Lead frame for chip packaging

Abstract

The utility model relates to the technical field of chip packaging, in particular to a lead frame for chip packaging. Comprising a lead frame, a plurality of core carrying plates are arranged on the lead frame, a cutting separation line is arranged between every two adjacent core carrying plates, chip assemblies are arranged on the core carrying plates, plastic package materials are laid on the two sides of the lead frame, lead pins and a plurality of lead pins are arranged on the core carrying plates, a plurality of first grooves are formed in one side of each core carrying plate, and a plurality of second grooves are formed in the other side of each core carrying plate. A rectangular groove is formed in the side, away from the terminal pins, of the core carrying plate, a plurality of second grooves are formed in the inner wall of one side of the rectangular groove, and round holes are formed between the second grooves and the corresponding first grooves in a penetrating mode. Through the simple hole structure, firm packaging of the chip is facilitated, the problem that the plastic packaging material absorbs heat and is softened to be separated from the core carrying plate can be effectively avoided, the plastic packaging material can be prevented from being separated from the core carrying plate to form a gap, and the problem that damp air enters the gap to cause accelerated aging of the chip can be effectively prevented.

Description

TECHNICAL FIELD

[0001] The utility model relates to chip packaging technical field, concretely is a lead frame for chip packaging. BACKGROUND

[0002] With the continuous development of science and technology, the market demand for chips is increasing, a large number of chips are put into production, chip packaging needs to use lead frame, lead frame as the chip carrier of integrated circuit, is a kind of key structural member that realizes the electrical connection of chip internal circuit lead-out end and external lead by bonding material (gold wire, aluminum wire, copper wire), it plays the bridge role of connection with external wire, and most of semiconductor integrated blocks need to use lead frame, it is important basic material in electronic information industry, the prior art discloses a kind of lead frame for semiconductor chip packaging with the authorization announcement No.CN205666234U, including at least one lead frame plastic encapsulation unit, the lead frame plastic encapsulation unit is all with side frame around, the lead frame plastic encapsulation unit further includes several device units arranged at equal intervals, there is cutting path between adjacent device units, the device unit further includes chip bearing area and lead pipe pin, the chip bearing area is located in the center of device unit, the lead pipe pin is distributed in the periphery of chip bearing area;The cutting path has the feature pattern area for identification on it.The lead frame for semiconductor chip packaging avoids the mixing of a large amount of waste and a large number of device units, especially for small size chip products, reduces the process of separating waste and device units by manpower, and all remaining after cutting are device units, completely eliminate waste.

[0003] However, the existing lead frame for chip packaging is found in use that the packaging firmness of chip is limited, the plastic encapsulation material is prone to heat absorption and softening to separate from the chip carrier, which leads to the separation of the plastic encapsulation material and the chip carrier to form a gap, and the humid air is easy to enter the gap to cause the problem of accelerated aging of the chip in long-term use. UTILITY MODEL CONTENTS

[0004] In view of the above problems, the utility model aims at providing a lead frame for chip packaging, which can firmly package the chip, effectively prevent the plastic encapsulation material from softening and separating from the chip carrier due to heat absorption, prevent the plastic encapsulation material from separating from the chip carrier to form a gap, effectively prevent the humid air from entering the gap to cause the problem of accelerated aging of the chip, and solve the problems in the above background technology.

[0005] The utility model discloses a lead frame for chip packaging, which comprises a lead frame, a plurality of chip carrier plates arranged on the lead frame, cutting separation lines arranged between adjacent chip carrier plates, chip components arranged on the chip carrier plates, plastic sealing material arranged on both sides of the lead frame, lead pins and a plurality of lead tube pins arranged on the chip carrier plates, a plurality of first grooves arranged on one side of the chip carrier plates, a rectangular groove arranged on the side of the chip carrier plate away from the lead pins, a plurality of second grooves arranged on the inner wall of one side of the rectangular groove, and a circular hole penetrating between the second grooves and the corresponding first grooves.

[0006] In order to improve the accuracy of cutting and separating the chip units:

[0007] As a further improvement of the above technical solution, the lead frame further comprises a plurality of positioning clamping grooves arranged on the four peripheral edges of the lead frame, a positioning direction groove arranged on the inner wall of one side of the positioning clamping groove, and the positioning direction groove is opposite to the corresponding cutting separation line.

[0008] The improvement has the following beneficial effects: by such arrangement, the positioning of the plastic-sealed lead frame is facilitated, the accuracy of cutting and separating the chip units is effectively improved, and the yield of cutting is effectively improved.

[0009] In order to facilitate the conduction of the chip components:

[0010] As a further improvement of the above technical solution, the chip components are connected to the cutting separation line through the lead pins and the plurality of lead tube pins.

[0011] The improvement has the following beneficial effects: by such arrangement, the conduction of the chip components is facilitated.

[0012] In order to facilitate the plastic sealing material to fill the first grooves and the second grooves:

[0013] As a further improvement of the above technical solution, the first grooves are of a tapered structure, and the second grooves are of a circular structure.

[0014] The improvement has the following beneficial effects: by such arrangement, the plastic sealing material is facilitated to fill the first grooves and the second grooves.

[0015] In order to facilitate the cutting and separating of the chip units:

[0016] As a further improvement of the above technical solution, the plurality of chip carrier plates are arranged in a rectangular array, and the plurality of cutting separation lines are interwoven to form a grid structure.

[0017] The improvement has the following beneficial effects: by such arrangement, the cutting and separating of the chip units are facilitated.

[0018] In order to facilitate the plastic package effect of the lead frame and the chip:

[0019] As a further improvement of the above technical solution: the material of the plastic package material is epoxy resin, and the material of the lead frame is copper or copper-plated metal.

[0020] The beneficial effect of the improvement is that by such arrangement, the plastic package effect of the lead frame and the chip is facilitated.

[0021] In order to facilitate the positioning of the lead frame:

[0022] As a further improvement of the above technical solution: the positioning clamping groove and the positioning direction groove form a T-shaped structure.

[0023] The beneficial effect of the improvement is that by such arrangement, the positioning of the lead frame is facilitated.

[0024] The beneficial effect of the present utility model is that through the simple hole structure, the chip can be firmly packaged, the problem of heat absorption softening and separation of the plastic package material from the carrier board can be effectively avoided, the gap formed by the separation of the plastic package material from the carrier board can be prevented, and the problem of moisture air entering the gap to cause accelerated aging of the chip can be effectively prevented. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 It is a schematic diagram of the front view and sectional view structure of the present utility model;

[0026] Figure 2 It is a schematic diagram of the enlarged structure of part A in the present utility model;

[0027] Figure 3 It is a schematic diagram of the top view structure of the carrier board in the present utility model;

[0028] Figure 4 It is a schematic diagram of the bottom view structure of the carrier board in the present utility model;

[0029] Figure 5 It is a schematic diagram of the three-dimensional sectional view structure of the carrier board in the present utility model;

[0030] Figure 6 It is a schematic diagram of the side view sectional view structure of the carrier board in the present utility model.

[0031] In the figure: 1, lead frame; 2, cutting separation line; 3, carrier board; 4, chip assembly; 5, plastic package material; 6, lead foot; 7, lead pipe foot; 8, first groove; 9, rectangular groove; 10, second groove; 11, round hole; 12, positioning clamping groove; 13, positioning direction groove. DETAILED DESCRIPTION

[0032] To enable those skilled in the art to better understand the technical solution of this utility model, the present utility model will be described in detail below with reference to the accompanying drawings. The description in this part is only exemplary and explanatory, and should not be used to limit the scope of protection of this utility model in any way.

[0033] like Figures 1-6 As shown, a lead frame for chip packaging includes a lead frame 1, a plurality of carrier boards 3 on the lead frame 1, a cutting separation line 2 between adjacent carrier boards 3, a chip assembly 4 on the carrier board 3, molding compound 5 on both sides of the lead frame 1, lead pins 6 and a plurality of lead tubes 7 on the carrier board 3, a plurality of first grooves 8 on one side of the carrier board 3, a rectangular groove 9 on the side of the carrier board 3 away from the lead pins 6, and a plurality of second grooves 1 on the inner wall of one side of the rectangular groove 9. 0. A circular hole 11 extends through the second groove 10 and the corresponding first groove 8. This simple perforation structure facilitates secure chip encapsulation, effectively preventing the molding compound 5 from softening and detaching from the carrier board 3 due to heat absorption. This also prevents the molding compound 5 from separating from the carrier board 3 and forming gaps, thus effectively preventing humid air from entering the gaps and accelerating chip aging. The lead frame 1 also includes multiple positioning slots 12, which are located on the periphery of the lead frame 1. One inner wall of each positioning slot 12... A positioning guide groove 13 is provided, which is directly opposite the corresponding cutting separation line 2. This arrangement facilitates the positioning of the plastic-encapsulated lead frame, effectively improving the accuracy of cutting and separating the chip unit, thereby improving the yield rate of the cut chip. The chip assembly 4 is connected to the cutting separation line 2 through lead pins 6 and multiple lead tube pins 7, which facilitates the conductivity of the chip assembly 4. The first groove 8 has a conical structure, and the second groove 10 has a circular structure, which facilitates the filling of the first groove 8 and the second groove 10 with the molding compound 5. Multiple core carrier boards 3 are evenly arranged in a rectangular array, and multiple cutting separation lines 2 are interwoven to form a grid structure, which facilitates the cutting and separation of the chip unit. The molding compound 5 is made of epoxy resin, and the lead frame 1 is made of copper or copper-plated metal, which facilitates the molding effect of the lead frame and the chip. The positioning slot 12 and the positioning guide groove 13 form a T-shaped structure, which facilitates the positioning of the lead frame 1.

[0034] The working principle of the utility model is as follows: during production, first, the chip assembly 4 is placed on the corresponding carrier board 3, then the lead frame 1 is heat treated, so that the gold layer on the back of the chip assembly 4 melts and adheres to the carrier board 3, the die bonding is completed, then the pins of the chip assembly 4 are connected with the corresponding lead frame pins 7 through pressure welding inner leads, then the lead frame 1 is placed in a mold, the plastic sealing material 5 is pressed into the mold by hydraulic pressure, so that the plastic sealing material 5 is pressed with the lead frame 1, the chip assembly 4 and the lead frame 1 are plastic sealed, the plastic sealing material 5 is pressed into the plurality of rectangular grooves 9, part of the plastic sealing material 5 in the rectangular grooves 9 enters the second groove 10, the plastic sealing material 5 in the second groove 10 fills the first groove 8 through the round hole 11, so that the first groove 8, the second groove 10 and the round hole 11 are filled with the plastic sealing material 5, after the plastic sealing material 5 solidifies, the chip assembly 4 and the lead frame 1 are firmly plastic sealed together, through such setting, the chip can be firmly packaged, the problem that the plastic sealing material 5 absorbs heat, softens and separates from the carrier board 3 can be effectively avoided, so that the plastic sealing material 5 and the carrier board 3 can be prevented from separating to form a gap, so that the problem that humid air enters the gap to cause the chip to accelerate aging can be effectively prevented, when cutting the chip unit, first, the lead frame 1 is positioned through the two positioning clamping grooves 12, then the corresponding cutting separation line 2 is polished and cut, the accuracy of cutting is observed and calibrated through the positioning direction groove 13, through such setting, the plastic sealed lead frame can be positioned, the accuracy of cutting and separating the chip unit can be effectively improved, so that the yield of cutting can be effectively improved.

[0035] It should be noted that in this document, the terms "comprise", "comprising", or any other variant thereof are intended to cover non-exclusive inclusions, so that a process, method, article or device that includes a series of elements not only includes those elements, but also includes other elements not explicitly listed, or inherent to such a process, method, article or device. The principles and implementation modes of the utility model are described by specific examples, and the above example is only used to help understand the method and core idea of the utility model. The above is only the preferred embodiment of the utility model, it should be pointed out that due to the limited expression, there are infinite specific structures objectively, for ordinary skilled persons in the art, without departing from the principles of the utility model, a number of improvements, refinements or changes can be made, or the above technical features can be combined in a proper way, these improvements, refinements, changes or combinations, or without improvement, the concept and technical scheme of the utility model are directly applied to other occasions, which should be regarded as the protection scope of the utility model.

Claims

1. A lead frame for a chip package, comprising a lead frame (1), characterized in that: The lead frame (1) is provided with a plurality of core plate (3), the adjacent core plate (3) is provided with cutting separation line (2), the core plate (3) is provided with chip component (4), the both sides of the lead frame (1) are provided with plastic sealing material (5), the core plate (3) is provided with lead foot (6) and a plurality of lead tube foot (7), the core plate (3) is provided with a plurality of first recess (8) on one side, the core plate (3) is provided with rectangular recess (9) away from lead foot (6) on one side, a plurality of second recess (10) is provided on the inner wall of the one side of the rectangular recess (9), the second recess (10) and the corresponding first recess (8) are penetrated by round hole (11).

2. The lead frame for a chip package according to claim 1, wherein: The lead frame (1) further comprises a plurality of positioning clamping grooves (12), the positioning clamping groove (12) is provided on the four peripheral edges of the lead frame (1), the positioning clamping groove (12) is provided with positioning direction slot (13) on the inner wall of one side, the positioning direction slot (13) is opposite to the corresponding cutting separation line (2).

3. The lead frame for a chip package according to claim 1, wherein: The chip component (4) is connected with the cutting separation line (2) through the lead foot (6) and the plurality of lead tube foot (7).

4. The lead frame for a chip package according to claim 1, wherein: The first recess (8) is a tapered structure, and the second recess (10) is a circular structure.

5. The lead frame for a chip package according to claim 1, wherein: A plurality of the core plate (3) is evenly arranged in a rectangular array, and a plurality of the cutting separation line (2) is interlaced to form a grid structure.

6. The lead frame for a chip package according to claim 1, wherein: The material of the plastic sealing material (5) is epoxy resin, and the material of the lead frame (1) is copper or copper-plated metal.

7. The lead frame for a chip package according to claim 2, wherein: The positioning clamping groove (12) and the positioning direction slot (13) form a T-shaped structure.

Images