Impact of Orientation Misalignments on Black Phosphorus Ultrascaled Field-Effect Transistors

Two-dimensional materials with strong bandstructure anisotropy such as black phosphorus BP have been identified attractive candidates for logic application due to their potential high carrier velocity and large density-of-states. However, perfectly aligning the source-to-drain axis desired crystal orientation remains an experimental challenge. In this paper, we use advanced quantum transport approach from first-principle shed light on influence of misalignments performance BP-based field-effect transistors. Both $n$-and $p$-type configurations are investigated six alignment angles, in ballistic limit presence electron-phonon charged impurity scattering. It is found that up deviations $50^{\circ}$ optimal angle, ON-state current only decreases by $30\%$. This behavior explained considering a single parameter, effective mass along direction.