Short Circuit Robustness of an Aged High Power IGBT-Module

The capability of an unused high-power IGBT Module to withstand a short circuit type 1 is most likely given for a duration of t
_sc
≤ 10 μs at high temperatures ϑ=150 °C. If this robustness is maintained for a severely aged device was investigated in this paper. Ageing up to a certain amount of remaining lifetime was realized within a Power Cycling Test (PCT). The PCT conditions were chosen in order to stress the bond wire connections, because it was assumed that the bond wire condition and chip surface metallization are limiting the short circuit capability. The obtained results show that the capability to withstand a short circuit event for a certain duration tSC does not decrease towards End of Life (EoL). However, the critical energy applied during short circuit tSC_cirt without destruction decreases with respect to ageing. One measurement revealed a decrease of short circuit robustness even within the safe operating area (SoA) specified in the datasheet.