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We have measured the low-frequency 1/ f noise of Si0.55Ge0.45 p MOSFETs with a Si capping layer and SiO2/HfO2/TiN gate stack as a function of frequency, gate voltage, and temperature (100–440 K). The magnitude of the excess drain voltage noise power spectral density ( \textitS {vd} ) is unaffected by negative-bias-temperature stress (NBTS) for temperatures below ~250 K, but increases significantly at higher temperatures. The noise is described well by the Dutta-Horn model before and after NBTS. The noise at higher measuring temperatures is attributed primarily to oxygen-vacancy and hydrogen-related defects in the SiO2 and HfO2 layers. At lower measuring temperatures, the noise also appears to be affected strongly by hydrogen-dopant interactions in the SiGe layer of the device. [ABSTRACT FROM PUBLISHER]

The total ionizing dose response of Ge channel pFETs with raised Si0.55Ge0.45 source/drain is investigated under different radiation bias conditions. Threshold-voltage shifts and transconductance degradation are noticeable only for negative-bias (on state) irradiation, and are mainly due to negative bias-temperature instability (NBTI). Nonmonotonic leakage changes during irradiation are observed, which are attributed to the competition of radiation-induced field transistor leakage and S/D junction leakage. [ABSTRACT FROM PUBLISHER]

The total ionizing dose (TID) response of double-gate SiGe-SiO_2/HfO_2 \ pMOS 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 HfO_2 layer, in contrast to what is typically observed for devices with SiO_2 or HfO_2 gate dielectrics. This occurs in the devices because radiation-induced holes that are generated in the SiO_2 interfacial layer can transport and become trapped in the HfO_2 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 SiO_2 interfacial layer can transport into the HfO_2 and become trapped under positive bias, leading to a more positive threshold voltage shift than observed at 0 V bias. [ABSTRACT FROM PUBLISHER]

Electrical stress and 10-keV x-ray irradiation and annealing responses are evaluated for back-gate MoS2 transistors. Relative stability of device characteristics is observed for constant-voltage stress. The drain current decreases significantly after both positive and negative bias irradiation. Density functional theory calculations and ozone exposure experiments suggest that O atoms adsorbed on the MoS2 surface during 10-keV x-ray irradiation function as electron traps, causing mobility degradation and voltage shifts. [ABSTRACT FROM PUBLISHER]