Electrothermal Analysis of a Double-Side Cooling Power Module With Large-Area SiC MOSFETs

SiC MOSFETs typically have a small chip area compared to conventional Si IGBTs. The performance of large-area (<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$10 \times 10$ </tex-math></inline-formula> mm) SiC MOSFETs needs to be investigated. In this article, the electrothermal analysis of the large-area SiC MOSFETs is presented compared to regular-sized (<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$5 \times 5$ </tex-math></inline-formula> mm) SiC MOSFETs in paralleling. The result shows that the large-area chips optimize the packaging parameters, mitigate the current imbalance, and have better thermal performance in the double-side cooling (DSC) module compared to the regular-sized chips. A SOT-227 module with large-area chips is manufactured and the electrical performance of the module is tested. The result indicates the better electrical performance of modules using large-area chips. A novel flip-chip DSC module is proposed to take full advantage of the large-area chips. The proposed module is analyzed in terms of electrical and thermal characteristics compared to a conventional DSC module. The parasitic inductance of the proposed module is 5.36 nH for the power circuit and 4.93 nH for the signal loop, which is reduced by 29.1% and 13.7%, respectively. The temperature distribution is improved, and the thermal resistance of the proposed module is 0.268 K/W, which is reduced by 12.0%. The results show that the electrical and thermal performance of the proposed module is better than that of the conventional module.