Laser-Welded SMD Power Module Connections for High Current Reliability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing SMD power semiconductor components face limitations in current carrying capacity and reliability due to heating issues from high amperage, particularly when using soft solder connections on circuit carriers like PCBs or IMS substrates, which hinder efficient operation and require current reduction to maintain reliability.
Innovation Solution
The method involves laser welding discrete power semiconductor components with conductive connection elements onto an SMD circuit carrier, ensuring mechanical and electrical fastening on the same side, using a monometallic bond to enhance current carrying capacity and reliability, allowing operation at higher amperages and temperatures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If soft solder connections are used to mount power semiconductor components on circuit carriers, then ease of manufacture is improved, but current carrying capacity and reliability deteriorate due to heating issues from high amperage
Solution Approach 1:
The patent changes the connection method from soft soldering to laser welding, which fundamentally alters the physical and chemical parameters of the joint. Laser welding creates a metallurgical bond with different thermal and electrical properties compared to solder joints, enabling higher current carrying capacity and reliability while maintaining manufacturing efficiency through automated laser processes
2Ease of manufacture
If soft solder connections are used to mount power semiconductor components on circuit carriers, then ease of manufacture is improved, but current carrying capacity deteriorates due to small copper cross-sections and ohmic resistances
Solution Approach 1:
The invention changes the connection technology from soldering to laser welding, which enables larger effective cross-sections for current flow and reduces ohmic resistances. The laser welding process creates direct metal-to-metal bonds that provide lower resistance pathways for high current flow compared to solder joints with small copper cross-sections
3Ease of manufacture
If mechanical fastening and electrical contacting are performed on different sides of the circuit carrier, then ease of manufacture is improved, but device complexity increases
Solution Approach 1:
The patent merges the mechanical fastening and electrical contacting functions into a single laser welding operation performed on one side of the circuit carrier. This consolidation eliminates the need for separate fastening and contacting planes, reducing the number of components and assembly steps while maintaining manufacturing simplicity through automated laser processes
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
This approach improves current carrying capacity and reliability by reducing ohmic resistance, enabling sustainable operation under high load conditions and maintaining full performance without limitations, especially suitable for IMS substrates with enhanced cooling functions.
Implementation Method 1
connecting the connection elements to the respectively assigned contact points by laser welding
Implementation Method 2
The electrical connection of the power semiconductors and the contact points of the substrate are made by soldering in a reflow process
Data Source
AI summary
A method for producing an SMD power semiconductor component module includes providing an SMD circuit carrier equipped with contact points and an insulation, and at least one discrete power semiconductor component equipped with electrically conductive connection elements, preferably connection legs. The at least one discrete power semiconductor component, equipped with electrically conductive connection elements, is arranged on the side of the SMD circuit carrier equipped with the contact points. The connection elements of the power semiconductor component contact the contact points of the SMD circuit carrier, and the connection elements are connected to the respectively assigned contact points by laser welding.