Semiconductor module and packaging structure

Abstract

The utility model relates to the semiconductor technology, and discloses a semiconductor module and a packaging structure, the semiconductor module comprises at least one group of semiconductor units, each semiconductor unit comprises a power unit and at least one heat dissipation unit, and the power units are connected with the heat dissipation units; the structure is characterized in that a copper nano-wire grows on the copper-clad surface of the power unit or the surface of the radiator; when the nanometer copper wire grows on one surface of the copper-clad surface of the power unit, the surface of the power unit, on which the nanometer copper wire grows, is connected with the heat dissipation unit. When the copper nano-wires grow on the two surfaces of the copper-clad surface of the power unit, the two surfaces, on which the copper nano-wires grow, of the power unit are connected with the heat dissipation unit. According to the semiconductor module designed by the utility model, the process temperature of connection between the module and the heat dissipation unit is reduced under the condition that noble metal silver is not used, high-efficiency and high-reliability connection between the power unit and the heat dissipation unit can be realized, extremely low thermal interface thermal resistance is obtained, and high-temperature damage to a shell of the power unit is avoided in the process.

Description

Technical Field

[0001] The utility model relates to semiconductor technology, in particular to a semiconductor module and a packaging structure. Background Art

[0002] With the development of third-generation semiconductors, the power density of power modules continues to increase, and the maximum junction temperature that chips can withstand is also increasing. Compared with the shell-mounted potting modules of the silicone system, the transfer mold plastic-sealed modules are more adaptable to the high junction temperature application conditions of the third-generation semiconductors. The most widely used plastic-sealed modules at present are the packaging forms of single-sided heat dissipation without direct water cooling PIN-FIN, such as Tesla's TPAK. This single-sided heat dissipation module needs to use press-fitting, welding, silver sintering or copper sintering and other technologies to achieve physical connection with the external heat sink in order to dissipate heat normally. The thermal interface material (TIM) connecting the module and the heat sink has always been one of the challenges of the semiconductor industry, that is, to continuously improve the heat dissipation efficiency while ensuring the normal operation and reliability of the module. To this end, the industry has been exploring TIMs with higher thermal conductivity, including high thermal conductivity silicone grease, high thermal conductivity and high reliability brazing technology and materials, sintered silver paste and silver film, sintered copper, etc.

[0003] For example, prior art 1, CN201010002698.2 relies on bolt tightening and press-fitting. Because the contact surface between the module and the radiator has flatness and roughness problems, there will be a gap at the contact boundary between the two at the microscopic level, so thermal conductive silicone grease is needed to fill it to reduce the contact thermal resistance as much as possible. However, the thermal conductivity of thermal conductive silicone grease is generally very poor, so it needs to be as thin as possible. However, silicone grease is liquid, and silicone grease may be lost during the service of the module due to the pumping effect caused by thermal expansion and contraction, which will aggravate its aging and drying.

[0004] Prior art 2, CN201210290297.0, requires high temperature. During the process of soldering the module to the radiator, the solder inside the module may also remelt or affect the IMC distribution of the solder inside the module, thereby affecting the reliability of the internal solder layer. At the same time, the module shell is plastic, and the temperature of brazing is generally much higher than the glass transition temperature of plastic, which may cause irreversible damage to the module. At the same time, the thermal conductivity of the solder is relatively low, and the solder layer is thick and has a large thermal resistance. The CTE mismatch between the solder and other materials also makes the connection interface prone to reliability problems.

[0005] Silver sintering is a precious metal with high thermal conductivity, but it is relatively expensive. It is active and easily oxidized. Other auxiliary materials need to be added to pre-make silver film or silver paste. The process is cumbersome and has strict requirements on the process environment. The process temperature and pressure need to be controlled, and there is an additional drying process. In addition, the module also needs to face reliability issues caused by silver migration during service.

[0006] Copper sintering, copper has high strength, and the sintering conditions are more stringent than silver sintering. The current process is immature, the porosity is high, the process temperature and process pressure are relatively high, and the energy consumption is high. Excessive temperature and process pressure may cause additional damage to the module. Summary of the invention

[0007] The utility model aims at the problems of complex process conditions and procedures, high energy consumption and low efficiency in the connection mode between the power unit and the heat dissipation unit in the prior art, and proposes a semiconductor module and a packaging structure.

[0008] In order to solve the above technical problems, the utility model is solved by the following technical solutions:

[0009] A semiconductor module comprises at least one group of semiconductor units, wherein the semiconductor units comprise a power unit and at least one heat dissipation unit, wherein the power unit is connected to the heat dissipation unit; nano-copper wires are grown on the copper-clad surface of the power unit; when nano-copper wires are grown on one side of the copper-clad surface of the power unit, the side of the power unit on which the nano-copper wires are grown is connected to the heat dissipation unit; when nano-copper wires are grown on both sides of the copper-clad surface of the power unit, both sides of the power unit on which the nano-copper wires are grown are connected to the heat dissipation unit.

[0010] Preferably, nano-copper wires are grown on the copper-clad surface of the heat dissipation unit; nano-copper wires are grown on one side of the copper-clad surface of the power unit, and the side of the power unit with the nano-copper wires grown is connected to the side of the heat dissipation unit with the nano-wires grown.

[0011] Preferably, nano copper wires are grown on both sides of the copper-clad surface of the power unit, and both sides of the power unit with nano copper wires grown are connected to one side of the heat dissipation unit with nano wires grown.

[0012] Preferably, the thickness of the nano copper wire is 5 nm to 500 nm, and the length of the nano copper wire is 10 μm to 100 μm.

[0013] In order to solve the above technical problems, the present application also provides a semiconductor module, including at least one group of semiconductor units, the semiconductor unit includes a power unit and at least one heat dissipation unit, the power unit is connected to the heat dissipation unit; the copper-clad surface of the heat dissipation unit is grown with nano-copper wires; the side of the heat dissipation unit where the nano-copper wires are grown is connected to the power unit.

[0014] Preferably, nano-copper wires are grown on the copper-clad surface of the power unit; when nano-copper wires are grown on one side of the copper-clad surface of the power unit, the side of the power unit on which the nano-copper wires are grown is connected to the side of the heat dissipation unit on which the nano-copper wires are grown; when nano-copper wires are grown on both sides of the copper-clad surface of the power unit, both sides of the power unit on which the nano-copper wires are grown are connected to the surface of the heat dissipation unit on which the nano-copper wires are grown.

[0015] Preferably, the thickness of the nano copper wire is 5 nm to 500 nm, and the length of the nano copper wire is 10 μm to 100 μm.

[0016] In order to solve the above technical problems, the present application also provides a packaging structure, which includes the semiconductor module.

[0017] The utility model adopts the above technical solution design:

[0018] The semiconductor module designed by the utility model does not require the use of precious metals, and the material cost is low;

[0019] The semiconductor module designed by the utility model does not require the introduction of additional auxiliary materials and process technologies, and the process is simple, efficient and low in energy consumption;

[0020] The semiconductor module designed by the utility model has low process temperature and process pressure, and will not cause additional damage to the module;

[0021] The semiconductor module connection interface designed by the utility model is homogeneous metal, there is no CTE mismatch problem, the reliability is high, and the sintered layer has high thermal conductivity, thin thickness and low thermal resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Structural diagram of embodiment 3 of the utility model;

[0023] Figure 2 Structural diagram of embodiment 5 of the utility model;

[0024] Figure 3 This is a structural diagram of Embodiment 1 of the utility model;

[0025] Figure 4 This is a structural diagram of Embodiment 2 of the present utility model;

[0026] Figure 5 It is a structural diagram of embodiment 10 of the present utility model. DETAILED DESCRIPTION

[0027] The utility model is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0028] Example 1

[0029] A semiconductor module, Figure 3 The invention comprises at least one group of semiconductor units, wherein the semiconductor units include a power unit and a heat dissipation unit, wherein the power unit is connected to the heat dissipation unit; wherein the copper-clad surface of the power unit is grown with nano-copper wires; wherein the copper-clad surface of the power unit is grown with nano-copper wires, and the surface of the power unit with the nano-copper wires is connected to the heat dissipation unit;

[0030] Nano copper wires of a certain thickness are grown on the surfaces of the power unit and the heat dissipation unit respectively. The surfaces of the power unit and the heat dissipation unit are generally made of metallic copper. If they are made of other materials, copper plating is required on the surface.

[0031] The power unit and the heat sink are connected together by pressing. The pressing process can be carried out at room temperature. In order to improve the pressing efficiency and enhance the interface bonding strength, a relatively mild process temperature can be additionally applied, such as 150-200°C. If the temperature resistance of the power module plastic packaging material is relatively high, the process temperature can be increased to 200-300°C.

[0032] Example 2

[0033] Based on Example 1, Figure 4 In this embodiment, the difference from the first embodiment is that nano copper wires are grown on both sides of the copper-clad surface of the power unit, and both sides of the power unit with nano copper wires grown are connected to the heat dissipation unit.

[0034] Example 3

[0035] Based on Example 1, Figure 1 In this embodiment, nano copper wires are grown on the copper-clad surface of the heat dissipation unit; nano copper wires are grown on one side of the copper-clad surface of the power unit, and the side of the power unit with the nano copper wires grown is connected to the side of the heat dissipation unit with the nano wires grown.

[0036] Example 4

[0037] Based on the third embodiment, nano copper wires are grown on both sides of the copper-clad surface of the power unit in this embodiment, and both sides of the power unit with nano copper wires grown are connected to one side of the heat dissipation unit with nano wires grown.

[0038] Example 5

[0039] A semiconductor module, Figure 5 The invention comprises at least one group of semiconductor units, wherein the semiconductor units include a power unit and a heat dissipation unit, wherein the power unit is connected to the heat dissipation unit; the copper-clad surface of the heat dissipation unit is grown with nano-copper wires; and the side of the heat dissipation unit where the nano-copper wires are grown is connected to the power unit. The non-connected area of ​​the copper-clad surface of the heat dissipation unit generally does not grow nano-copper wires, and the growth of nano-copper wires can be blocked by plating, wherein the plating includes but is not limited to nickel plating, tin plating, silver plating or gold plating.

[0040] Example 6

[0041] Based on Example 5, this embodiment is provided with two heat dissipation units, and nano-copper wires are grown on the copper-clad surfaces of the heat dissipation units; one of the heat dissipation units has one side on which the nano-copper wires are grown connected to the power unit; and the other heat dissipation unit has one side on which the nano-copper wires are grown connected to the other side of the power unit.

[0042] Example 7

[0043] On the basis of the above-mentioned embodiment, the diameter of the nano copper wire in this embodiment is 5 nm to 500 nm, and the thickness of the nano copper wire is 40 to 50 μm.

[0044] Example 8

[0045] Based on the above embodiment, the difference from embodiment 7 is that the diameter of the nano copper wire in this embodiment is 5 nm to 500 nm, and the thickness of the nano copper wire is 20 to 30 μm.

[0046] Example 9

[0047] Based on the above embodiment, the diameter of the nano copper wire in this embodiment is 5 nm to 500 nm, and the thickness of the nano copper wire is 10 to 20 μm.

[0048] Example 10

[0049] Based on the above embodiments, Figure 5 This embodiment is a packaging structure, which includes three semiconductor modules.

Claims

1. A semiconductor module, comprising at least one group of semiconductor units, wherein the semiconductor units include a power unit and at least one heat dissipation unit, wherein the power unit is connected to the heat dissipation unit; characterized in that: Nano-copper wires are grown on the copper-clad surface of the power unit or the surface of the heat dissipation unit; when nano-copper wires are grown on one side of the copper-clad surface of the power unit, the side of the power unit on which the nano-copper wires are grown is connected to the heat dissipation unit; when nano-copper wires are grown on both sides of the copper-clad surface of the power unit, both sides of the power unit on which the nano-copper wires are grown are connected to the heat dissipation unit.

2. A semiconductor module according to claim 1, characterized in that: Nano copper wires are grown on the copper-clad surface of the heat dissipation unit; nano copper wires are grown on one side of the copper-clad surface of the power unit, and the side of the power unit where the nano copper wires are grown is connected to the side of the heat dissipation unit where the nano wires are grown.

3. A semiconductor module according to claim 2, characterized in that: Nano copper wires are grown on both sides of the copper-clad surface of the power unit, and both sides of the power unit with the nano copper wires grown are connected to one side of the heat dissipation unit with the nano wires grown.

4. The semiconductor module according to claim 1, characterized in that: The diameter of the nano copper wire is 5nm to 500nm, and the length is 10μm to 100μm.

5. A semiconductor module, comprising at least one group of semiconductor units, wherein the semiconductor units include a power unit and at least one heat dissipation unit, wherein the power unit is connected to the heat dissipation unit; characterized in that: Nano copper wires are grown on the copper-clad surface of the heat dissipation unit; and one side of the heat dissipation unit on which the nano copper wires are grown is connected to the power unit.

6. A semiconductor module according to claim 5, characterized in that: Nano-copper wires are grown on the copper-clad surface of the power unit; when nano-copper wires are grown on one side of the copper-clad surface of the power unit, the side of the power unit on which the nano-copper wires are grown is connected to the side of the heat dissipation unit on which the nano-copper wires are grown; when nano-copper wires are grown on both sides of the copper-clad surface of the power unit, both sides of the power unit on which the nano-copper wires are grown are connected to the surface of the heat dissipation unit on which the nano-copper wires are grown.

7. The semiconductor module according to claim 5, characterized in that: The diameter of the nano copper wire is 5nm to 500nm, and the length is 10μm to 100μm.

8. A packaging structure, characterized in that: Comprising the semiconductor module according to any one of claims 1-7.

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