum of the widths of the two pin parts 5 .

[0032] In one embodiment of the present invention, referring to Figure 1 As shown, the lead frame is provided with a square packaging through hole in the packaging area 9, and the shape of the base island 7 matches the shape of the square packaging through hole, so that the base island 7 is just accommodated in the square packaging through hole, and the two side edges of the through hole are connected by a connector 8.

[0033] In one embodiment of the present invention, referring to Figure 1 As shown, the lead frame body 1 includes eight lead frame units, the eight lead frame units are arrayed in four rows and two columns, and each of the lead frame units is provided with the base island 7 .

[0034] In one embodiment of the present invention, referring to Figure 1As shown, the lead frame body 1 is provided with a plurality of heat dissipation holes 4 and pins, wherein the pins are arranged on both sides of the length direction of the lead frame body 1, the heat dissipation holes 4 are arranged as strip holes extending along the length direction of the lead frame body 1, and the plurality of heat dissipation holes 4 are distributed along the length direction of the lead frame, and at least one heat dissipation hole 4 is provided between every two lead frame units; the strip hole heat dissipation holes 4 can improve the heat dissipation efficiency of the lead frame, and the pins are used for transmitting electrical signals.

[0035] The working principle of the lead frame of the utility model is:

[0036] The two sides of the base island 7 are fixedly connected to the lead frame body 1 through the connecting piece 8, and then the chip is set on the base island 7 so that the chip pins are aligned with the first pin, the second pin 3 and the pad of the base island 7, and the pins of the chip and the pins of the base island 7 are connected by gold wires, and the pins of the base island 7 are directly electrically connected to the second pin 3 of the lead frame. Finally, the pins of the lead frame body 1 are connected to the external pins to complete the connection.

[0037] Obviously, the above embodiments are merely examples for the purpose of clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from these are still within the scope of protection of the invention of the utility model.

Claims

1. A lead frame, characterized in that: include, A lead frame body is provided with a lead frame unit, wherein the lead frame unit is provided with a packaging area, wherein the packaging area is provided with a base island, wherein the lead frame body extends on one side of the packaging area to form a first pin and a second pin, wherein the width of the first pin is greater than the width of the second pin, and the first pin abuts the base island, and the second pin is electrically connected to the base island, wherein the first pin is arranged as a hollow structure.

2. A lead frame according to claim 1, characterized in that: The opposite sides of the base island are connected to the lead frame body through connecting members.

3. The lead frame according to claim 1, characterized in that: The hollow structure is configured to be composed of a plurality of lead bodies extending from the lead frame body, and the plurality of lead bodies are equidistantly and spaced apart from each other.

4. A lead frame according to claim 3, characterized in that: At least six of the pin bodies are included.

5. The lead frame according to claim 3, characterized in that: The lengths and widths of the multiple pin bodies are equal.

6. The lead frame according to claim 3, characterized in that: The thicknesses of the plurality of lead bodies, the second lead, and the lead frame body are equal.

7. The lead frame according to claim 3, characterized in that: The width of the second pin is at least equal to the sum of the widths of the two pin parts.

8. The lead frame according to claim 1, characterized in that: The lead frame is provided with a square packaging through hole in the packaging area, and the base island is located in the square packaging through hole.

9. The lead frame according to claim 1, characterized in that: It comprises a plurality of lead frame units, the plurality of lead frame units are arranged in an array, and the plurality of lead frame units are each provided with the base island.

10. The lead frame according to claim 1, characterized in that: The lead frame body is provided with a plurality of heat dissipation holes and pins.

Images