阅读说明：本技术 一种适用于高密度高功率的封装结构及制造方法 (Packaging structure suitable for high-density high-power and manufacturing method ) 是由 徐健 曹立强 于 2019-09-25 设计创作，主要内容包括：本发明提供了一种适用于高密度高功率的封装结构及其制作方法,包括引线框架结构,引线框架结构具有散热结构,在边缘两侧制作封装引脚；在引线框架上表面中间固定转接板,转接板上下表面分布有走线,转接板边缘区域的焊盘与封装引脚通过导线连接；在转接板上表面安装芯片；对引线框架结构、转接板、芯片形成的整体结构进行塑封。(The invention provides a packaging structure suitable for high-density high-power and a manufacturing method thereof, wherein the packaging structure comprises a lead frame structure, wherein the lead frame structure is provided with a heat dissipation structure, and packaging pins are manufactured on two sides of the edge; the middle of the upper surface of the lead frame is fixed with an adapter plate, the upper surface and the lower surface of the adapter plate are distributed with wires, and a bonding pad at the edge area of the adapter plate is connected with a packaging pin through a wire; installing a chip on the upper surface of the adapter plate; and plastically packaging the whole structure formed by the lead frame structure, the adapter plate and the chip.)

1. A package structure, comprising:

the middle part of the lead frame structure is provided with a heat dissipation structure, and the edges of two sides of the lead frame structure are provided with packaging pins;

the adapter plate is fixed in the middle of the upper surface of the lead frame structure, the upper surface and the lower surface of the adapter plate are distributed with wiring, and a bonding pad at the edge area of the adapter plate is connected with the packaging pins through wires;

the chip is mounted on the upper surface of the adapter plate;

the outer sides of the lead frame structure, the adapter plate and the chip are wrapped by plastic package materials;

the chips are N chips, and N is a natural number.

2. The package structure of claim 1, wherein the heat dissipation structure is made of a metal material having conductive properties.

3. The package structure according to claim 1 or 2, wherein the interposer is fixed on the heat dissipation structure, the interposer includes a top wiring layer, an insulating layer, and a bottom wiring layer sequentially stacked from top to bottom, the top wiring layer has one or more layers of conductive traces and an insulating medium disposed between the conductive traces, and an upper surface of the top wiring layer is provided with a plurality of pads and/or bumps for mounting a chip and having conductivity; the bottom wiring layer is provided with one or more layers of conductive circuits and insulating media arranged among the conductive circuits; the insulating layer has a plurality of vias therein filled with a conductive material or a thermally conductive material to provide electrical or thermal communication between the top and bottom wiring layers.

4. The package structure of claim 3, wherein the interposer is a silicon interposer, a glass interposer, or an organic interposer.

5. The package structure of claim 3, wherein an underside of the bottom wiring layer is connected to the heat spreading structure through a thermally conductive material.

6. The package structure of claim 1, wherein the molding compound is an epoxy, a curing glue, or an EMC material.

7. A manufacturing method of a packaging structure comprises the following steps:

manufacturing a lead frame structure, and manufacturing packaging pins at the edges of two sides of the lead frame structure;

an adapter plate is fixed in the middle of the upper surface of the lead frame structure;

mounting a chip on the adapter plate, and connecting a bonding pad at the edge area of the adapter plate with a packaging pin through a lead;

and plastic packaging and cutting are carried out on the outer side of the whole structure consisting of the lead frame structure, the adapter plate and the chip.

8. The method of claim 5, wherein the chip is connected to the interposer using a positive lead attachment process.

9. The method of manufacturing of claim 5, wherein the chip is connected to the interposer using a flip-chip bonding process.

10. The method of claim 5, wherein the leadframe structure is formed by stamping or chemical etching.

Technical Field

The invention relates to the technical field of integrated circuit packaging, in particular to a high-density integrated packaging structure and a manufacturing method thereof.

Background

With the rapid development of the global market, the user demand for multifunctional, high-performance and high-integration electronic products is increasing, the demands are expanded from consumer products such as smart phones and flat panels to high-end products such as 5G communication, microwave radars and large data centers, and the development trend of the technology combining the moore's law and the ' post-moore ' law in recent years is combined, the development direction of the products in the future is high-density integration and volume miniaturization, the integration level and complexity of the products are increasing, and the power consumption and the cost are decreasing. In the post-Mole era, the improvement of product performance, the reduction of volume and the reduction of cost are realized, and the technical breakthrough of advanced packaging is relied on, so that higher requirements are correspondingly put forward on the advanced packaging high-density integration process.

The traditional integrated circuit packaging adopts a lead frame structure, the number of IO between systems is small, a high-density packaging structure cannot be realized, and the requirement of high-density integration of products is difficult to meet.

Disclosure of Invention

The present invention is directed to a package structure and a method for manufacturing the same, so as to solve the above-mentioned technical problems and achieve high-density integration of products.

In order to achieve the above-mentioned objects,

the invention provides a packaging structure suitable for high-density high-power, which comprises a lead frame structure, wherein the middle part of the lead frame structure is provided with a heat dissipation structure, and packaging pins are manufactured at the edges of two sides of the lead frame structure; the adapter plate is fixed in the middle of the upper surface of the lead frame structure, the upper surface and the lower surface of the adapter plate are distributed with wires, and a bonding pad at the edge area of the adapter plate is connected with the packaging pins through wires and used for signal interconnection; the chip is mounted on the upper surface of the adapter plate; the outer sides of the lead frame structure, the adapter plate and the chip are wrapped by plastic package materials; the chips are N chips, and N is a natural number.

In an embodiment of the present invention, the heat dissipation structure is made of a metal material having a conductive property.

In the embodiment of the invention, the adapter plate is fixed on the heat dissipation structure, the adapter plate comprises a top wiring layer, an insulating layer and a bottom wiring layer which are sequentially stacked from top to bottom, the top wiring layer is provided with one or more layers of conductive circuits and insulating media arranged among the conductive circuits, and the upper surface of the top wiring layer is provided with a plurality of conductive bonding pads and/or bumps for mounting a chip; the bottom wiring layer is provided with one or more layers of conductive circuits and insulating media arranged among the conductive circuits; the insulating layer has a plurality of vias therein filled with a conductive material or a thermally conductive material to provide electrical or thermal communication between the top and bottom wiring layers.

In an embodiment of the invention, the interposer is a silicon interposer, a glass interposer or an organic interposer.

In an embodiment of the invention, the lower side of the bottom wiring layer is connected to the heat dissipation structure by a thermally conductive material.

In an embodiment of the present invention, the plastic package material is epoxy resin, curing adhesive, or EMC material.

Another aspect of the present invention provides a method for manufacturing any one of the above package structures, the method comprising: manufacturing a lead frame structure, and manufacturing packaging pins at the edges of two sides of the lead frame structure; an adapter plate is fixed in the middle of the upper surface of the lead frame structure; mounting a chip on the adapter plate, and connecting a bonding pad at the edge area of the adapter plate with a packaging pin through a lead; and plastic packaging and cutting are carried out on the outer side of the whole structure consisting of the lead frame structure, the adapter plate and the chip.

In some embodiments of the present invention, the chip is connected to the interposer using a front-side-mount wire bonding process.

In some embodiments of the invention, the chip is connected to the interposer using a flip chip bonding process.

In some embodiments of the present invention, the lead frame structure is manufactured by a die stamping method, a chemical etching method, or the like.

The invention has the technical advantages that:

1) improving the overall wiring density: the invention adopts the adapter plate with TSV design, ensures high-density interconnection of chips, improves the overall wiring density and reduces the packaging volume.

2) Ensuring the high-frequency characteristic of the system: the chip signals are interconnected through the adapter plate, the signal connection is less, and the high-frequency characteristic damage of the system is avoided.

3) Enhancing heat dissipation performance: the invention adopts a back metal island packaging structure, and has better heat dissipation performance.

Drawings

Fig. 1 is a schematic cross-sectional view of a high-density high-power package structure according to an embodiment of the invention.

Fig. 2 is a flowchart of a manufacturing method of a high-density high-power package structure according to an embodiment of the invention.

Fig. 3A to fig. 3D are schematic cross-sectional views illustrating a manufacturing process of a high-density high-power package structure according to an embodiment of the invention.

Detailed Description

The invention provides a packaging structure suitable for high-density high-power and a manufacturing method thereof.

The technical solutions in the embodiments of the present invention are clearly and completely described below with reference to the drawings of the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. The specific embodiments described herein are merely illustrative of the invention and do not delimit the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Fig. 1 is a cross-sectional view of a package structure 100 suitable for high-density and high-power applications according to an embodiment of the invention. As shown in fig. 1, the package structure includes a lead frame structure 101, the lead frame structure 101 has a heat dissipation structure 102, and package leads 103 are formed on two sides of an edge of the lead frame structure 101. An adapter plate 104 is fixed in the middle of the upper surface of the lead frame 101, wires are distributed on the upper surface and the lower surface of the adapter plate 104, and a pad in the edge area of the adapter plate 104 is connected with the packaging pins 103 through wires and used for signal interconnection. The chip 105 is mounted on the upper surface of the interposer 104; the lead frame structure 101, the interposer 104, and the chip 105 form an integral structure, and the outer side of the integral structure is wrapped by a molding compound 107. The chip 105 may be a plurality of chips.

In the embodiment shown in fig. 1, the lead frame 101 is an interposer 104 and a chip 105 carrier, and the electrical connection of the circuit terminals of the interposer 104 and the external leads is realized by means of bonding materials (gold wire, aluminum wire, copper wire), forming an electrical circuit. The lead frame 101 may be formed by a die stamping method, a chemical etching method, or the like. The lead frame structure 101 may be made of copper alloy, iron-nickel alloy, etc., for example, the copper alloy is roughly classified into copper-iron system, copper-nickel-silicon system, copper-chromium system, copper-nickel-tin system (JK-2 alloy), etc., and the ternary, quaternary, etc. multicomponent copper alloy can achieve better performance than the traditional binary alloy, and has lower cost, and the copper-iron system has the most variety, better mechanical strength, stress relaxation resistance and low creep deformation, and is a good lead frame material. The material of the leadframe structure 101 may be selected based on the desired properties of the product, such as strength, electrical conductivity, and thermal conductivity.

In the embodiment shown in fig. 1, the heat dissipation structure 102 is made of a metal material with a good electrical conductivity, such as copper, aluminum, iron, etc., and can also function as a signal ground while improving the heat dissipation performance.

In the embodiment shown in fig. 1, the interposer 104 is designed with TSVs, which further increases the wiring density. The interposer 104 employs an interposer structure capable of high-density interconnection, such as a silicon interposer, a glass interposer, an organic interposer, and the like. The interposer 104 includes a top wiring layer, an insulating layer, and a bottom wiring layer sequentially stacked from top to bottom, the top wiring layer may have one or more layers of conductive traces and insulating medium disposed between the conductive traces, and the top surface of the top wiring layer is provided with a plurality of conductive pads and/or bumps for mounting a chip. The bottom wiring layer may have one or more layers of conductive traces and an insulating medium disposed between the conductive traces, and the underside of the bottom wiring layer may be connected to the heat dissipation structure 102 by a thermally conductive material. The insulating layer is made of silicon, glass or organic matter. The insulating layer has a plurality of vias therein that may be filled with a conductive material or a thermally conductive material to provide electrical or thermal communication between the top and bottom wiring layers.

In the embodiment shown in fig. 1, a plurality of chips with different functions can be mounted on the surface of the interposer 104 by flip-chip mounting, surface mounting (soldering or bonding) of BGA solder balls and wire bonding. Although fig. 1 illustrates the mounting of three chips, the scope of the present invention is not limited thereto. In other embodiments of the invention, more or fewer chips may be mounted on the surface of interposer 104. The material adopted by the BGA solder ball can be any one of tin-lead alloy, tin-lead-silver alloy, tin-silver-copper alloy, gold-germanium alloy and gold-tin alloy. The material, the components and the size of the BGA solder balls are selected correspondingly according to the assembly requirements of actual products.

In the embodiment shown in fig. 1, the one or more chips 105 may be logic operation chips such as a processor, DSP, FPGA, and AI chip, or may be dedicated chips such as a memory and a sensor.

In the embodiment shown in fig. 1, the material of the molding compound 107 may be epoxy resin, curing adhesive, EMC, or the like.

Fig. 2 shows a flow chart 200 of an embodiment of the invention for forming a package structure suitable for high density and high power. Fig. 3A to 3D are schematic cross-sectional views illustrating a process of forming a package structure suitable for high density and high power according to an embodiment of the present invention. The following describes a manufacturing process of a package structure suitable for high density and high power with reference to fig. 2 and fig. 3A to 3D.

It should be noted that, in order to distinguish the steps, the embodiments of the present invention describe the process steps in a specific order, which is not to limit the order of the steps, and in different embodiments of the present invention, the order of the steps may be adjusted according to the adjustment of the process.

First, in step 201, a lead frame structure 101 is fabricated. Package leads 103 are formed on two side edges of the lead frame, the middle portion of the lead frame is a heat dissipation structure 102, and in the embodiment shown in fig. 3A, the heat dissipation structure 102 is a metal island, however, the scope of the present invention is not limited thereto, and other types of heat dissipation structures may be selected according to actual requirements. The leadframe structure 101 may be formed by a die stamping process, a chemical etching process, or the like. The material of the leadframe structure 101 may be selected primarily based on the desired properties of the product, such as strength, electrical conductivity, and thermal conductivity.

At step 202, the interposer 104 is secured to a heat-dissipating structure on a leadframe. In the embodiment shown in fig. 3B, the interposer 104 is designed as a TSV, and the traces are distributed on the upper and lower surfaces.

At step 203, the chip 105 is mounted on the interposer 104 and wire interconnections with package pins are made at the interposer edge area. In the embodiment shown in fig. 3C, the chips 105 on both sides are bonded and mounted on the interposer 104 by an inverted stud bonding process, and the chip 105 in the middle is bonded by a positive lead bonding process, although the scope of the invention is not limited thereto, and other chip mounting processes may be used as desired. Pads at the edge of the interposer 104 are connected to the package pins 103 by leads 106.

And 204, carrying out plastic packaging and cutting to form a single package structure. In the embodiment shown in fig. 3D, the whole structure composed of the lead frame structure 101, the interposer 104, the chip 105 and the leads 106 is molded by using EMC material, however, the scope of the present invention is not limited thereto, and other materials may be molded according to actual requirements.

In the embodiment of the invention, the adapter plate adopting the TSV design ensures high-density interconnection of chips, improves the overall wiring density and reduces the packaging volume compared with the traditional integrated circuit packaging. Chip signals are interconnected through the adapter plate, and the high-frequency signals are effectively prevented from being damaged. The back metal island can also play a role in signal grounding while improving the heat dissipation performance.

While various embodiments of the present invention have been described above, it should be understood that they have been presented by way of example only, and not limitation. It will be apparent to persons skilled in the relevant art that various combinations, modifications, and changes can be made thereto without departing from the spirit and scope of the invention. Thus, the breadth and scope of the present invention disclosed herein should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents.