Double-Sided Power Switch Module With Wire-Bondless Gate Connections
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current power switch modules face challenges with unreliable electrical connections due to mechanical stress, high manufacturing complexity, and inefficient thermal management, particularly in high-voltage and multi-phase converter applications, where wire-bonding and multiple solder pastes increase parasitic inductances and reduce reliability.
Innovation Solution
The implementation of a hybrid power switch module configuration with pressure-based contacts, such as spring pins, and multi-functional components (MFCs) that serve as both bus-bars and heat-sinks, integrated in a compact package with optimized layout to reduce inductances and enhance thermal management, using a simplified two-solder-paste cascade soldering process for cost-effective and reliable manufacturing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If wire-bonding is used for electrical connections in power switch modules, then electrical connectivity is established, but parasitic inductances increase and reliability decreases under mechanical stress
Solution Approach 1:
The patent removes wire-bonding from the power switch module design and replaces it with direct soldered connections between power semiconductor devices and PCB traces. This extraction eliminates the wire-bonding layer that generates parasitic inductances, achieving lower inductance values while maintaining reliable electrical connectivity through robust solder joints that withstand mechanical stress
Solution Approach 2:
The patent replaces the mechanical wire-bonding system with a solder-based electrical connection system. Instead of using mechanical wire bonds that are susceptible to fatigue and stress, the invention uses soldered traces on the PCB that provide both electrical connectivity and mechanical robustness, eliminating the harmful mechanical stress concentration points
2Manufacturing precision
If multiple solder pastes are used in cascade soldering process, then manufacturing precision is improved, but device complexity and manufacturing time increase
Solution Approach 1:
The patent employs a single solder paste formulation that can handle all soldering operations in the cascade process, from attaching power semiconductor devices to mounting the entire assembly on the PCB. This universal solder paste approach maintains manufacturing precision while eliminating the complexity of managing multiple solder paste types, their respective temperature profiles, and changeover procedures
Solution Approach 2:
The patent modifies the solder paste parameters (composition, melting point, flow characteristics) to create a single versatile solder paste that can accommodate all soldering stages. By adjusting the solder paste formulation to have appropriate reflow characteristics and adhesion properties, the invention achieves precise soldering results without requiring multiple specialized solder pastes
3Volume of stationary object
If components are arranged in compact configuration, then package volume is reduced, but thermal management becomes more challenging
Solution Approach 1:
The patent merges the thermal management function with the electrical connection structure by using the PCB traces and power semiconductor device mounts as both electrical conductors and heat conduction paths. The solder joints serve dual purposes of electrical connectivity and thermal transfer, eliminating the need for separate thermal management components and enabling compact packaging while maintaining effective heat dissipation
Solution Approach 2:
The patent implements multi-functional PCB traces and mounting structures that simultaneously provide electrical connectivity, mechanical support, and thermal conduction. The power semiconductor device mounts serve as both electrical connection points and heat sinks, while PCB traces function as both signal/power carriers and thermal pathways, achieving compact design without compromising thermal management
4Reliability
If pressure-based contacts are added to strengthen critical connections, then reliability under mechanical stress improves, but manufacturing complexity increases
Solution Approach 1:
The patent combines the pressure-based contact function with the existing soldered connection structure. By designing the PCB and power semiconductor device mounts to provide inherent mechanical pressure through their rigid structure and precise fitment, the invention achieves reliable stress-resistant connections without adding separate pressure-based contact components, thereby avoiding increased manufacturing complexity
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 configuration provides highly reliable electrical connectivity and improved thermal management, enabling efficient operation in high-voltage and multi-phase converters with reduced parasitic inductances and manufacturing complexity, while maintaining optimal switching performance and scalability.
Implementation Method 1
the critical connections between the components are strengthened by pressure-based contacts to withstand external mechanical stimuli
Implementation Method 2
thermo-electrically conducting spacers and thermo-electrical MFCs... with the bare-die switch modules wire-bondlessly attached to opposite sides of a shared main Printed Circuit Board (PCB) assembly
Implementation Method 3
a simplified two-solder-paste cascade soldering process
Data Source
AI summary
A hybrid double-sided power switch module comprises a double PCB assembly with switch dies and conductive spacers disposed at both sides of the double PCB assembly in different topologies. The gate connections of the switch dies are enhanced by spring pins soldered in the THVs formed through the PCBs in alignment with the gate terminals. MFCs are positioned at both sides of the double PCBs assembly in contact with the tops of the switch dies and conductive spacers with fuzz buttons serving as contacts between the MFCs and the switch dies and spacers. MFCs serve different functions including AC bus-bars, DC bus-bars, heat-sinks, and their combination. The module can withstand external stress and is fabricated by a simplified and inexpensive process requiring only two solder pastes.