Chip packaging system

Abstract

The invention relates to a chip packaging system which comprises a positioning platform, a carrier plate, a pressing plate and a wire bonding machine table. The positioning platform is provided with a flange structure, an adsorption structure and at least one thread breaking structure; the carrier plate is located above the positioning platform, a plurality of chip mounting structures used for fixing chips are attached to the carrier plate, and in the first state, the bottom surfaces of the chip mounting structures are higher than the positioning platform; in the second state, the bottom surface of the patch structure is in contact with the positioning platform and is adsorbed and fixed by the adsorption structure, and the chip is restrained on one side by the flange structure; the pressing plate is located above the carrier plate and can abut against the surface of the carrier plate. The wire bonding machine table is located above the pressing plate and can fix the first end of the wire to the chip and pull the second end of the wire to the wire breaking structure so that the wire can be cut off by the wire breaking structure. The chip carrying capacity of the carrier plate is improved, multi-station wire bonding operation can be carried out at the same time, and the chip positioning precision is improved.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor packaging, and in particular to a chip packaging system. Background Art

[0002] In the field of semiconductor packaging, chip packaging technology is a key link to ensure its performance and reliability. With the development of technology, packaging technology is also constantly improving to meet the needs of higher performance, smaller size and lower power consumption.

[0003] The packaging process includes the process of fixing the chip on the substrate, which can be achieved through materials such as epoxy resin, solder or metal paste. Bonding processes, such as wire bonding and flip chip bonding, are key steps in connecting the chip to the external circuit. The wire bonding process connects the chip and the substrate through metal wires (such as gold wires, silver wires, and copper wires), while flip chip bonding achieves connection through bumps formed on the chip pads.

[0004] Currently, the packaging of image sensor chips mainly adopts the wire bonding method, but the packaging cost is high and the packaging volume is large. Summary of the invention

[0005] In order to overcome the above shortcomings, the present invention provides a chip packaging system, which implements a new chip packaging process and can effectively solve the problems of high packaging cost and large packaging volume.

[0006] The chip packaging system comprises:

[0007] A positioning platform, comprising a retaining edge structure, an adsorption structure and at least one wire breaking structure, wherein the retaining edge structure is higher than a surface of the positioning platform;

[0008] A carrier plate is located above the positioning platform and includes a first state and a second state. The carrier plate is attached with a plurality of patch structures for fixing chips. In the first state, the bottom surface of the patch structure is higher than the positioning platform. At this time, the carrier plate can be driven to step in one direction. In the second state, the bottom surface of the patch structure contacts the positioning platform and is fixed by the adsorption structure, and the chip on the adsorbed patch structure is constrained to one side by the retaining edge structure.

[0009] A pressing plate, located above the carrier plate, the pressing plate can abut against the surface of the carrier plate, and the pressing plate includes a window portion for exposing a partial area of ​​the carrier plate;

[0010] A wire bonding machine is located above the pressure plate, and the wire bonding machine can pass through the window portion to fix the first end of the wire on the chip, and can pull the second end of the wire to the wire breaking structure to be cut by the wire breaking structure. This process is commonly known as wire bonding or wire bonding.

[0011] Furthermore, the carrier board also includes a plurality of hollow portions arranged in a periodic manner, a portion of each of the hollow portions is covered by the patch structure, and the adsorption structure can adsorb the bottom surface of the patch structure through the hollow portions.

[0012] Furthermore, the carrier board further comprises a plurality of marking parts arranged in a periodic manner, and the wire bonding machine comprises an identification part for identifying the marking part, and the identification part can determine the position of the chip according to the position of the marking part.

[0013] Furthermore, the marking parts are arranged on both sides of each hollow part.

[0014] Furthermore, the hollow parts are evenly arranged along the length direction and width direction of the carrier plate, the length direction is parallel to the stepping direction, and the width direction is perpendicular to the length direction.

[0015] Furthermore, at least four hollow portions are arranged along the width direction.

[0016] Furthermore, the width of the patch structure is smaller than the width of the chip, and both sides of the chip in the width direction protrude from the patch structure.

[0017] Furthermore, the patch structure is elastic.

[0018] Furthermore, the patch structure is a high temperature tape.

[0019] Furthermore, the first side of the adsorption structure and the second side opposite to the first side are both provided with the wire breaking structure, the second side is also provided with the edge retaining structure, and the direction from the first side to the second side is consistent with the stepping direction of the carrier.

[0020] Furthermore, the retaining edge structure includes a first surface and a second surface, wherein the first surface is a vertical surface for constraining the chip, and the second surface is an inclined surface for providing an avoidance path for the wire bonding machine to pull the wire to the wire breaking structure.

[0021] Furthermore, the adsorption structure includes: a vacuum pump and a negative pressure channel, the vacuum pump is connected to the negative pressure channel, and the negative pressure channel extends to the surface of the positioning platform.

[0022] Furthermore, the pressing plate further comprises: a pressing structure, which extends toward the surface direction of the positioning platform and is located at both sides of the window portion, and is used for abutting against the carrier plate.

[0023] The chip packaging system provided by the present invention can realize a new wire bonding process, improve the chip loading capacity of the carrier board, and realize an automated wire breaking process through a wire breaking structure.

[0024] The chip packaging system of the present invention can perform wire bonding operations at multiple stations simultaneously.

[0025] The chip position is automatically corrected by setting the retaining edge structure, thereby improving the positioning accuracy of the chip. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A structural cross-sectional view of a chip packaging system according to an embodiment of the present invention;

[0027] Figure 2 A top view of the structure of a chip packaging system according to an embodiment of the present invention;

[0028] Figure 3 for Figure 1 A detailed enlarged picture of the middle frame A;

[0029] Figure 4 for Figure 3 A magnified detail of the middle frame B;

[0030] Figure 5 A schematic structural diagram of a carrier board of a chip packaging system according to an embodiment of the present invention;

[0031] Figure 6 for Figure 5 A detailed enlarged view of the middle frame C;

[0032] Figure 7 FIG. 1 is a schematic structural diagram of a rib structure 101 of a chip packaging system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0033] The following is a further detailed description of a chip packaging system proposed by the present invention in combination with the accompanying drawings and specific embodiments. According to the following description, the advantages and features of the present invention will be clearer. It should be noted that the drawings are in a very simplified form and use non-precise proportions, which are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention. In order to make the purposes, features and advantages of the present invention more obvious and easy to understand, please refer to the accompanying drawings. It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention, so they have no technical substantive significance. Any structural modification, change in proportional relationship or adjustment of size, without affecting the effects that can be produced by the present invention and the purposes that can be achieved, should still fall within the scope of the technical content disclosed by the present invention.

[0034] Chip packaging is a key link in the semiconductor manufacturing process. It not only protects the chip from physical damage, but also ensures the electrical connection between the chip and the external circuit. The wire bonding step, also known as wire bonding, is an important step in chip packaging. Its main function is to connect the pins of the chip to the external circuit.

[0035] Chip packaging needs to consider many factors, such as chip heat dissipation, stability, material selection, environmental isolation, and cost considerations. In wire bonding packaging, commonly used wires include gold wire, silver alloy wire, palladium copper wire, and pure copper wire. The current wire bonding process includes the process of fixing the chip on the substrate, which can be made of materials such as epoxy resin, solder, or metal paste. The quality of the bonding process directly affects the electrical connection and heat dissipation performance of the chip.

[0036] The gold wire bonding process of the image sensor chip includes welding the two ends of the gold wire to the connection chip and the substrate respectively. This connection method has problems such as large packaging volume, high cost and strict packaging environment requirements.

[0037] The present invention adopts a new packaging method and provides a chip packaging system. The present invention divides the wire bonding process into two steps: welding and wire breaking. Welding refers to welding the first end of the wire to the chip, and wire breaking refers to cutting the wire and reserving a certain length for connection with the substrate circuit. The wire can be a gold wire, a silver wire, or a copper wire. The embodiment provided by the present invention uses an image sensor chip as an example. The image sensor chip is square, and wire bonding is required on both sides of the square.

[0038] See also Figure 1 and Figure 2 , Figure 1 shows a cross-sectional view of the chip packaging system, Figure 2 FIG. 4 shows a top view of the chip packaging system. Figure 1, 2 As shown, the chip packaging system includes: a positioning platform 11, a carrier 12, a pressing plate 13 and a wire bonding machine (not shown in the figure). The carrier 12 is used to fix the chip. The carrier 12 can be controlled by a program to step along a fixed direction on the positioning platform 11, and is fixed by the positioning platform 11 after stepping. The pressing plate 13 is used to press the carrier 12 onto the positioning platform 11, and the wire bonding machine can perform wire bonding on the chip on the fixed carrier 12. In some examples, the carrier 12 is separated from the positioning platform 11 during the stepping process.

[0039] The wiring process can be:

[0040] Initialization process of chip packaging system: after initialization, the positioning platform 11, carrier 12, pressing plate 13 and wire bonding machine are separated from each other, the platform 11 is located at the bottom, the carrier 12 is higher than the platform 11, and the pressing plate 13 and wire bonding machine are both higher than the carrier 12;

[0041] Stepping and positioning process of the carrier 12: the carrier 12 steps a certain distance along a fixed direction. When it reaches a fixed position, the wire bonding machine recognizes the chip on the carrier 12 and starts to prepare for wire bonding. Before wire bonding, the carrier 12 sinks and fits with the positioning platform 11. Then the pressing plate 13 presses down to press the carrier 12 onto the positioning platform 11.

[0042] The bonding process of the bonding machine: The bonding machine spits out the wire and welds it on the chip, then pulls the wire to the wire breaking position on the positioning platform and performs wire breaking, thus completing the bonding process of a chip. After the bonding is completed, the above initialization process and carrier positioning process can be repeated until all chips are bonded.

[0043] See also Figure 3 and Figure 4 , Figure 3 for Figure 1 A detailed enlarged picture of the middle frame A. Figure 4 for Figure 3 A detailed enlarged view of the middle frame B. The positioning platform 11 includes a retaining edge structure 101, an adsorption structure 102, and at least one wire breaking structure 103, wherein the retaining edge structure 101 is higher than the surface of the positioning platform 11. In this embodiment, since both opposite sides of the chip need to be wired, a wire breaking structure 103 is provided on both sides of the adsorption structure 102. The wire breaking structure 103 has a blade surface, and the wire bonding machine can pull the wire 15 to hit the blade surface and be cut off.

[0044] It should be noted that the present invention does not limit the number and position of the retaining edge structure 101, the adsorption structure 102 and the wire breaking structure 103, and the number and position can be flexibly set according to the number of chips on the carrier 12 and the wire bonding position of the chip. When the chip is fixed on the positioning platform 11, the chip is located on one side of the retaining edge structure 101 ( Figure 3 When the chip needs to be moved, the carrier 12 needs to rise relative to the positioning platform 11, and the chip is driven by the carrier 12 to move to the right, and then the carrier 12 sinks after moving to a predetermined position. After sinking, the chip on the carrier 12 is restricted to a fixed position by the retaining edge structure 101, and the adsorption structure 102 is located below the position. And, the carrier 12 is pressed tightly in cooperation with the pressing plate 13.

[0045] See also Figure 5 and Figure 6 , Figure 5 is a schematic structural diagram of the carrier board 12, Figure 6 for Figure 5 A detailed enlarged view of the middle frame C. When in use, the carrier 12 is located above the positioning platform. The carrier 12 is attached with a plurality of patch structures 104 for fixing the chip 14. The carrier 12 is controlled by a control program and may include a first state and a second state. In the first state, the bottom surface of the patch structure 104 is higher than the positioning platform 11. At this time, the carrier 12 can be driven to step in one direction, that is, the above-mentioned stepping to the right; in the second state, the bottom surface of the patch structure 104 contacts the positioning platform 11 and is adsorbed and fixed by the adsorption structure 102.

[0046] like Figure 2 , 3As shown, when in use, the pressing plate 13 is located above the carrier 12, and the pressing plate 13 can abut against the surface of the carrier 12. The pressing plate 13 includes a window portion 108 for exposing a partial area of ​​the carrier 12. The pressing plate 13 also includes: a downward pressing structure 109, which extends toward the surface direction of the positioning platform 11 and is located on both sides of the window portion 108, and is used to abut against the carrier 12. The wire bonding machine (not shown in the figure) is located above the pressing plate 13, and the wire bonding machine can pass through the window portion 108 to fix the first end of the wire on the chip 14, and can pull the second end of the wire to the wire breaking structure 103 to be cut by the wire breaking structure 103. After the wire is cut, one end is suspended in the air, and the other end is bonded to the chip 14. This process is also called a two-solder point suspended wire bonding process. After the two-solder point hanging wire bonding process, the chip is connected to the first end of the wire, and the second end of the wire is hanging. Such a chip can enter the next packaging process, that is, connecting the hanging end of the wire to the substrate. The wire can be a gold wire, a silver wire or a copper wire. The wire has a certain hardness after being cut, and the hanging end of the wire can be fixed on the substrate by solder paste or other welding methods.

[0047] Please continue reading Figure 5 , 6 , the carrier 12 also includes a plurality of hollow portions 105 arranged in a periodic manner, a portion of each of the hollow portions 105 is covered by the patch structure 104, and the adsorption structure 102 can adsorb the bottom surface of the patch structure 104 through the hollow portions 105. Further, the carrier 12 also includes a plurality of marking portions 106 arranged in a periodic manner, and the wire bonding machine includes an identification portion for identifying the marking portion, and the identification portion can determine the position of the chip 14 according to the position of the marking portion 106. The general setting method is: one hollow portion 105 corresponds to a group of marking portions 106, and the group of marking portions 106 can be two marking patterns, holes, grooves or protrusions diagonally arranged on both sides of the hollow portion 105, or other regular or irregular patterns that are easy to identify. In this embodiment, the marking portions 106 are arranged on both sides of each of the hollow portions 105.

[0048] In order to increase the bonding efficiency of the chip packaging system, the hollow portions 105 of the carrier 12 are evenly arranged along the length direction and width direction of the carrier, with 4 in the width direction and 12 in the length direction. The carrier 12 can carry 48 chips at the same time, and each step can bond 4 chips in the width direction, which greatly improves the bonding efficiency. In this example, the length direction is parallel to the stepping direction, and the width direction is perpendicular to the length direction. The number of the hollow portions 105 can also be greater than 48, and the arrangement is not limited to the above-mentioned 4 in the width direction.

[0049] In this embodiment, the width of the patch structure 104 is smaller than the width of the chip 14, and both sides of the chip 14 in the width direction protrude from the patch structure 104. The patch structure 104 can be made of an elastic material. The elastic material can produce a slight deformation in the plane where the surface of the carrier 12 is located. When the position of the chip 14 deviates, the sidewall structure contacts the side of the chip 14, and pushes the patch structure 104 connected to the chip to deform, thereby correcting the position of the chip 14. Preferably, the patch structure 104 is a high-temperature tape.

[0050] like Figure 7 As shown, a schematic diagram of the structure of the retaining edge structure 101 is shown. The retaining edge structure 101 described in this example includes a first surface 111 and a second surface 112. The first surface 111 is a vertical surface for constraining the chip 14, and the second surface 112 is an inclined surface for providing an avoidance path for the wire bonding machine to pull the wire 15 to the wire breaking structure 103. Since the wire 15 is relatively thin and the second end is suspended, if the retaining edge structure 101 has a protruding table or angle, it is easy to cause the wire 15 to deform or break. Taking this into consideration, the present invention sets the outer side surface (second surface) of the retaining edge structure 101 as an inclined surface to avoid the walking path of the wire.

[0051] In some embodiments, the first side of the adsorption structure 102 and the second side opposite to the first side are both provided with the breaking structure 103, and the second side is also provided with the retaining edge structure 101, and the direction from the first side to the second side is consistent with the stepping direction of the carrier 12.

[0052] Specifically, the adsorption structure 102 includes: a vacuum pump and a negative pressure channel, the vacuum pump is communicated with the negative pressure channel, and the negative pressure channel extends to the surface of the positioning platform.

[0053] In summary, the chip packaging system provided by the present invention can realize a new wire bonding process, improve the chip loading capacity of the carrier board, and realize an automated wire breaking process through the wire breaking structure.

[0054] Although the content of the present invention has been described in detail through the above preferred embodiments, it should be appreciated that the above description should not be considered as a limitation of the present invention. After reading the above content, it will be apparent to those skilled in the art that various modifications and substitutions of the present invention will occur. Therefore, the protection scope of the present invention should be limited by the appended claims.

Claims

1. A chip packaging system, characterized in that: include: A positioning platform, comprising a retaining edge structure, an adsorption structure and at least one wire breaking structure, wherein the retaining edge structure is higher than a surface of the positioning platform; A carrier plate is located above the positioning platform and includes a first state and a second state. The carrier plate is attached with a plurality of patch structures for fixing chips. In the first state, the bottom surface of the patch structure is higher than the positioning platform. At this time, the carrier plate can be driven to step in one direction. In the second state, the bottom surface of the patch structure contacts the positioning platform and is fixed by the adsorption structure, and the chip on the adsorbed patch structure is constrained to one side by the retaining edge structure. A pressing plate, located above the carrier plate, the pressing plate can abut against the surface of the carrier plate, and the pressing plate includes a window portion for exposing a partial area of ​​the carrier plate; The wire bonding machine is located above the pressing plate. The wire bonding machine can fix the first end of the wire on the chip through the window portion, and can pull the second end of the wire to the wire breaking structure to be cut off by the wire breaking structure.

2. The chip packaging system according to claim 1, characterized in that: The carrier board further includes a plurality of hollow portions arranged in a periodic manner, a portion of each of the hollow portions is covered by the patch structure, and the adsorption structure can adsorb the bottom surface of the patch structure through the hollow portions.

3. The chip packaging system according to claim 2, characterized in that: The carrier board further includes a plurality of marking parts arranged in a periodic manner, and the wire bonding machine includes an identification part for identifying the marking part, and the identification part can determine the position of the chip according to the position of the marking part.

4. The chip packaging system according to claim 3, characterized in that: The marking parts are arranged on both sides of each hollow part.

5. The chip packaging system according to claim 2, characterized in that: The hollow parts are evenly arranged along the length direction and the width direction of the carrier plate, the length direction is parallel to the stepping direction, and the width direction is perpendicular to the length direction.

6. The chip packaging system according to claim 5, characterized in that: At least four hollow portions are arranged along the width direction.

7. The chip packaging system according to claim 1, characterized in that: The width of the patch structure is smaller than the width of the chip, and both sides of the chip in the width direction protrude from the patch structure.

8. The chip packaging system according to claim 1, characterized in that: The patch structure is elastic.

9. The chip packaging system according to claim 8, characterized in that: The patch structure is a high temperature adhesive tape.

10. The chip packaging system according to claim 1, wherein: The first side of the adsorption structure and the second side opposite to the first side are both provided with the wire breaking structure, the second side is also provided with the edge retaining structure, and the direction from the first side to the second side is consistent with the stepping direction of the carrier.

11. The chip packaging system according to claim 1, characterized in that: The retaining edge structure includes a first surface and a second surface, wherein the first surface is a vertical surface for constraining the chip, and the second surface is an inclined surface for providing an avoidance path for the wire bonding machine to pull the wire to the wire breaking structure.

12. The chip packaging system according to claim 1, characterized in that: The adsorption structure comprises: a vacuum pump and a negative pressure channel, the vacuum pump is communicated with the negative pressure channel, and the negative pressure channel extends to the surface of the positioning platform.

13. The chip packaging system according to claim 1, wherein: The pressing plate further comprises: a pressing structure, which extends toward the surface direction of the positioning platform and is located at both sides of the window portion, and is used for abutting against the carrier plate.

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