CN-122008490-A - Self-adaptive lamination glue overflow-preventing semiconductor packaging mold and packaging process thereof

CN122008490ACN 122008490 ACN122008490 ACN 122008490ACN-122008490-A

Abstract

The invention discloses a self-adaptive lamination anti-overflow semiconductor packaging die and a packaging process thereof, wherein the die comprises a lower die cavity strip, an upper die cavity strip and a base thereof, wherein a floating radiator pressing block is arranged in the upper die cavity strip, an elastic reset mechanism is arranged between the pressing block and the base, the lower end surface of the pressing block protrudes out of the bottom surface of a die cavity in the initial stage of die opening and die closing, the elastic force automatically compensates and is tightly attached to a radiator on a frame, the glue overflow caused by the infiltration of molten resin into the surface of the radiator is prevented, and in the injection molding pressure maintaining stage, when the resin pressure in the die cavity reaches a preset threshold value, the upward thrust overcomes the elastic force to drive the pressing block to compress the elastic mechanism to retreat upwards, so that the mechanical stress accumulated in the frame during die closing is released. The invention realizes the self-adaption of the feeding tolerance of the frame through the physical process of floating lamination and dynamic release, effectively solves the problem of glue overflow caused by height difference fluctuation, and improves the long-term reliability of the packaged product.

Inventors

CAO SHENBIN
TONG HUA
Yi Tengha

Assignees

东和半导体设备(南通)有限公司

Dates

Publication Date: 20260512
Application Date: 20260414

Claims (5)

1. The self-adaptive lamination glue overflow-preventing semiconductor packaging die comprises a lower die cavity strip (1), an upper die cavity strip (3) and an upper die cavity strip base (4) and is characterized in that a floating radiator pressing block (5) is arranged in the upper die cavity strip (3), and an elastic reset mechanism (6) is arranged between the radiator pressing block (5) and the upper die cavity strip base (4); The elastic reset mechanism (6) is used for providing pretightening force at the initial stage of die opening and die closing, so that the lower end surface of the radiator pressing block (5) protrudes out of the bottom surface of the cavity of the upper die cavity strip (3) to compensate the height difference of the radiator; The radiator pressing block (5) is configured to be capable of retreating backwards against the elasticity of the elastic reset mechanism (6) to release the internal stress of the frame when the resin pressure in the cavity reaches a preset threshold value in the injection molding pressure maintaining stage.
2. The semiconductor packaging die capable of adaptively laminating and preventing glue overflow according to claim 1, wherein the elastic element (6) is one of a spring, a shrapnel, a magnetic mechanism or a pneumatic/hydraulic cylinder.
3. The self-adaptive lamination glue overflow-preventing semiconductor packaging die as claimed in claim 1, wherein a sealing structure is arranged between the radiator pressing block (5) and the inner wall of the upper die cavity strip (3) and is used for preventing resin from penetrating into the mounting area of the elastic reset mechanism (6).
4. A packaging process of a semiconductor packaging mold based on the self-adaptive lamination anti-overflow adhesive as claimed in any one of claims 1 to 3, which is characterized by comprising the following physical processes: the floating attaching process is to drive the lower end face of the radiator pressing block (5) to be tightly attached to the radiator surface of the frame (2) by utilizing the pretightening force of the elastic reset mechanism (6) when the die is assembled, and a gap is reserved between the bottom face of the cavity of the upper die cavity strip (3) and the terminal surface of the frame (2); And in the dynamic release process, when the upward thrust generated by the resin pressure built in the cavity is larger than the sum of the elastic force and the friction force of the elastic reset mechanism (6) during injection molding and pressure maintaining, the radiator pressing block (5) compresses the elastic reset mechanism (6) to retract upwards until the preset gap between the radiator pressing block (5) and the upper model cavity bar base (4) is eliminated, and at the moment, the frame (2) is restored to an unstressed state or a low-stress state.
5. The packaging process of the self-adaptive lamination glue overflow-preventing semiconductor packaging die according to claim 4, wherein the pretightening force fplay of the elastic reset mechanism (6) is as follows: In the mold closing stage, F is larger than the deformation force required by the pressing of the radiator so as to ensure sealing; in the pressure maintaining stage, F < pre > is smaller than the product of the maximum resin pressure Pmax and the stressed area S of the radiator, namely F Pre-preparation ＜ P max x S, so as to ensure that the pressing block can be pushed to retract by the resin pressure.

Description

Self-adaptive lamination glue overflow-preventing semiconductor packaging mold and packaging process thereof Technical Field The invention belongs to the technical field of semiconductor packaging, and particularly relates to a self-adaptive lamination glue overflow-preventing semiconductor packaging die and a packaging process thereof. Background In a conventional semiconductor packaging process, particularly for products such as IGBT modules, which require a radiator to be packaged and then exposed, a specific mold structure is generally used to achieve good isolation between the exposed surface of the radiator and the resin, and the structure includes a lower mold cavity bar and an upper mold cavity bar mounted on a base of the upper mold cavity bar. The process is to press the frame with the cooling fins through the upper die cavity, and then to package the frame with the cooling fins with resin. In order to ensure that the bottom of the upper mold cavity can be closely attached to the exposed surface of the radiator after mold closing, thereby effectively preventing resin flash, the key design is that the height difference between the exposed surface of the radiator and the terminal surface of the frame is larger than the depth of the cavity. However, due to the great difficulty in precision control in the manufacturing process, the height difference often fluctuates, and the situation that the height difference is smaller than the depth of the cavity easily occurs. When this condition takes place, will produce the clearance between radiator and the last model chamber bottom for unable laminating completely after the compound die, when carrying out the resin encapsulation, the resin very easily oozes the radiator along the clearance and exposes face, causes the surface to spill glues, and then leads to the product to scrap. Disclosure of Invention The invention aims to provide a self-adaptive lamination anti-overflow semiconductor packaging die and a packaging process thereof, so as to solve the problems in the background art. In order to achieve the aim, the invention provides the technical scheme that the self-adaptive lamination anti-overflow semiconductor packaging die comprises a lower model cavity strip, an upper model cavity strip and an upper model cavity strip base, wherein a floating radiator pressing block is arranged in the upper model cavity strip, and an elastic reset mechanism is arranged between the radiator pressing block and the upper model cavity strip base; the elastic reset mechanism is used for providing pretightening force at the initial stage of die opening and die closing, so that the lower end surface of the radiator pressing block protrudes out of the bottom surface of the cavity of the upper die cavity strip to compensate the height difference of the radiator; The radiator pressing block is configured to be capable of retreating backwards against the elasticity of the elastic reset mechanism to release the internal stress of the frame when the resin pressure in the cavity reaches a preset threshold value in the injection molding pressure maintaining stage. Preferably, the elastic element is one of a spring, a shrapnel, a magnetic mechanism or a pneumatic/hydraulic cylinder. Preferably, a sealing structure is arranged between the radiator pressing block and the inner wall of the upper model cavity strip and used for preventing resin from penetrating into the installation area of the elastic resetting mechanism, so that a physical barrier is constructed, and the penetration of molten resin into the installation area of the elastic element is effectively blocked. A packaging technology of a semiconductor packaging mould capable of adaptively laminating anti-overflow glue comprises the following physical processes: the floating attaching process is to drive the lower end face of the radiator pressing block to be tightly attached to the radiator surface of the frame by utilizing the pretightening force of the elastic reset mechanism when the die is assembled, and a gap is reserved between the bottom face of the cavity of the upper die cavity strip 3 and the terminal surface of the frame; and in the dynamic release process, when the upward pushing force generated by the resin pressure built in the cavity is larger than the sum of the elastic force and the friction force of the elastic reset mechanism during injection molding and pressure maintaining, the radiator pressing block compresses the elastic reset mechanism to retract upwards until the preset gap between the radiator pressing block and the upper model cavity bar base is eliminated, and the frame is restored to a stress-free state or a low-stress state. Preferably, the packaging process according to claim is characterized in that the pre-tightening force F of the elastic restoring mechanism is pre-satisfied: In the mold closing stage, F is larger than the deformation force required by the pressing of the radiator so as to