Abstract
In this paper, the degradation mechanism of the RF performance of 22 nm fully depleted (FD) silicon-on-insulator nMOSFETs at different total ionizing dose levels has been investigated. The RF figures of merit (the cut-off frequency f(T), maximum oscillation frequency f(max)) show significant degradation of approximately 14.1% and 6.8%, respectively. The variation of the small-signal parameters (output conductance (g(ds)), transconductance (g(m)), reflection coefficient (|Γ(in)|), and capacitance (C(gg))) at different TID levels has been discussed. TID-induced trapped charges in the gate oxide and buried oxide increase the vertical channel field, which leads to more complex degradation of small-signal parameters across a wide frequency range.