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An experimental investigation of two potential candidate materials for the diamond die attachment is presented in this framework. These efforts are motivated by the need of developing a power electronic packaging for the diamond chip. The performance of the designed packaging relies particularly on the specific choice of the solder alloys for the die/substrate junction. To implement a high temperature junction, AuGe and AlSi eutectic alloys were chosen as die attachment and characterized experimentally. The choice of the AlSi alloy is motivated by its high melting temperature T m (577 °C), its practical elaboration process and the restrictions of hazardous substances (RoHS) inter alia. The AuGe eutectic solder alloy has a melting temperature (356 °C) and it is investigated here for comparison purposes with AlSi. The paper presents experimental results such as SEM observations of failure facies which are obtained from mechanical shear as well as cyclic nano-indentation results for the mechanical hardening/softening evaluation under cyclic loading paths. [ABSTRACT FROM AUTHOR]

Mechanical suitability of ohmic contacts among the select metallization systems, deposited on a p-type heavily boron-doped homoepitaxial diamond layer, was evaluated via mechanical tests on the nanoscale. Two candidate metallization systems were considered: Si/Al and Ti/Pt/Au. Metallizations were performed using two different techniques: plasma-enhanced chemical vapour deposition and “lift-off”. Effectiveness of the techniques was assessed via mechanical tests on the microscale and the nanoscale. Nano-indentation experiments were performed to determine the mechanical properties of the layers. Nano-scratching experiments were used to evaluate the mechanical adhesion on the diamond substrate. Scanning electron microscopy was applied for observation of the morphology of the surface and the indent and for detecting defects. [ABSTRACT FROM AUTHOR]

Abstract: This work examines the thermal fatigue effects on different configurations of power modules used in harsh aeronautical environment. They are used in various applications where the temperature cycling due to the working environment is the most limiting fact. In this case, it is highlighted that the topology assembly choice is a critical point to reach the lifetime required for the final application. In addition, it is proposed to correlate the probabilistic finite elements calculus to the experimental accelerated ageing tests on test vehicle, in order to determine the best configuration of assembling stack consisting of baseplate/RoHS solder/metallized substrate. [Copyright &y& Elsevier]