Degradation and reliability of silicon power transistors

The degradation of silcon power transistors (RESURF LDMOS type) are studied under high voltage off-state and on-state stress conditions. The deterioration of the devices is shown to be hot-carrier dominated. Hot carrier damage occurs at the drain side of the drift region and leads to changing I-Vcurves in two distinct regimes. With a non-invasive low-voltage leakage characterization the surface generation velocity profiles after stress can be extracted. These enable predictions of the I-V behaviour across a wide temperature range, and may be used for reliability projections of these devices.