Study of ageing of the metallization layer of power semiconductor devices

Abstract: In order to accelerate the ageing of the metallization layer of power semiconductor devices, repetitive short circuit operations are applied to COOLMOS TM Transistors. Regularly, during repetition of short-circuit operations metallization is observed in a Scanning Electron Microscope which allows us to observe the process of cracking at the grain boundaries of the metallization layer. Different electrical characterizations were also done regularly and evolution of characterization results are linked to the metallization ageing in order to better understand the ageing process of the metallization layer and the effect of metallization layer ageing on the electrical performances. I