Power Semiconductor Module Adhesive Tapered Portion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional semiconductor devices using high viscosity adhesives for sealing often experience reduced fluidity and air bubble generation, leading to insufficient insulation due to the adhesive's high viscosity and the resulting air bubbles, which can compromise the insulating properties between the resin-insulated base plate and the case.
Innovation Solution
A power semiconductor module design that incorporates a tapered portion on the case filled with adhesive, which is identical to the sealing resin, to prevent air bubbles from contacting the resin insulating layer, ensuring secure bonding and insulation by allowing air bubbles to float and remain in the tapered area, thus maintaining creepage distance and insulating properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If high viscosity adhesive is used to seal the case, then bonding strength is improved, but air bubbles are easily generated and fluidity decreases
Solution Approach 1:
The adhesive application area is segmented into two distinct zones: a tapered portion for air bubble accommodation and a flat portion for primary bonding. This segmentation allows the high viscosity adhesive to maintain bonding strength while providing a dedicated space for air bubbles to float without compromising insulation
Solution Approach 2:
The tapered portion acts as an intermediary zone between the adhesive and the resin insulating layer. It serves as a buffer that captures air bubbles generated during adhesive application, preventing them from reaching the critical insulation interface between the resin insulating layer and the case
2Strength
If high viscosity adhesive is used, then bonding strength is improved, but air bubbles are generated that compromise insulation
Solution Approach 1:
The invention converts the harmful effect of air bubble generation into a beneficial outcome by designing the tapered portion that actively directs air bubbles away from the insulation interface. The air bubbles, which would normally compromise insulation, are now contained in a designated zone where they cannot affect the electrical insulation between the resin insulating layer and the case
3Strength
If adhesive is applied to fill the space between case and base plate, then bonding is improved, but air bubbles reduce insulation quality
Solution Approach 1:
The bonding interface is segmented into a tapered portion for air bubble accommodation and a flat portion for maintaining precise insulation gaps. This segmentation allows the adhesive to provide bonding strength while the tapered geometry ensures air bubbles are directed away from the critical insulation interface, preserving manufacturing precision
Solution Approach 2:
The tapered portion introduces a dimensional variation in the adhesive application area, creating a three-dimensional structure that accommodates air bubbles vertically without affecting the horizontal insulation gap. This dimensional change allows the adhesive to fill the bonding space while maintaining precise insulation quality at the critical interface
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 effectively secures insulating properties by preventing air bubbles from contacting the resin insulating layer, ensuring adequate creepage distance and preventing adhesive seepage, thereby enhancing the reliability and performance of the power semiconductor module.
Implementation Method 1
an adhesive with which the resin-insulated base plate is bonded to the case, the adhesive filling a tapered portion enclosed by the resin-insulated base plate and the case and formed on the case closer to the resin-insulated base plate
Data Source
AI summary
Provided is a power semiconductor module that can secure insulating properties. A semiconductor element is mounted on a resin-insulated base plate including a circuit pattern, a resin insulating layer, and a base plate. A case enclosing the resin-insulated base plate is bonded to the resin insulating layer with an adhesive. The resin insulating layer and the case are bonded together with a region enclosed by the resin insulating layer and a tapered portion of the case formed closer to the resin insulating layer being filled with the adhesive made of a material identical to that of the sealing resin. Air bubbles in the adhesive appear in the tapered portion opposite to the resin insulating layer.