A center-potential-based threshold voltage model for a graded-channel dual-material double-gate strained-Si MOSFET with interface charges

Analytical modeling of subthreshold current and swing of strained‐Si graded channel dual material double gate MOSFET with interface charges and analysis of circuit performance

“…It is observed that the s-Si GC-DMDG device offers lower I s than s-Si GC-DG device due to the larger V th of s-Si GC-DMDG device over s-Si GC-DG MOSFET. 22 Moreover, the effect of V ds on I s of s-Si GC-DMDG MOSFET is less compared to s-Si GC-DG MOSFET as the variations of V ds are screened by the step-like center channel potential of s-Si GC-DMDG MOSFET. On the other hand, I s of s-Si GC-DG device is increased by increasing the V ds due to drain induced barrier lowering (DIBL) effect.…”

“…It is clear from Figure 1B that the TCAD simulation results of s-Si MOSFET is in good agreement with the Reference 25. Moreover, the present work is a continuation of our recently presented work 22 and the same notations are used for device parameters to ease the transition. Also, some of the results in Reference 22 are directly used for modeling the SS and SC of s-Si GC-DMDG MOSFET.…”

“…where (V fbr, oc ) s -Si is the flat band voltage between gate and s-Si channel with interface charge density. With the help of boundary conditions, the center channel potential, ψ rc (x) of s-Si GC-DMDG MOSFET with fixed charges corresponding to region r has already been derived from Poissons equation in our previous work 22 and once again, here, it is exploited for modeling the subthreshold current and subthreshold swing as follows…”

“…where ψ r,min y ð Þ = ∂ψ r x, y ð Þ ∂x j x = x min is the minimum channel potential at the virtual cathode 22 corresponding to region r. x min is the position of minimum channel potential in channel region (x-axis). x min is varied from region 2 to region 4 with respect to work function of gate materials and positive (negative) interface charge density with damaged length.…”

“…However, so far, no work has presented the analytical model for the SC and SS of s-Si GC-DMDG MOSFET with fixed charges. 22 In CMOS technology, the static power dissipation dominates the dynamic power dissipation in short channel devices (generally <100 nm). Besides, the leakage current is the dominating parameter in static power consumption.…”