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Hexagonal boron nitride encapsulation significantly improves carrier transport in graphene. This paper investigates the benefit of implementing the encapsulation technique in graphene field-effect transistors (GFETs) in terms of their intrinsic radio frequency (RF) performance, adding the effect of the series resistances at the terminals. For such a purpose, a drift-diffusion self-consistent simulator is prepared to get the GFET electrical characteristics. Both the mobility and saturation velocity are obtained by an ensemble Monte Carlo simulator upon considering the relevant scattering mechanisms that affect carrier transport. RF figures of merit are simulated using an accurate small-signal model. Results reveal that the cutoff frequency could scale up to the physical limit given by the inverse of the transit time. Projected maximum oscillation frequencies, in the order of few terahertz, are expected to exceed the values demonstrated by InP and Si-based RF transistors. The existing tradeoff between power gain and stability and the role played by the gate resistance are also studied. High power gain and stability are feasible even if the device is operated far away from current saturation. Finally, the benefits of device unilateralization and the exploitation of the negative differential resistance region to get negative-resistance gain are discussed. [ABSTRACT FROM AUTHOR]

This paper presents a detailed Monte Carlo study of the optimization of the dopant segregation (DS) layer in n-type Schottky barrier (SB)-MOSFET. It is shown that with a careful control of the DS layer parameters, dopant concentration (N dop ), and length (L dop ), the performance of the devices is significantly enhanced. The presence of the DS layer induces crucial effects in the injection processes at the Schottky contacts. The benefits of increasing the length and the doping level of the DS layer are studied from the microscopic point of view (transit times, average number of scatterings). The effect of varying these parameters is also analyzed through the nonquasi-static parameters of the small signal equivalent circuit, which can be useful for designers to improve the reliability of the SB-MOSFET technology. [ABSTRACT FROM AUTHOR]