Conference Agenda

Power electronic components play a major role in many industries with applications in automotive, aerospace, and railway transportation. With the increasing demand, reliability and efficiency constraints that come from the growth in lifetime expectation and safety requirements are major challenges of these devices.

Thermal cycling is a common phenomenon occurring in power electronic (PE) modules during operation and results in failure due to a mismatch of the Coefficient of Thermal Expansion (CTE) between interconnecting components with different materials. One such failure is due to the increase in junction temperature of the module triggering degradation. A common type of failure found in PE modules is from the separation of layers known as delamination. This paper proposes a concept that helps in minimizing delamination propagation after a certain threshold by giving feedback on reducing input conditions.

The power electronic module investigated is a MOSFET equipped with silicon carbide (SiC) semiconductor that operates in high temperature and high frequency used in automotive applications. The Accelerated aging test is widely recognized as the most common and efficient method for the determination of the reliability of a PE component. Active power cycling test which is one of the prominent types of accelerated aging test is used for both experimental validation and simulation purposes.

A 3D finite element (FE) sub-model is developed using ANSYS software to simulate the electrothermal behavior of the PE module. Percentage of total delaminated area in die attach solder layer is considered as a criterion for finite element simulation and the resulting junction temperature is studied. The obtained junction temperature of the module is compared to that of the experimental test and certain adjustments in the boundary condition of the FE model are initiated as part of the calibration. Criteria is defined in such a way that a 20% increase in thermal resistance and a 5% increase in drain-source voltage enable determination of the current state-of-health (SoH) of the module. With the determination of SoH, the remaining useful life (RUL) of the module can be obtained.

The next phase involves the possibility of the extension of service life by adjusting operating loads in such a way that it would further reduce the junction temperature. In Design of experiment (DoE) study of the calibrated model, various simulations were conducted with different input conditions such as current as loading condition, coolant temperature for environment condition and delamination as damage condition are simulated and resulting junction temperature, thermal resistance, and drain-source voltage are investigated. From the DoE study, the response surface as a compact model is developed that acts as a surrogate model providing efficient and instant prediction of system behavior that can be used for monitoring the failure risk of the module.

The precision and reliability of MEMS devices critically depend on the quality of their hermetic sealing processes, particularly in applications requiring stringent vacuum conditions. In order to maintain optimal device functionality over extended periods, it is essential to achieve high vacuum levels with minimal residual gas contamination. This work presents advancements in MEMS packaging technology enabled by a redesigned dual-chamber thermal getter system and the introduction of a novel tooling material, which together contribute to improved sealing precision and long-term vacuum stability.

The SRO Getter system is specifically designed to both hermetically seal MEMS packages and activate the getter material within the package, ensuring optimal environmental conditions for device longevity. The enhanced system architecture isolates getter activation from package sealing, enabling independent optimization of process parameters. This separation allows for more controlled processing conditions, reducing unintended interactions between different stages of the packaging process. The incorporation of the new tooling material significantly improves temperature uniformity during thermal processing, ensuring precise heat distribution across the package. Improved thermal consistency reduces localized overheating and thermal gradients, which are critical factors in ensuring the integrity of MEMS devices. Additionally, an active cooling system has been integrated to speed up cooling in high-vacuum conditions, allowing for better control over intermetallics formation. By managing cooling rates more effectively, the system mitigates material diffusion effects that could otherwise impact the mechanical and electrical properties of the final sealed package. These improvements result in better control over the sealing process, increased yield, and improved reproducibility.