Injection molding method for plastic encapsulated type IPM and plastic encapsulated type IPM

Abstract

The invention discloses an injection molding method for a plastic encapsulated type IPM and the plastic encapsulated type IPM. The injection molding method comprises the following steps that firstly, the upper surface of a DBC substrate and the pin portion of lead frames are soldered and fixed together, a PCB and pins of the lead frames are soldered and fixed together, and assembly of the DBC substrate, the PCB and the lead frames is completed; secondly, the soldered lead frames are placed in an injection mold; thirdly, an upper mold body and a lower mold body of the injection mold are controlled to be assembled, an acting force is exerted on the upper surface of the DBC substrate through a plurality of elastic ejector pins, the elastic ejector pins are gradually compressed, and therefore the DBC substrate is tightly pressed; and fourthly, injection molding materials are injected into an injection molding area, and the copper layer on the back portion of the DBC substrate is made to be fully exposed. By the adoption of the injection molding method for the plastic encapsulated type IPM, the problem that materials overflow on the periphery of the copper layer of the DBC substrate after injection molding of the product can be effectively solved, it is guaranteed that the copper layer on the back face of the DBC substrate can be fully exposed outside the plastic encapsulating body after injection molding, and therefore the heat dissipating effect and the reliability of the product are improved.

Description

technical field [0001] The invention relates to the technical field of IPM injection molding, in particular to an injection molding fixing method for a DBC board in a plastic-encapsulated IPM, and a corresponding plastic-encapsulated IPM. Background technique [0002] Plastic-encapsulated IPM (Intelligent Power Module, Intelligent Power Module) is a new type of control module that integrates the IGBT chip and its drive circuit, control circuit and overcurrent, undervoltage, short circuit, overheating and other protection circuits. It is a complex and advanced power module that can automatically realize complex protection functions such as overcurrent, undervoltage, short circuit and overheating, so it has intelligent features. At the same time, it has the advantages of low cost, miniaturization, high reliability, and easy use. It is widely used in frequency conversion home appliances, inverter power supplies, industrial control and other fields, and its social and economic b...

AI Technical Summary

Problems solved by technology

[0006] (1) If the lead frame is deformed before injection molding, it will seriously affect its fixation to the DBC board, and then affect the injection molding result of the product, so that the injection plastic covers the copper layer on the bottom surface of the DBC;

[0007] (2) When the injection plastic body covered on the DBC board overflows, it will seriously affect the heat dissipation of the product;

[0008] (3) Too much flash requires laser deburring to remove the flash on the surface of the DBC copper layer, which will affect the efficiency of the entire production

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