A Die Attach Design for Thermoelectric Generator Packages for Automotive Applications

The requirement to achieve high reliability for the die attach in thermoelectric generator (TEG) package design is key to their viability and safe operation in automotive applications. In this study, the reliability of die attach material Al 718 (88% Al, 12% Si) during high temperature operating conditions is discussed. A novel approach is outlined to determine the damage parameter for accurate reliability predictions using a scalable test vehicle fabrication, testing, and finite element analysis (FEA) simulations. In addition, a new TEG package design is proposed that can withstand extreme environmental conditions and exhibit enhanced mechanical reliability by minimizing the likelihood that sublimation and oxidation of the semiconductor dies occurs. The proposed design of TEGs is analyzed using finite element simulations. Prototype models were fabricated and tested to validate the computational predictions. Continuum damage mechanics was used to predict the fatigue life of TEG packages using computational modeling of cyclic damage evolution. The results demonstrated that the proposed die attach design can be commercially viable for high-temperature TEG applications.