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# The signal-to-noise ratio of 5.9 mV signal estimated for the single-trap phenomena approach for different conditions. (a) The S/N ratio is calculated for the time windows = 1s and = 10s , and plotted as a function of RTS corner frequency. (b) The S/N ratio vs. g for different g-factor slopes and 10 s time window. The dashed line represents the S/N level calculated for the Si NW FET with DP voltage noise of 1.4 × 10 -8 V 2 /Hz at 10 Hz. The arrow indicates the S/N ratio enhancement for the single-trap phenomena approach.

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Transistor biosensors are mass-fabrication-compatible devices of interest for point of care diagnosis as well as molecular interaction studies. While the actual transistor gates in processors reach the sub-10 nm range for optimum integration and power consumption, studies on design rules for the signal-to-noise ratio (S/N) optimization in transisto...

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Context 1
... S/N ratio calculated for RTS noise with different corner frequencies at g = 0.5 is shown in Fig. 6a. A larger number of transition events due to the higher RTS rate ( γ = πf 0 ) results in smaller S gg noise (see Fig. 5b) which leads to the increase of the S/N ratio. Figure 6b demonstrates the S/N ratio calculated for RTS phenomena with different g-factor slopes (see Fig. 5c). The dashed line reflects the S/N level for the trap-free ...
Context 2
... larger number of transition events due to the higher RTS rate ( γ = πf 0 ) results in smaller S gg noise (see Fig. 5b) which leads to the increase of the S/N ratio. Figure 6b demonstrates the S/N ratio calculated for RTS phenomena with different g-factor slopes (see Fig. 5c). The dashed line reflects the S/N level for the trap-free device with the same gate capacitance as for one with the single trap demonstrating DP noise only. ...
Context 3
... The dashed line reflects the S/N level for the trap-free device with the same gate capacitance as for one with the single trap demonstrating DP noise only. As a signal, we used the threshold voltage shift of 5.9 mV caused by 0.1 pH change in the gating solution when considering ideal ion-sensitive FET-based sensors. It can clearly be seen from Fig. 6a,b that under optimized conditions the S/N ratio can indeed substantially be increased even above the level expected for trap-free devices monitoring the threshold voltage shift as a signal. ...
Context 4
... best performance is obtained for a trap occupancy probability averaged over many events. The trap operation frequency is not easy to control, even though progress has been reported towards "on-demand" trap generation 23 . Instead, a simple way to increase the trap operation frequency is to consider a larger g-factor by tuning the gate bias (see Fig. 6b). This comes from the fact that τ e is almost constant (see Fig. 4b) and therefore, at relatively high g , RTS corner frequency f 0 ≈ 1/(2πτ c ) . The alternative is to play with the slope of g (Fig. 5d). In principle, the slope is only determined by the temperature (Fermi-distribution), and the trap depth (potential drop in the ...

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