DEGRADATION IN THIN-FILM SOI MOSFETS CAUSED BY SINGLE-TRANSISTOR LATCH

We report the measurement of anomalous hot-carrier damage in thin-film n-channel SOI MOSFET’s. Due to the presence of a parasitic bipolar transistor between the source and drain, the minimum drain voltage for breakdown in these devices occurs when the device is biased in subthreshold. Using charge-pumping measurements, we show that if the device is biased in this regime, where single-transistor latch occurs, hot holes are injected into the gate oxide near the drain. We conclude that the maximum allowable drain voltage for these devices is governed by the parasitic bipolar properties of the SOI MOSFET. © 1990 IEEE