CN219108061U

CN219108061U - Synchronous heat radiation structure of printed circuit board and chip package

Info

Publication number: CN219108061U
Application number: CN202223147095.9U
Authority: CN
Inventors: 王双福; 滕天杰; 魏启甫
Original assignee: Hl Tronics Kunshan Co ltd
Current assignee: Hl Tronics Kunshan Co ltd
Priority date: 2022-11-26
Filing date: 2022-11-26
Publication date: 2023-05-30
Anticipated expiration: 2032-11-26

Abstract

The utility model discloses a synchronous heat dissipation structure for a printed circuit board and a chip package, which comprises a printed circuit board and a chip, wherein the chip is soldered above the printed circuit board through solder balls, a synchronous radiator is arranged above the printed circuit board, the synchronous radiator is covered on the chip and the printed circuit board, a first thermal interface material is arranged between the chip and the synchronous radiator, a second thermal interface material is arranged between the synchronous radiator and the printed circuit board, and the first thermal interface material and the second thermal interface material are one or more. The beneficial effects of the utility model are as follows: the synchronous heat dissipation of the chip package and the printed circuit board is realized, the effect of the whole heat dissipation capacity of the system is improved, and the technical problems that the traditional radiator has single heat dissipation path, cannot effectively dissipate heat of the printed circuit board and has lower heat dissipation efficiency are solved.

Description

Synchronous heat radiation structure of printed circuit board and chip package

Technical Field

The utility model relates to the field of heat dissipation of electronic systems and integrated circuits, in particular to a synchronous heat dissipation structure for a printed circuit board and a chip package.

Background

The integrated circuit industry has evolved most rapidly in recent decades, becoming one of the most emerging industries pushing society. With the increasing density of components, the operating speed and the scale of integrated circuits, the scale of integrated circuits is continuously expanding, and the size of integrated circuits is continuously advancing toward miniaturization.

With the continuous innovation of integrated circuit manufacturing technology, the transistor density of the chip is continuously improved, the chip area is continuously reduced, and meanwhile, the power consumption of the chip is higher and higher, and more heat is generated in unit time. This inevitably leads to an increase in the temperature of the component, and if not controlled, an excessively high temperature may affect the characteristics of the component while causing a decrease in the reliability thereof, and may eventually lead to failure of the component and cause malfunction of the apparatus. It is counted that 55% of the electronic device failures are caused by temperature. The related studies show that: the failure rate of the electronic component increases by 1 time when the working temperature of the electronic component increases by 10 ℃. The reliability problem caused by chip overheating mainly has three aspects: on the one hand, the materials of all parts of the component have different thermal expansion coefficients, the temperature rise can cause thermal stress to be generated, and structural damages such as interface stripping, warping, fracture and the like can be generated on the device structure, so that failure risks are generated; on the other hand, the junction temperature of the device is increased, the carrier mobility is reduced, electromigration, hot carrier effect and the like are generated, so that current is reduced, circuit delay is increased, circuit performance is affected, threshold voltage is reduced along with temperature rise, leakage current power consumption is increased by 10 times compared with that of room temperature when the temperature rises to 100 ℃, and the influence on the circuit is serious; on the other hand, too high a temperature accelerates material aging, so that the chip structure fails, and the service life of the device is influenced.

In this case, a very high requirement is placed on the heat dissipation capability of the device, and the power consumption of the integrated circuit directly causes the increase of the chip temperature, so that the thermal analysis of the integrated circuit has gradually become a hot spot in the analysis of the integrated circuit. Thermal effects must be considered in order to achieve the correct combination of power consumption, performance, reliability and packaging of the chip. The research on the packaging and heat dissipation of different chips is generally focused on aspects of packaging structures, packaging materials, radiators and the like, and only one of the research purposes is to reduce the thermal resistance on the heat transfer path of the chip and improve the heat dissipation capacity of the chip. The reduction of the thermal resistance can be divided into three parts, the first is an external heat dissipation means for reducing the thermal resistance packaged into the atmosphere; the second is a package heat dissipation means for reducing the thermal resistance of the package structure; the third is a heat dissipation means for chip internal heat conduction that reduces the internal thermal resistance of the chip. The way of reducing the internal thermal resistance of the chip and the thermal resistance of the packaging structure is limited by materials and design cost, and the thermal resistance which can be reduced is limited. The heat dissipation scheme of the packaged chip at present mainly adopts a method of adding an external heat radiator, and the main means is to add a heat dissipation device outside the packaged chip to reduce the thermal resistance of the packaged chip to the atmosphere.

The existing external heat dissipation mode is to install a heat sink on the surface of the packaged chip. As integrated circuit performance increases, the operating current increases and the operating voltage decreases, which results in a significant amount of heat power being dissipated through the conductors of the printed circuit board that they are being powered on, resulting in an increase in the temperature of the printed circuit board. For example, a high performance computing chip with an overall power consumption of 300W, which is typically under 1.0V, may have a supply current of 300A or more, and under such conditions, power consumption on a printed circuit board may be 30W or more. However, the existing active heat sinks or passive heat sinks only consider the heat dissipation requirement of the integrated circuit and ignore the heat power consumption on the printed circuit board, so that the heat dissipation performance of the system is limited.

The heat dissipation structure under the current technical conditions cannot simultaneously dissipate heat for the printed circuit board and the chip package, so that the heat dissipation efficiency is too low. There is no specific solution to the above problems.

Disclosure of Invention

The utility model aims to provide a synchronous heat dissipation structure for a printed circuit board and a chip package, which solves the problems in the background technology.

In order to achieve the above purpose, the present utility model provides the following technical solutions: the utility model provides a synchronous heat radiation structure of printed circuit board and chip encapsulation, includes printed circuit board and chip, the chip brazes in the printed circuit board top, the top of printed circuit board is equipped with synchronous radiator, synchronous radiator cover locates on chip and the printed circuit board, be equipped with first thermal interface material between chip and the synchronous radiator, be equipped with the second thermal interface material between synchronous radiator and the printed circuit board, first thermal interface material and second thermal interface material are one or more.

Further preferably, a first thermal contact surface and a second thermal contact surface are arranged below the synchronous radiator, and the synchronous radiator is in thermal contact with the first thermal interface material through the first thermal contact surface, so that effective heat conduction of the first thermal interface material is ensured, and good heat dissipation of the chip is further realized; the synchronous radiator is in thermal contact with the second thermal interface material through the second thermal contact surface, so that effective heat conduction of the second thermal interface material is ensured, and good heat dissipation of the printed circuit board is further realized.

Further preferably, the first thermal interface material and the second thermal interface material are both high heat conduction materials, so that efficient heat conduction is realized, and the heat conductivity is not lower than 2W/(m.K).

Further preferably, the upper surface and the side of the synchronous radiator are provided with radiating fins, so that the radiating area is increased, and the radiating effect is improved.

Further preferably, the side surface of the synchronous radiator is provided with a radiating hole, so that the air flow of the side surface of the chip is increased.

Further preferably, a cooling fan is arranged above or on the side of the synchronous radiator, so that the synchronous radiator is blown, the surface convection of the synchronous radiator is increased, and the cooling effect is improved.

Further preferably, the number of the chips is one or more, so that packaging of chips with different numbers is realized.

The beneficial effects are that: according to the synchronous heat dissipation structure for the printed circuit board and the chip package, the first thermal contact surface and the second thermal contact surface of the synchronous heat radiator are respectively in thermal contact with the first thermal interface material and the second thermal interface material, so that the synchronous heat radiator is in thermal connection with the printed circuit board and the chip, synchronous heat dissipation of the chip package and the printed circuit board is realized, good heat dissipation performance is realized, and the technical problem that the conventional heat radiator only dissipates heat of the chip package and cannot dissipate heat of the printed circuit board at the same time is solved.

Drawings

Fig. 1 is a schematic diagram of a synchronous heat dissipation structure of a printed circuit board and a chip package according to embodiment 1 of the present utility model;

fig. 2 is an exploded view of a synchronous heat dissipation structure for a printed circuit board and a chip package according to embodiment 1 of the present utility model;

fig. 3 is a schematic top view of a second thermal interface material and a second thermal contact surface of the synchronous heat dissipation structure for printed circuit board and chip package disclosed in embodiment 1 of the present utility model;

fig. 4 is a schematic diagram of a front view of a synchronous heat dissipation structure for a printed circuit board and a chip package according to embodiment 2 of the present utility model;

fig. 5 is an exploded view of a synchronous heat dissipation structure for a printed circuit board and a chip package according to embodiment 2 of the present utility model;

fig. 6 is a schematic top view of a second thermal interface material and a second thermal contact surface of the synchronous heat dissipation structure for printed circuit board and chip package disclosed in embodiment 2 of the present utility model;

fig. 7 is a schematic diagram of a side heat dissipation hole of a synchronous heat sink in a synchronous heat dissipation structure for a printed circuit board and a chip package according to embodiment 2 of the present utility model.

Reference numerals: 10-synchronous radiator, 101-first thermal contact face, 102-second thermal contact face, 1001-radiator fan, 1002-radiator fin, 20-first thermal interface material, 30-chip, 40-second thermal interface material, 50-printed circuit board.

Detailed Description

The following are specific embodiments of the present utility model and the technical solutions of the present utility model will be further described with reference to the accompanying drawings, but the present utility model is not limited to these embodiments.

Example 1

As shown in fig. 1-3, a synchronous heat dissipation structure for a printed circuit board and a chip package comprises a printed circuit board 50 and a chip 30, wherein the chip 30 is soldered above the printed circuit board 50 through solder balls, a synchronous heat radiator 10 is arranged above the printed circuit board 50, a containing cavity is arranged below the synchronous heat radiator 10 and is covered on the chip 30, heat dissipation and mechanical support can be realized through the synchronous heat radiator 10, the chip 30 is protected, efficient heat dissipation of the chip 30 is realized, and the influence on the package reliability of the chip 30 due to overlarge volume and weight of the synchronous heat radiator 10 is prevented. The number of the chips 30 can be one or more, and the packaging forms of the chips 30 can be various, and the chips can be packaged in various forms such as BGA, QFP or DIP. The first thermal interface material 20 is arranged between the chip 30 and the synchronous radiator 10, the good connection effect of the synchronous radiator 10 and the chip 30 can be realized through the first thermal interface material 20, the good heat conduction effect between the chip 30 and the synchronous radiator 10 is ensured, the first thermal interface material 20 is made of a high heat conduction material, and can be silicone grease, heat conduction silicone rubber, phase change heat conduction material, heat conduction adhesive film and the like, the high heat conduction capability is realized, and the good heat conduction and filling effects can be realized. By the arrangement of the first thermal interface material 20, the problem that the reliability of the chip 30 is reduced due to the fact that the synchronous radiator 10 and the chip are connected in the prior art by means of buckling by connecting glue or a metal heat conducting plate is solved. The second thermal interface material 40 is arranged between the synchronous radiator 10 and the printed circuit board 50, the full wrapping effect of the synchronous radiator 10 and the printed circuit board 50 on the chip 30 is achieved through the second thermal interface material 40, the packaging and the protection of the chip 30 are achieved, the second thermal interface material 40 is made of high-connection heat conducting materials, the connection effect is good, the connection stability of the synchronous radiator 10 can be enhanced, the good heat dissipation performance is achieved, the heat dissipation effect can be achieved on the printed circuit board 50, and the heat dissipation effect is improved.

Wherein, the first thermal interface material 20 and the second thermal interface material 40 are one or more, by adjusting the number of the first thermal interface material 20 and the second thermal interface material 40, the sum of the thickness of the one or more second thermal interface materials 40 and the height of the accommodating cavity of the synchronous heat spreader 10 can be equal to the sum of the thickness of the one or more first thermal interface materials 20 and the thickness of the chip 30, so as to ensure the structural supporting effect of the synchronous heat spreader 10 and the protection effect on the chip 30, and the synchronous heat spreader 10 will not crush the chip 30.

In this application, the below of synchronous radiator 10 is equipped with first thermal contact face 101 and second thermal contact face 102, and synchronous radiator 10 is through first thermal contact face 101 and first thermal interface material 20 thermal contact, realizes the close connection of synchronous radiator 10 and first thermal interface material 20, has good heat conduction effect, can give synchronous radiator 10 with the heat on the first thermal interface material 20 fast, realizes the quick heat dissipation to chip 30. The second thermal contact surface 102 surrounds the accommodation under the synchronous radiator 10, the cross section shape of the second thermal interface material 40 is the same as that of the second thermal contact surface 102, the synchronous radiator 10 is in thermal contact with the second thermal interface material 40 through the second thermal contact surface 102, the tight connection between the synchronous radiator 10 and the second thermal interface material 40 is achieved, a good heat conduction effect is achieved, heat on the second thermal interface material 40 can be quickly transferred to the synchronous radiator 10, and quick heat dissipation of the printed circuit board 50 is achieved.

In the application, the synchronous radiator 10, the first thermal interface material 20 and the chip 30 are mechanically connected, so that the synchronous radiator 10 and the chip 30 are firmly connected, displacement of the first thermal interface material 20 can be prevented, heat transfer of the chip 30 is affected, and the chip 30 can effectively dissipate heat; the synchronous radiator 10, the second thermal interface material 40 and the printed circuit board 50 are mechanically connected, so that the connection effect of the synchronous radiator 10 and the printed circuit board 50 is ensured, the stable supporting effect of the synchronous radiator 10 is realized, the chip 30 is strongly protected, and the heat dissipation effect of the printed circuit board 50 is ensured.

In this application, the upper surface and the side of synchronous radiator 10 all are equipped with fin 1002, increase synchronous radiator 10's heat radiating area, improve the radiating effect, can guarantee the effective heat dissipation of chip 30.

Example 2

As shown in fig. 4 to 7, in the present application, unlike in embodiment 1, a heat radiation fan 1001 is provided above or at the side of the synchronous heat sink 10, and the surface convection of the synchronous heat sink 10 is increased by blowing air through the heat radiation fan 1001, thereby improving the heat radiation effect; the heat radiation fan 1001 is disposed above or beside the synchronous radiator 10 to radiate heat. The flexibility of installation of the heat radiation fan 1001 is improved.

In this application, the printed circuit board 50 and the synchronous radiator 10 may have a semi-open package structure or a fully-closed package structure to the chip 30, and according to the structural design of the connection surface between the printed circuit board 50 and the second thermal interface material 40, the connection surface between the printed circuit board 50 and the second thermal interface material 40 may have two symmetrical contact surfaces, i.e. a semi-open package structure, or may have a closed loop-shaped contact surface, i.e. a closed package structure, as shown in fig. 5-6. When the printed circuit board 50 and the synchronous radiator 10 are of a closed package structure to the chip 30, the synchronous radiator 10 is provided with a radiating hole at a side surface so that the accommodating cavity and the outside are penetrated, as shown in fig. 7.

Finally, it should be noted that: the foregoing description is only a preferred embodiment of the present utility model, and the present utility model is not limited thereto, but it is to be understood that modifications and equivalents of some of the technical features described in the foregoing embodiments may be made by those skilled in the art, although the present utility model has been described in detail with reference to the foregoing embodiments. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model should be included in the summary of the present utility model within the scope of the present utility model.

Claims

1. The utility model provides a synchronous heat radiation structure of printed circuit board and chip package, includes printed circuit board (50) and chip (30), chip (30) braze in printed circuit board (50) top, its characterized in that: the synchronous radiator (10) is arranged above the printed circuit board (50), the synchronous radiator (10) is covered on the chip (30) and the printed circuit board (50), a first thermal interface material (20) is arranged between the chip (30) and the synchronous radiator (10), a second thermal interface material (40) is arranged between the synchronous radiator (10) and the printed circuit board (50), and the first thermal interface material (20) and the second thermal interface material (40) are one or more.

2. The synchronous heat dissipation structure of a printed circuit board and a chip package of claim 1, wherein: a first thermal contact surface (101) and a second thermal contact surface (102) are arranged below the synchronous radiator (10), the synchronous radiator (10) is in thermal contact with the first thermal interface material (20) through the first thermal contact surface (101), and the synchronous radiator (10) is in thermal contact with the second thermal interface material (40) through the second thermal contact surface (102).

3. The synchronous heat dissipation structure of a printed circuit board and a chip package of claim 1, wherein: the first thermal interface material (20) and the second thermal interface material (40) are both high thermal conductivity materials, and the thermal conductivity is not lower than 2W/(m.K).

4. The synchronous heat dissipation structure of a printed circuit board and a chip package of claim 1, wherein: the upper surface and the side surfaces of the synchronous radiator (10) are provided with radiating fins (1002).

5. The synchronous heat dissipation structure of a printed circuit board and a chip package of claim 1, wherein: and the side surface of the synchronous radiator (10) is provided with a radiating hole.

6. The synchronous heat dissipation structure of a printed circuit board and a chip package of claim 1, wherein: and a cooling fan (1001) is arranged above or on the side edge of the synchronous radiator (10).

7. The synchronous heat dissipation structure of a printed circuit board and a chip package of claim 1, wherein: the number of the chips (30) is one or more.