Bias Dependence of Total Ionizing Dose Effects in SiGe

The total ionizing dose (TID) response of double-gate SiGe- MOS FinFET devices is investigated under different device bias conditions. Negative bias irradiation leads to the worst-case degradation due to increased hole trapping in the layer, in contrast to what is typically observed for devices with or gate dielectrics. This occurs in the devices be- cause radiation-induced holes that are generated in the inter- facial layer can transport and become trapped in the under negative bias, leading to a more negative threshold voltage shift than observed at 0 V bias. Similarly, radiation-induced electrons that are generated in the interfacial layer can transport into the and become trapped under positive bias, leading to a more positive threshold voltage shift than observed at 0 V bias. Index Terms—Double-gate FinFETs, ,S iGe, threshold voltage shift, total ionizing dose.