• 文献标题:   Radio Frequency Performance Projection and Stability Tradeoff of h-BN Encapsulated Graphene Field-Effect Transistors
  • 文献类型:   Article
  • 作  者:   FEIJOO PC, PASADAS F, IGLESIAS JM, HAMHAM E, RENGEL R, JIMENEZ D
  • 作者关键词:   graphene fieldeffect transistors gfets, hexagonal boron nitride hbn encapsulated graphene, negative differential resistance ndr, radio frequency rf, stability
  • 出版物名称:   IEEE TRANSACTIONS ON ELECTRON DEVICES
  • ISSN:   0018-9383 EI 1557-9646
  • 通讯作者地址:   Univ Autonoma Bacelona
  • 被引频次:   4
  • DOI:   10.1109/TED.2018.2890192
  • 出版年:   2019

▎ 摘  要

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-basedRF 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.