Subthreshold swing characteristics of multilayer MoS2 tunnel FET

Subthreshold swing (S) is the figure of merit that determines the behavior of a transistor in the subthreshold region. The performance of the metal-oxide-semiconductor-field-effect transistor (MOSFET) is fundamentally limited by the thermal voltage (kT/q), which leads to the theoretical minimum of S = 60mV/decade. We have recently proposed a multilayer molybdenum disulfide (MoS₂) based tunnel transistor as a possible replacement of the conventional silicon MOSFET. MoS₂ is considered as the new super material for post-silicon technology. The proposed quantum mechanical band-to-band-tunneling (BTBT) mechanism based TFET with multilayer MoS₂ channel has the potential to achieve subthreshold swing below 60mV/decade. This paper provides a clear understanding of the subthreshold swing characteristics of the proposed device. In addition to explaining the underlying physics, this paper presents an analytical model of the subthreshold swing of the proposed device. The developed model reveals that the parameter S of the proposed TFET is independent of the thermal potential (kT/q), which means that the thermionic limitation of the conventional and emerging FETs will not affect the proposed device.