Power Semiconductor Module Press-On Rail Assembly Against Warpage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Power semiconductor modules face challenges with heat dissipation due to warpage, which reduces efficiency and is not effectively addressed by existing designs that either compromise on flexibility or increase manufacturing complexity, and are not suitable for plastic encapsulated modules.
Innovation Solution
A power semiconductor module design featuring a housing and a separately manufactured press-on element with rail and limiting portions that allow for flexible and secure mounting to a heat sink element, preventing warpage and enabling efficient heat dissipation while being applicable to both glue-filled and plastic encapsulated modules.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If rigid contact with screws is used to fix the housing to the heat sink element, then the contact stability is improved, but the flexibility is reduced and aging occurs at stressed positions
Solution Approach 1:
The housing is divided into two independently manufacturable parts: the main housing body and the press-on element. The press-on element is separately manufactured and then assembled to the housing body through rail portions, allowing each part to be optimized independently for manufacturing while achieving the desired flexible yet stable contact with the heat sink element.
2Ease of operation
If press-on elements are embedded during injection molding, then flexible contact is achieved, but the manufacturing process becomes complicated and cost increases
Solution Approach 1:
Instead of embedding press-on elements during injection molding, the press-on element is manufactured separately as an independent component and then assembled to the housing body. This segmentation simplifies the injection molding process while maintaining the flexible contact capability through the separate assembly of the press-on element.
3Area of stationary object
If the power semiconductor module size is large, then heat dissipation contact area is increased, but warpage occurs at edge portions
Solution Approach 1:
The design changes the mechanical parameters of the contact interface by introducing rail portions with specific geometries (width, depth, spacing) that provide structural support to the housing body. These dimensional parameters are optimized to counteract warpage while maintaining adequate heat dissipation contact area.
4Reliability
If heat conductive silicone grease is used to fill gaps, then thermal connection is achieved, but excessive warpage reduces heat dissipation efficiency due to thicker grease layers
Solution Approach 1:
The rail portions are designed with specific dimensional parameters (width, depth, spacing) that mechanically support the housing body to minimize warpage. By controlling these geometric parameters, the gap between the heat-dissipation contact area and heat sink element is reduced, thereby minimizing the required thickness of heat conductive silicone grease and improving heat dissipation efficiency.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The design enhances heat dissipation efficiency, extends the module's service life, reduces production complexity, and allows for smaller size, easier packaging, and transportation, while maintaining stable contact between the heat-dissipation contact area and the heat sink element.
Implementation Method 1
heat conductive silicone grease at the bottom of the module directly contact with a heat sink element (comprising a cooling element) to dissipate heat generated by a semiconductor chip and the like in the power semiconductor module to the environment through the heat conductive silicone grease and the heat sink element
Data Source
Figure 1~2
Figure 3~4
Figure 5
AI summary
The present invention provides power semiconductor modules and their assembling methods. The power semiconductor module includes a heat-dissipation contact area, a housing and a press-on element. One of the housing and the press-on element includes a rail portion, while the other includes a rail cooperating portion. The housing and the press-on element respectively include a first limiting portion and a first limiting cooperating portion. The rail cooperating portion could be inserted into the rail portion and slides on the rail portion in the direction toward or away from the plane where the heat-dissipation contact area is located, so that the press-on element could move from the separation position to the mounted position connected with the housing. The rail portion could cooperate with the rail cooperating portion to prevent the press-on element from moving relative to the housing in the direction parallel to the plane where the heat-dissipation contact area is located. When the press-on element is located at the mounted position, the first limiting portion could cooperate with the first limiting cooperating portion to prevent the press-on element from moving relative to the housing in the direction toward the plane where the heat-dissipation contact area is located. The press-on element is configured for pressing the press-on element against the heat sink element in a state of being mounted on the heat sink element in the mounting position.