Kudina V. Origin of the fluctuation processes in advanced field effect transistors.

The thesis deals with investigation of the low-frequency noise of advanced silicon-in-insulator (SOI) metal-oxide-semiconductor field effect transistors (MOSFETs). The noise characterization of fully depleted planar MOSFETs with SiON gate oxide and three-gate finFETs with high-k dielectric based gate stacks (HfSiON, HfO2) is implemented. It is found that the McWhorter noise is typical for the devices considered. This observation allowed determining the distributions of trap densities over the distance into the gate dielectrics. In addition the impact of biaxial (sSOI) and uniaxial (CESL) strain on the low-frequency noise behaviour of the devices studied is revealed. The effects of high gate voltage drain current leveling off and nontrivial drain current dimensional dependence were found for the devices investigated and explained by means of the noise measurements. It is revealed that finFETs are sensitive to floating body noise effects (Lorentzian noise). By analyzing them using the method proposed, the intrinsic finFET parameters were found. The influence of twin-gate configuration of partially depleted MOSFETs on their low-frequency noise accompanying floating body effects was found and explained by the model developed. It is shown that the suppression of such noise effects in single-gate analogs can be achieved by applying an accumulation back-gate voltage. This effect is explained in the framework of the model proposed.