Back bias influence on low-frequency noise of n-type nanowires SOI MOSFETs

This work presents the influence of back (substrate) bias on the low-frequency noise of fully depleted inversion mode n-FET nanowire transistors with different fin widths. Several gate voltage overdrives were applied (from 0mV to 200mV) with devices working in linear regime. The results showed a noise increase for both positive and negative substrate biases (V_sub) and the changing of γ, from 0.9 with zero back bias down to 0.4 for V_sub = -40V. The results obtained for device with channel length of 1μm and fin width of 15nm show a decrease of the spectral noise density with the gate voltage overdrive increase for frequencies below 100Hz, which is characterized by mobility mechanism influence at the power spectrum density noise. It was also possible to see in these devices that the generation and recombination noise with decay of 1/f² overlaps the 1/f^γ noise for frequencies above 100Hz. It was also possible to see the noise increase with W_fin decrease as expected.