Thermomechanical Analysis of SiC Power Module Based on Insulating Metal Substrate with High Thermal Conductivity Epoxy Resin

• Main Authors: Lin, Yongtai, Mao, Yinjie, Lei, Guangyin
• Format: Conference Proceeding
• Language: English
• Subjects: active metal brazing substrate; Conductivity; Epoxy resins; Fluctuations; high thermal conductivity epoxy resin; insulating metal substrate; Metals; Multichip modules; Silicon carbide; silicon carbide power module; Thermal resistance
• ISSN: 2836-9734
• DOI: 10.1109/ICEPT63120.2024.10668467

This article presents a power module based on thick-copper insulating metal substrate (IMS), where epoxy resin (EP) with high thermal conductivity, ranging from 1 (W/mK) to 15 (W/mK), is used as the insulation layer. A 2.5mm thick-copper layer under the power device is adopted for high thermal capacity, which is crucial to reduce the transient temperature swing of the power module, especially for operating in heavy-load with high pulse current. Compared with the conventional structure based on Si 3 N 4 -AMB (active metal brazing) substrates, the proposed power module with IMS substrate allows a similar thermal resistance when the thermal conductivity of the EP layer reaches 3.97 (W/mK), for the specific power module built for this study. Moreover, when the EP reaches a thermal conductivity of 15 (W/mK), the IMS-based power module would enable a junction temperature 12.86% lower than the one based on Si 3 N 4 -AMB. In addition, the thermal time constant of the IMS-based module is 244.87% longer than the one built on the AMB substrate, allowing a 15°C reduction in temperature swing when 50 W of power cycles is applied, which is crucial for the thermomechanical reliability of the power module.