Electrode Orientation Dependent Transition Metal-(MoS2; WS2) Contact Analysis for 2D Material Based FET Applications

A Density Functional Theory based simulation study on cubic crystal orientation dependent transition metal contact with monolayer MoS2/WS2 in reference to exchange energy, density of states and thermodynamic entropy measurements are studied. Exchange energy states the stability of the interfaces between MoS2/WS2 and transition metals. The density of states calculation reveals the transport dominance with respect to charge polarity (electron or hole) and magnitude of charge flow through the interface. Entropy gives an alternative view to analyse carrier-phonon scattering at the interface. Our calculations suggest that (100) and (111) orientated transition metals from 3d group like Sc, Ti, Cr, Co, and Ni, (110) orientated transition metals from 4d group like Tc, Pd, Zr, and Ag and from 5d group (100), (110) orientated elements like Ta, W, Os, Ir, Pt are better suited for elemental contact applications in MoS2 and WS2 channel-based CMOS logic FETs.