Stacked power module package

Abstract

The invention relates to a stacked power module package. The stacked power module package comprises a ceramic substrate; comprising an IGBT chip which is installed on the top surface of a ceramic substrate. Comprising an FRD chip which is inversely arranged on an IGBT chip, and the FRD chip and the IGBT chip are connected in parallel; comprising a concave island, the concave island is arranged on a ceramic substrate, and the concave island is in a hollow cylinder shape; comprising Pins, the Pins are inserted into the concave islands, the bottoms of the Pins are welded and fixed to the ceramic substrate, and the heat dissipation structure has the advantages that the heat dissipation area is increased, heat dissipation of the Pins is facilitated, welding looseness caused by heat accumulation at the welding position is avoided, and the connection stability and reliability are improved.

Description

Technical Field

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

[0002] The power module is a combination of power electronic devices according to certain functions and then encapsulated into a module. The power module includes a ceramic substrate (DBC for short), which is made by eutectic sintering of a ceramic substrate and copper foil at high temperature. The ceramic substrate is a three-layer structure with a ceramic insulating layer in the middle and copper cladding layers on the top and bottom. A pattern that can carry current is etched on the front, and the back must be directly welded to the heat dissipation substrate. Pins are also welded on the ceramic substrate.

[0003] However, since there is no gap between the ceramic substrate and the pin needle, and the welding area is small, the welding is prone to loosening, resulting in poor welding. In addition, the module will generate heat when working, and the heat will also accumulate at the welding point, causing the welding to loosen.

[0004] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0005] In view of the deficiencies of the prior art, the present invention discloses a stacked power module package.

[0006] The technical solution adopted by the present invention is as follows:

[0007] A stacked power module package includes a ceramic substrate; an IGBT chip, which is mounted on the top surface of the ceramic substrate; an FRD chip, which is flipped on the IGBT chip and connected in parallel; a concave island, which is arranged on the ceramic substrate and is arranged in a hollow cylindrical shape; and a Pin needle, which is inserted into the concave island and the bottom of the Pin needle is fixed to the ceramic substrate by welding.

[0008] Furthermore, the concave island includes at least two arc-shaped ribs, and the ribs form a concave island.

[0009] Furthermore, gaps are left between adjacent ribs.

[0010] Furthermore, the top and bottom of the rib plate are provided with an annular outer edge extending outward.

[0011] Furthermore, the diameter of the inner hole of the concave island is the same as the diameter of the Pin needle.

[0012] Furthermore, the top and bottom of the IGBT chip are coated with high-conductivity adhesive, the bottom of the IGBT chip is attached to the ceramic substrate through the high-conductivity adhesive, and the top of the IGBT chip is fixed to the FRD chip through the high-conductivity adhesive.

[0013] Furthermore, a shell is arranged outside the ceramic substrate, and the ceramic substrate is located in an internal space surrounded by the shell.

[0014] Furthermore, the side plate height of the housing is greater than the total stacked height of the ceramic substrate, the IGBT chip and the FRD chip.

[0015] Furthermore, a groove is provided at the outer edge of the bottom surface of the ceramic substrate, and the bottom plate of the shell is embedded in the groove.

[0016] The beneficial effects of the present invention are as follows:

[0017] 1. The IGBT chip and FRD chip are installed on the ceramic substrate in a stacked manner. Since the IGBT chip occupies a large area on the top of the copper foil of the ceramic substrate, the FRD chip is also indirectly dissipated through the IGBT chip, with better heat dissipation efficiency. The concave island is used to wrap the contact Pin needle to increase the contact area between the two, which is beneficial to the heat dissipation of the Pin needle, avoiding heat accumulation at the welding point causing loose welding, and improving the stability and reliability of the connection.

[0018] 2. The arc-shaped ribs fit the shape of the pins, constraining the posture of the pins to prevent the pins from shifting. The upper and lower ends of the ribs are provided with outer edges to increase the area, improve the heat dissipation effect, and greatly increase the welding area, making the welding more firm.

[0019] 3. The ceramic substrate and the bottom plate of the shell are connected by concave edges, which greatly increases the welding area and makes the welding and fixing of the two more firm. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A front view of a stacked power module package.

[0021] Figure 2 The figure is a schematic diagram of the structure of a stacked power module package.

[0022] Figure 3 A top view of the ceramic substrate.

[0023] Figure 4 for Figure 1 Schematic diagram of the local enlarged structure at point A in the middle.

[0024] Figure 5 A top view of a stacked power module package.

[0025] In the figure: 1. Ceramic substrate; 2. Shell; 3. IGBT chip; 31. High conductive adhesive; 4. FRD chip; 5. Concave island; 51. Rib; 6. Pin. DETAILED DESCRIPTION

[0026] The specific implementation of the present invention will be described below in conjunction with the accompanying drawings.

[0027] In order to make the purpose, technical scheme and advantages of the present invention clearer, the device proposed by the present invention is further described in detail below in conjunction 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 accompanying drawings adopt 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 purpose, 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 structure, proportion, size, etc. illustrated by the accompanying drawings of this specification are only used to match the content 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 modification of the structure, change of the proportional relationship or adjustment of the size, without affecting the effect that the present invention can produce and the purpose that can be achieved, should still fall within the scope of the technical content disclosed by the present invention.

[0028] Example:

[0029] A stacked power module package, such as Figure 1 As shown, Figure 1 The front view of a stacked power module package includes a ceramic substrate 1, an IGBT chip 3, an FRD chip 4, a concave island 5 and a pin 6. The IGBT chip 3, the concave island 5 and the pin 6 are mounted on the ceramic substrate 1, the FRD chip 4 is mounted on the IGBT chip 3, and the pin 6 is fixed in the concave island 5, forming a power module package.

[0030] Further, such as Figure 1 and Figure 2 As shown, Figure 2 It is a schematic diagram of the structure of a stacked power module package, in which a ceramic substrate 1 is connected to a housing 2, the side plate height of the housing 2 is greater than the total stacking height of the ceramic substrate 1, the IGBT chip 3 and the FRD chip 4, and the housing 2 protects the surroundings of the ceramic substrate 1, that is, the ceramic substrate 1 is located in the internal space surrounded by the housing 2. A groove is provided at the outer edge of the bottom surface of the ceramic substrate 1, and the bottom plate of the housing 2 is embedded in the groove to increase the welding contact area and improve the welding strength.

[0031] Further, such as Figure 2 and Figure 3 As shown, Figure 3is a top view of the ceramic substrate 1 . The top surface of the ceramic substrate 1 is divided into a plurality of regions according to design requirements, and the IGBT chips 3 are respectively mounted in various regions.

[0032] Further, such as Figure 2 and Figure 4 As shown, Figure 4 for Figure 1 In the enlarged structural diagram at A in the middle, the top and bottom of the IGBT chip 3 are coated with a high-conductivity glue 31. The top of the IGBT chip 3 is fixed to the FRD chip 4 through the high-conductivity glue 31, and the bottom of the IGBT chip 3 is fixed to the ceramic substrate 1 through the high-conductivity glue 31. And the FRD chip 4 is flipped on the IGBT chip 3, and the two are connected in parallel. When in use, the current direction of the IGBT chip 3 is from bottom to top, and the current direction of the FRD chip 4 is from bottom to top. The stacked chips used can increase the heat dissipation area of ​​the copper skin and accelerate heat dissipation.

[0033] Further, such as Figure 2 and Figure 5 Show, Figure 4 It is a top view of a stacked power module package. The concave island 5 includes at least two arc-shaped ribs 51. In this embodiment, the number of ribs 51 is set to three. The ribs 51 are evenly arranged along the circumferential direction to form a concave island 5. The inner diameter of the concave island 5 is the same as the diameter of the Pin needle 6. And there is a gap between adjacent ribs 51 to provide welding space for convenient welding. The top and bottom of the rib 51 are provided with an annular outer edge extending outward to increase the surface area of ​​the top and bottom of the rib 51. On the one hand, the contact area between the bottom surface of the Pin needle 6 and the ceramic substrate 1 is increased to increase the welding firmness. On the other hand, the heat dissipation area is increased through the rib 51 to improve the heat dissipation efficiency.

[0034] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0035] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A stacked power module package, characterized in that: including a ceramic substrate; It includes an IGBT chip, wherein the IGBT chip is mounted on the top surface of the ceramic substrate; It includes an FRD chip, wherein the FRD chip is flip-mounted on the IGBT chip, and the two are connected in parallel; It comprises a concave island, wherein the concave island is arranged on a ceramic substrate, and the concave island is arranged in a hollow cylindrical shape; The invention comprises a pin needle, wherein the pin needle is inserted into a concave island, and the bottom of the pin needle is fixed to a ceramic substrate by welding.

2. The stacked power module package according to claim 1, characterized in that: The concave isolated island comprises at least two arc-shaped ribs, and the ribs form a concave isolated island.

3. The stacked power module package according to claim 2, characterized in that: There are gaps between adjacent ribs.

4. The stacked power module package according to claim 2, characterized in that: The top and bottom of the rib plate are provided with an annular outer edge extending outward.

5. The stacked power module package according to claim 2, characterized in that: The diameter of the inner hole of the concave island is the same as the diameter of the Pin needle.

6. The stacked power module package according to claim 1, characterized in that: The top and bottom of the IGBT chip are coated with high-conductivity adhesive, the bottom of the IGBT chip is attached to the ceramic substrate through the high-conductivity adhesive, and the top of the IGBT chip is fixed to the FRD chip through the high-conductivity adhesive.

7. The stacked power module package according to claim 1, characterized in that: A shell is arranged outside the ceramic substrate, and the ceramic substrate is located in an internal space surrounded by the shell.

8. The stacked power module package according to claim 7, characterized in that: The side plate height of the housing is greater than the total stacking height of the ceramic substrate, the IGBT chip and the FRD chip.

9. The stacked power module package according to claim 7, characterized in that: The outer edge of the bottom surface of the ceramic substrate is provided with a groove, and the bottom plate of the shell is embedded in the groove.

Images