SiC Power Module Layout for High-Frequency Low-Loss Switching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing power modules, particularly those using silicon-based minority carrier devices, face limitations in switching frequency, high switching and power losses, and require soft switching, which restrict their performance and cost-effectiveness for high-power applications.
Innovation Solution
The use of majority carrier transistors and diodes formed from a wide bandgap material system, such as silicon carbide (SiC), which allows for higher switching frequencies, lower switching losses, and the ability to handle hard-switching without additional circuitry, as seen in a six-pack power module configuration with SiC MOSFETs and junction barrier Schottky diodes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If silicon-based minority carrier devices are used in power modules, then the device structure is well-established and manufacturing is straightforward, but switching frequency is limited and switching losses are high
Solution Approach 1:
The patent changes the fundamental material parameter from silicon to wide bandgap materials (GaN, SiC), which fundamentally alters the carrier transport properties and enables high-frequency operation with low losses. This material parameter change allows the device to achieve both high switching frequency and low switching losses simultaneously, resolving the contradiction between speed and energy loss.
2Ease of manufacture
If silicon-based minority carrier devices are used, then manufacturing processes are成熟, but soft switching is required which limits performance
Solution Approach 1:
By changing from silicon to wide bandgap materials, the patent enables hard switching operation without requiring soft switching techniques. This parameter change in material properties allows direct switching capability while maintaining manufacturing feasibility through established semiconductor fabrication processes adapted for wide bandgap materials.
3Reliability
If bipolar devices are used to block high voltages, then drift layer resistance is reduced via conductivity modulation, but forward voltage degrades over time due to Basal Plane Dislocations
Solution Approach 1:
The patent employs composite material structures using wide bandgap materials (GaN or SiC) that inherently resist Basal Plane Dislocation formation. These materials combine high breakdown voltage capability with stable forward voltage characteristics, achieving both strong voltage blocking and reliable long-term performance without the degradation issues of silicon bipolar devices.
4Area of stationary object
If power module size is reduced, then manufacturing cost decreases and integration improves, but power handling capability is limited
Solution Approach 1:
By changing to wide bandgap materials with superior electrical properties, the patent achieves higher power density. The material parameter change enables smaller device dimensions while maintaining or increasing power handling capability, effectively resolving the contradiction between compact size and high power capacity.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A power module comprises: a baseplate (L0) comprising aluminum silicon carbide; a power substrate (L3) on the baseplate, the power substrate comprising silicon nitride; and a switch module (SM1 -SM10) mounted on the power substrate, the switch module comprising a silicon carbide transistor (Q1-Q10). The power module has a power density of up to 500 watts/cm2.