Abstract

Conventional bulk MOSFETs are being replaced by potentially efficient multi-gate devices in very large scale integrated technology. Multi-gate MOSFETs offer better channel control and exhibit excellent scaling ability in the nanoscale regime. A Quadruple Gate (QG) MOSFET which is a prime variant of multi-gate MOSFETs is believed to provide better electrostatic integrity compared to a Double Gate (DG) MOSFET because of the gate surrounding the channel completely. Due to the structural advantage in a QG MOSFET, scattering effects are reduced and better quasi-ballistic behaviour is observed in the nanoscale regime. This work proposes a quasi-ballistic drain current model applicable for state of art symmetric QG MOSFET structures in the nanoscale regime. The proposed model evolves from the well known Natori’s ballistic theory and nanoscale carrier scattering theory. The drain bias dependency on the critical carrier scattering length is explored and applied to the proposed model successfully. The simulation results obtained demonstrate that the proposed model is physically apt, exhibits continuity in all regions of the device operation and hence can be adopted in multi-gate compact models for circuit simulation applications.

Authors

Vyas R Murnal,C. Vijaya
Sri Dharmasthala Manjunatheshwara College of Engineering and Technology, India

Keywords

Quadruple Gate MOSFET, Quasi-Ballistic Transport, Carrier Scattering, Compact Modeling