A Novel High-Performance, High-Power Double-Sided Cooling SiC Power Module Based on Low-Temperature Pressureless Nano-Cu Sintering

Due to its low cost, excellent electrical and thermal properties, high reliability, and resistance to electromigration, nano-Cu sintering paste is regarded as the next-generation die interconnection material for wide-bandgap semiconductor applications. However, there are no experimental reports on the application of nano-Cu sintering in high-power double-sided cooling (DSC) SiC power modules. This work fills this gap by demonstrating the design, fabrication, and performance of a novel high-power DSC SiC MOSFET module based on nano-Cu sintering. Using self-prepared Cu paste and a formic acid-assisted low-temperature pressureless Cu sintering process, a 1200 V/600 A DSC power module is fabricated. When sintered in a formic acid atmosphere at a temperature of 250°C, the porosity of the sintered Cu is only 14.08%, and the shear strength reaches 42.5 MPa, twice that of traditional solder. Furthermore, the module exhibits superior switching performance, with switching losses reduced by more than 20% compared with similarly rated commercial module. Its power density reaches 6.70×10⁴ kW/L, while the total parasitic inductance is only 3.94 nH, a 40.3% reduction compared with commercial module. Additionally, the dense Cu sintering structure and low interfacial thermal resistance significantly enhance the thermal performance of the module, with a junction-to-case thermal resistance as low as 0.035 K/W, representing a 54.5% reduction compared with commercial module. These findings demonstrate the feasibility of applying the nano-Cu sintering process in high-power-density electronic devices.