We have investigated the electron mobility in ultrathin-body InGaAs-on-insulator devices using physics-based modeling that self-consistently accounts for quantum confinement and covers band-structure effects in ultrathin III-V layers. Scattering by nonpolar and polar acoustic and optical phonons, surface roughness, and thickness fluctuations, Coulomb and alloy disorder have been included in the calculations. The modeling, calibrated and verified on experimental data from the literature, has revealed a strong influence of thickness fluctuations caused by the light effective mass of Γ valley electrons. Our results indicate that InGaAs-on-insulator MOSFETs are more influenced by interface properties compared with silicon-on-insulator devices and outperform them only above certain body thickness that depends on interface quality.

We present an extensive study of the electronic properties and carrier transport in phosphorene nanoribbons (PNRs) with edge defects by using rigorous atomistic quantum transport simulations. This study reports on the size- and defect-dependent scaling laws governing the transport gap, and the mean free path and carrier mobility in the PNRs of interest for future nanoelectronics applications. Our results indicate that PNRs with armchair edges (aPNRs) are more immune to defects than zig-zag PNRs (zPNRs), while both PNR types exhibit superior immunity to defects relative to graphene nanoribbons (GNRs). An investigation of the mean free path demonstrated that even in the case of a low defect density the transport in PNRs is diffusive, and the carrier mobility remains a meaningful transport parameter even in ultra-small PNRs. We found that the electron–hole mobility asymmetry (present in large-area phosphorene) is retained only in zPNRs for W > 4 nm, while in other cases the asymmetry is smoothed out by edge defect scattering. Furthermore, we showed that aPNRs outperform both zPNRs and GNRs in terms of carrier mobility, and that PNRs generally offer a superior mobility-bandgap trade-off, relative to GNRs and monolayer MoS₂. This work identifies PNRs as a promising material for the extremely scaled transistor channels in future post-silicon electronic technology, and presents a persuasive argument for experimental work on nanostructured phosphorene.

Atomistic quantum transport simulations of a large ensemble of devices are employed to investigate the impact of different sources of disorder on the transport properties of extremely scaled (length of 10 nm and width of 1-4 nm) graphene nanoribbons. We report the dependence of the transport gap, on- and off-state conductances, and on-off ratio on edge-defect density, vacancy density, and potential fluctuation amplitude. For the smallest devices and realistic lattice defect densities, the transport gap increases by up to ~300%, and the on-off ratio reaches almost ~10⁶ . We also report a rather high variation of the transport gap and on-off ratio. In contrast, we find that the potential fluctuations have a negligible impact on the transport gap and cause a relatively modest increase of the on-off ratio.

We use atomistic quantum transport device simulations to investigate the contact resistance ( R _C ) in monoelemental 2D material nanoribbon MOSFETs with edge contacts. The consequences of attaching metal electrodes to source/drain regions are investigated for various metal-channel interaction strengths and nanoribbon dimensions. We find that R _C is minimized by using moderately interacting metallic materials, and that the minimum R _C is ~ 150 Ω·μm in graphene, silicene and germanene, and ~ 430 Ω·μm in phosphorene nanodevices with edge contacts.