Shell packaging structure of IGBT module and method for detecting sealing performance of shell packaging structure

Abstract

The invention belongs to the technical field of IGBT module packaging, and relates to a shell packaging structure of an IGBT module and a method for detecting the sealing performance of the shell packaging structure. The packaging structure comprises a shell, a bottom plate is arranged below the shell, and the shell and the bottom plate are fixed through an adhesive glue; the outer side of a connecting area of the shell and the bottom plate is coated with a film layer. According to the detection method, the internal space pressure of the shell is pumped to negative pressure, and if a gap exists between the bottom plate and the shell, the film layer at the gap is burst through due to the pressure difference between the inside and the outside of the shell after a certain period of time. And then, the IGBT module is taken out of the equipment, whether air holes exist in the film layer coating the outer side of the connection area of the shell and the bottom plate or not is observed, a gap can be effectively prevented from existing between the shell and the bottom plate, the IGBT module with the air holes returns to a previous procedure to be reinstalled, and the IGBT module without the air holes normally circulates.

Description

technical field [0001] The invention belongs to the technical field of IGBT module encapsulation, and relates to the detection of the sealing performance of the IGBT module, in particular to a shell encapsulation structure of the IGBT module and a method for detecting its airtightness. Background technique [0002] At present, the shell mounting structure of the common soldered IGBT module is as follows: Figure 1-2 As shown, in order to realize the insulation, moisture-proof and buffering functions of the IGBT, the interior of the IGBT module is potted with silicone gel. During the silicone gel potting process, there is often a gap between the shell and the bottom plate, resulting in the silicone gel leaking from the gap, and then Lead to the scrapping of IGBT devices. However, at present, it is only possible to observe with the naked eye whether the glue leakage occurs after potting the silicone gel, and there is no effective means to prevent the occurrence of the above-me...

AI Technical Summary

Problems solved by technology

[0002] At present, the shell mounting structure of the common soldered IGBT module is as follows: Figure 1-2 As shown, in order to realize the insulation, moisture-proof and buffering functions of the IGBT, the interior of the IGBT module is potted with silicone gel. During the silicone gel potting process, there is often a gap between the shell and the bottom plate, resulting in the silicone gel leaking from the gap, and then Leading to the scrapping of IGBT devices

However, at present, it is only possible to observe with the naked eye whether the glue leakage occurs after potting the silicone gel, and there is no effective way to prevent the occurrence of the above problems.

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