Study of die attach technologies for high temperature power electronics: Silver sintering and gold–germanium alloy

•We compare 3 die-attach technologies for high temperature power electronics packaging.•Micro and nano silver sintering processes and AuGe solder alloy process are presented.•After high thermal ageing test, the results showed very high die shear strenght capability.•No evolution of the AuGe solder alloy joint is observed after 2500 thermal shocks cycles.•High range of temperature was used for the ageing test (-55°C to +245°C).

Silver sintering joints and AuGe soldering are promising technologies for high temperature (>200 °C ambient) power electronics packaging. This paper presents the implementation of two silver-sintering processes with the one hand micrometer-scale silver particles, and on the other hand nano-meter-scale particles. Two substrates technologies have been investigated: A12O3 DBC and Si3N4 AMB. After the process optimization, tests vehicles have been assembled using both sintering processes, as well as a more classical high-temperature die attach technology: AuGe soldering. Multiple analyses have been performed, such as thermal resistance measurement, shear tests and micro-sections to follow the evolution of the joint during thermal cycling and high-temperature storage ageing.