High-energy proton irradiation induced changes in the linear-kink noise overshoot of 0.10 μm partially depleted silicon-on-insulator metal-oxide-semiconductor field-effect transistors

This article describes the impact of a high-energy proton irradiation on the parameters of the Lorentzian noise overshoot, occurring in ultrathin gate oxide 0.10 μm partially depleted (PD) silicon-on-insulator metal-oxide-semiconductor field-effect transistors (MOSFETs), operated in the linear regime. It is shown that the drain current noise spectral density SI exhibits an increase after irradiation, while the Lorentzian time constant τ shows a different response to the 60/65 MeV protons in n- or p-channel transistors. In addition, the excess noise peak develops a pronounced radiation-induced dependence on the back-gate bias VBG, which is different for both device types: a strong increase of SI is found for the PD SOI p-MOSFETs, upon changing VBG into the accumulation regime, while in the first instance, the opposite is found for the n-MOSFETs. These observations are discussed in terms of a RC-filtered shot noise model and of the ionization induced positive charge trapping in the buried and isolation oxides. The results lead to the conclusion that in n-MOSFETs, an additional generation-recombination component becomes active by the charge trapping. In the p-type counterparts, on the other hand, it is believed that irradiation modulates the body-channel coupling factor, giving rise to a strong increase of SI with VBG, while the corresponding τ is in a first approximation not affected.