Substrate Integrated Temperature Sensing for Bondless Power Modules

Abstract:
The following paper presents an inexpensive and fast solution for temperature sensing in bondless power modules. This implementation utilizes the temperature-dependency of the resistance of a dedicated sensing trace in close proximity to the power semiconductor to detect the temperature. This approach enables lower response times and higher sensor temperatures, compared to discrete sensors, while maintaining a good linearity. Those attributes allow a thermal stress sensing for interconnect layers close to the chip. For evaluation, a SiC-MOSFET module with a sensing PCB mounted on top is built. Measurements show the highly linear sensitivity of 7.51m/K and the reduced response times of only 70 ms, compared to discrete sensors mounted on top of the top side substrate with 700 ms. To determine the performance in an application-focused design, a power module with ceramic top substrate is simulated.