Fig. 3. Impact of density-of-states on SS_min and NC design space.

a SS_min at room temperature and b NC thickness design space (∆T_NC) for Si, Ga_0.47In_0.53As, and monolayer MoS₂. The effective DOS (conduction band) of Si and Ga_0.47In_0.53As are ~2.8 × 10¹⁹ cm⁻³ and ~2.1 × 10¹⁷ cm⁻³, respectively. The DOS of single-layer MoS₂ is ~2.4 × 10¹⁴ eV⁻¹·cm⁻². The low-DOS Ga_0.47In_0.53As exhibits significant advantages. C_div,<Vth and C_OX are normalized w.r.t the equivalent oxide thickness (EOT). c With the same device structure/size, Ga_0.47In_0.53As device can (in principle) achieve smaller SS, w.r.t. Si device, without hysteresis. SS of monolayer Germanane device can reach 39 mV per decade due to its low-DOS. The DOS of single-layer Germanane is ~2.9 × 10¹³ eV⁻¹·cm⁻².