Noise characteristics of nanoscaled SOI MOSFETs

摘要

The low-frequency noise behavior of nanoscaled fully-depleted silicon-on insulator (SOI) finFETs is investigated and the perspectives of the noise method as a non-destructive diagnostic tool are revealed. The analysis of the (l/f)~γ McWhorter noise observed at zero back-gate voltage showed that the trap concentration N_(ot) appears to be lower in the case of devices with HfSiON/SiO_2 gate dielectric with the uniaxial strain in the inversion channel while the implementation of the HfO_2/SiO_2 gate stack and the biaxial strain tend to increase the value of N_(ot). The analysis of the back-gate-induced (BGI) and linear kink effect (LKE) Lorentzian noise observed when the back interface is biased in accumulation allowed to estimate the values proportional to equivalent capacitance C_(eq). Their front-gate voltage dependencies appear to be different for the devices with HfSiON/SiO_2 and HfO_2/SiO_2 gate dielectric. Also the values proportional to density of the electron-valence-band tunneling currents j_(EVB) were found for the devices studied. The influence of the strain-inducing techniques and gate dielectric type on the values discussed is revealed.