High-thermal-conductivity diamond IGBT heat dissipation structure

Abstract

The utility model provides a high thermal conductivity diamond IGBT heat radiation structure, comprising a diamond layer and an IGBT layer, one surface of the diamond layer is provided with a copper layer, at least one surface of the IGBT layer is provided with the diamond layer covered with the copper layer, and the IGBT layer is attached and connected with a part of the copper layer. According to the invention, by using the excellent thermal conductivity, insulativity and chemical inertness of the diamond, a novel IGBT packaging form is designed, and the heat dissipation performance of the IGBT is effectively improved; and the IGBT is directly electrically connected with the diamond layer and the copper layer, so that the heat dissipation efficiency of the IGBT is greatly improved. Compared with an existing ceramic substrate such as aluminum nitride and silicon nitride needing to add a bottom plate to be connected with a cooling device, the surface of the diamond is in direct contact with the cooling liquid, the interface thermal resistance is reduced, the heat dissipation efficiency is improved, and the heat dissipation efficiency is improved by more than 20% according to experimental results; and the IGBT can adopt more compact design during design, so that the final volume is reduced by more than 1 / 10 relative to the original volume.

Description

Technical Field

[0001] The utility model belongs to the technical field of semiconductors, and in particular relates to a high thermal conductivity diamond IGBT heat dissipation structure. Background Art

[0002] IGBT refers to insulated gate bipolar transistor, which is a composite fully controlled voltage-driven power semiconductor device composed of BJT (bipolar transistor) and MOS (insulated gate field effect transistor). It has the advantages of high input impedance of MOSFET and low conduction voltage drop of GTR. GTR has low saturation voltage drop and large current density, but large driving current; MOSFET has very small driving power and fast switching speed, but large conduction voltage drop and low current density. IGBT combines the advantages of the above two devices, with low driving power and low saturation voltage drop. It is very suitable for use in converter systems with DC voltage of 600V and above, such as AC motors, inverters, switching power supplies, lighting circuits, traction drives and other fields. IGBT modules have the characteristics of energy saving, easy installation and maintenance, and stable heat dissipation. As one of the important high-power mainstream devices of power electronics, IGBT has been widely used in household appliances, transportation, power engineering, renewable energy and smart grids. In industrial applications, such as traffic control, power conversion, industrial motors, uninterruptible power supplies, wind power and solar energy equipment, and inverters for automatic control; in consumer electronics, IGBT is used in home appliances, cameras and mobile phones; it has a wide range of applications.

[0003] The existing IGBT heat dissipation structure uses ceramic substrates such as aluminum nitride and silicon nitride. By adding copper layers on the upper and lower surfaces of the ceramic substrate and etching circuits, the IGBT is then welded to the ceramic substrate. The ceramic substrate and the copper layer on it provide electrical interconnection with the outside world and heat dissipation. However, due to the raw materials themselves, it cannot meet the higher heat dissipation requirements of the IGBT. Utility Model Content

[0004] The utility model provides a high thermal conductivity diamond IGBT heat dissipation structure, which can effectively solve the above problems.

[0005] The utility model is achieved in this way:

[0006] A high thermal conductivity diamond IGBT heat dissipation structure comprises a diamond layer and an IGBT layer, wherein a copper layer is arranged on one surface of the diamond layer, and at least one surface of the IGBT layer is arranged on a part of the copper layer of the diamond layer.

[0007] As a further improvement, diamond layers of the copper-clad layers are provided on opposite sides of the IGBT layer.

[0008] As a further improvement, a groove is provided on the surface of the diamond layer, the copper layer is filled in the groove, and the IGBT layer is bonded to the diamond layer and part of the copper layer.

[0009] As a further improvement, the groove extends to the side of the diamond layer, a copper layer is provided in the groove and on the side of the diamond layer corresponding to the groove, and the IGBT layer is bonded to the diamond layer and part of the copper layer.

[0010] As a further improvement, the surface of the diamond layer opposite to the IGBT layer is provided with a heat dissipation grid, a cooling pipe or a microchannel etched thereon.

[0011] As a further improvement, the cooling tube and the microchannel are connected with cooling liquid.

[0012] The beneficial effects of the utility model are as follows: the application utilizes the excellent thermal conductivity, insulation, and chemical inertness of diamond to design a new IGBT packaging form, which effectively improves the heat dissipation performance of the IGBT; the IGBT is directly electrically connected to the diamond layer and through the copper layer, which greatly improves the heat dissipation efficiency of the IGBT. Compared with the existing ceramic substrates such as aluminum nitride and silicon nitride, which need to add a bottom plate to connect with the cooling device, the diamond surface is directly in contact with the coolant, which reduces the interface thermal resistance and improves the heat dissipation efficiency. According to experimental results, the heat dissipation efficiency is improved by more than 20%; and the IGBT can be designed with a more compact design, so that the final volume is reduced by more than 1 / 10 compared with the original. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the technical solution of the implementation mode of the utility model, the drawings required for use in the implementation mode will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.

[0014] Figure 1 This is a schematic diagram provided by an embodiment of a high thermal conductivity diamond IGBT heat dissipation structure of the utility model;

[0015] Figure 2 This is a schematic diagram provided by an embodiment of a high thermal conductivity diamond IGBT heat dissipation structure of the utility model;

[0016] Figure 3 This is a top view of an embodiment of a high thermal conductivity diamond IGBT heat dissipation structure provided by the utility model;

[0017] Figure 4 This is a schematic diagram provided by an embodiment of a high thermal conductivity diamond IGBT heat dissipation structure of the utility model;

[0018] Figure 5 This is a schematic diagram provided by an embodiment of a high thermal conductivity diamond IGBT heat dissipation structure of the utility model;

[0019] Figure 6 This is a schematic diagram provided by an embodiment of a high thermal conductivity diamond IGBT heat dissipation structure of the utility model;

[0020] Figure 7 This is a schematic diagram provided by an embodiment of a high thermal conductivity diamond IGBT heat dissipation structure of the utility model;

[0021] Figure 8 This is a schematic diagram provided by an embodiment of a high thermal conductivity diamond IGBT heat dissipation structure of the utility model;

[0022] Fig. 9 This is a schematic diagram provided by an embodiment of a high thermal conductivity diamond IGBT heat dissipation structure of the utility model;

[0023] Fig.10 This is a schematic diagram provided by an embodiment of a high thermal conductivity diamond IGBT heat dissipation structure of the utility model;

[0024] Fig.11 It is a schematic diagram provided by an embodiment of a high thermal conductivity diamond IGBT heat dissipation structure of the utility model. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model. Therefore, the following detailed description of the embodiments of the utility model provided in the drawings is not intended to limit the scope of the utility model for which protection is claimed, but merely represents selected embodiments of the utility model.

[0026] In the description of the present invention, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0027] In the description of the present invention, the terms "upper", "middle", "side", "side", "upper side", "end" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0028] Reference Figure 1-11 As shown, a high thermal conductivity diamond IGBT heat dissipation structure includes a diamond layer and an IGBT layer, wherein a copper layer is disposed on one surface of the diamond layer, and at least one side of the IGBT layer is disposed with a diamond layer covered with a copper layer, and the IGBT layer is bonded and connected to a portion of the copper layer.

[0029] The copper layer is bonded to the surface of the diamond layer by electroplating or sputtering.

[0030] A copper layer about 300um thick is set on the surface of the diamond layer and the designed circuit is etched to provide a welding site for the IGBT and a channel for the IGBT to be electrically interconnected with the outside world.

[0031] The surface area of ​​the diamond layer is larger than that of the copper layer. The surface area of ​​the copper layer can be larger than that of the IGBT layer, so that the IGBT layer covers the surface of the copper layer, one end of the IGBT layer can be aligned with the copper layer, or the IGBT layer is arranged in the middle of the copper layer, so that a connection point is reserved at one end of the copper layer.

[0032] Furthermore, diamond layers are provided on opposite surfaces of the IGBT layer and the copper-clad layer.

[0033] The diamond layer with copper cladding is provided on the opposite sides of the IGBT layer to increase the heat dissipation effect.

[0034] Furthermore, a groove is provided on the surface of the diamond layer, the copper layer is filled in the groove, and the IGBT layer is bonded to the diamond layer and part of the copper layer.

[0035] By setting a groove on the surface of the diamond layer and setting a copper layer in the groove, a part of the IGBT layer is bonded to the diamond layer to achieve direct heat transfer between the IGBT layer and the diamond layer, thereby improving the heat dissipation effect; a part is connected to the copper layer to ensure electrical connection.

[0036] The surfaces of the diamond layer and the IGBT layer substrate (the substrate is Si, SiC, GaN, etc., and X is used to represent the IGBT substrate) are treated to form C-OH and X-OH, and are first contacted with each other under certain vacuum conditions. Then, they are annealed at about 300°C for about 25 hours to cause a dehydration reaction. At the same time, during the annealing process, the substrate is subjected to a bonding pressure of about 15MPa, and finally a COX covalent bond is formed to complete the bonding of the diamond and the IGBT.

[0037] Furthermore, the groove extends to the side of the diamond layer, a copper layer is provided in the groove and on the side of the diamond layer corresponding to the groove, and the IGBT layer is bonded to the diamond layer and part of the copper layer.

[0038] The groove extends to the side of the diamond layer, and the copper layer is extended to the side of the diamond layer. The electrical connection point can be realized on the side of the diamond layer, thereby reducing the overall area of ​​the diamond layer and saving costs.

[0039] Furthermore, a surface of the diamond layer opposite to the IGBT layer is provided with a heat dissipation grid, a cooling pipe or a microchannel etched thereon.

[0040] Furthermore, the cooling tube and the microchannel are connected with a cooling liquid.

[0041] Heat dissipation grilles or micro channels improve heat dissipation efficiency.

[0042] The above description is only the preferred implementation of the utility model, and is not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A high thermal conductivity diamond IGBT heat dissipation structure, characterized in that: It comprises a diamond layer and an IGBT layer, wherein a copper layer is disposed on one surface of the diamond layer, and at least one surface of the IGBT layer is provided with a diamond layer covered with a copper layer, and the IGBT layer is bonded and connected to a part of the copper layer.

2. A high thermal conductivity diamond IGBT heat dissipation structure according to claim 1, characterized in that: The diamond layer of the copper-clad layer is disposed on opposite surfaces of the IGBT layer.

3. A high thermal conductivity diamond IGBT heat dissipation structure according to claim 1 or 2, characterized in that: The surface of the diamond layer is provided with a groove, the copper layer is filled in the groove, and the IGBT layer is bonded to the diamond layer and part of the copper layer.

4. A high thermal conductivity diamond IGBT heat dissipation structure according to claim 3, characterized in that: The groove extends to the side of the diamond layer, and a copper layer is provided in the groove and on the side of the diamond layer corresponding to the groove.

5. A high thermal conductivity diamond IGBT heat dissipation structure according to claim 1, 2 or 4, characterized in that: The surface of the diamond layer opposite to the IGBT layer is provided with a heat dissipation grid, a cooling pipe or a micro-channel etched thereon.

6. A high thermal conductivity diamond IGBT heat dissipation structure according to claim 5, characterized in that: The cooling pipe and the microchannel are connected with cooling liquid.

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