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The hot carrier and ionizing radiation responses of 45-nm SOI RF nMOSFETs are investigated. Devices with “tight” source/drain (S/D) contact spacing have improved RF performance but degraded hot carrier reliability and radiation tolerance. Devices with “loose” gate finger-to-gate finger spacing have improved RF performance and also improved hot carrier and radiation tolerance. The effects of finger width on the hot carrier stress and ionizing radiation degradation of strained silicon-on-insulator RF MOSFETs are also investigated. Enhanced degradation is observed for devices with wide finger widths and is attributed to the greater channel-region mechanical stress induced impact ionization. This result is contrary to the previous studies which showed that narrow channel width devices should exhibit greater damage. Taken together, these results have serious consequences for RF circuits that require large widths for sufficient RF gain. Finally, devices with symmetric halo doping are observed to exhibit greater total-dose degradation than devices with asymmetric halo doping. [ABSTRACT FROM PUBLISHER]

We have examined the reliability risks of complementary SiGe HBTs on thick-film silicon on insulator (SOI). DC stress techniques, such as reverse emitter–base (EB) stress, mixed-mode stress, and flyback measurements, were used to characterize the safe operating area of n-p-n and p-n-p SiGe HBTs fabricated on SOI substrates. The measurements were analyzed based on fundamental damage mechanisms, such as hot carriers generated at the EB and collector–base junctions during large reverse voltage, and thermal runaway as a result of high current phenomena. RF stress (using a large amplitude continuous-wave signal) was also performed to examine the reliability of complementary bipolar complementary metal–oxide–semiconductor devices and circuits in an RF context. In both cases, p-n-p SiGe HBTs were found to be more reliable than n-p-n SiGe HBTs, a fact that may offer opportunities for circuit design optimization. [ABSTRACT FROM PUBLISHER]