Layer-dependent Schottky contact at TaX2-BY (X = S, Se, Te; Y = P, As, Sb) van der Waals interfaces

The mechanical, thermal and dynamical stabilities, electronic structure, contact type, and height of the barrier at the interface of TaX2 (X = S, Se, Te) and BY (Y = P, As, Sb) metal-semiconductor (MS) contact are investigated via first principles calculations. Binding energies, mechanical properties, phonon spectra and ab initio molecular dynamics (AIMD) simulations confirm the stabilities of these systems. TaX2-BY (X = S, Se, Te; Y = P, As, Sb) MS van der Waals heterostructures (vdWHs) are found to be metal with a Schottky contact at the interface. Formation of the n-type Schottky contact at the interface of TaX2-BY (X = S, Se, Te; Y = P, As, Sb) MS vdWHs favors electron conduction over hole conduction. Small (higher) effective mass (carrier mobility) make TaS2-BSb, TaSe2-BSb and TaTe2-BSb MS vdWHs, potential candidates for high speed nanoelectronic applications. Bader charge analysis shows that at the interface of TaX2-BY (X = S, Se, Te; Y = P, As, Sb) MS vdWHs, in TaX2 (BP, BAs) the electrons transfer from the TaX2 layer to the BP and BAs layer, while in TaX2 (BSb) the electrons transfer from the BSb layer to TaX2 layer.The mechanical, thermal and dynamical stabilities, electronic structure, contact type, and height of the barrier at the interface of TaX2 (X = S, Se, Te) and BY (Y = P, As, Sb) metal-semiconductor (MS) contact are investigated via first principles calculations. Binding energies, mechanical properties, phonon spectra and ab initio molecular dynamics (AIMD) simulations confirm the stabilities of these systems. TaX2-BY (X = S, Se, Te; Y = P, As, Sb) MS van der Waals heterostructures (vdWHs) are found to be metal with a Schottky contact at the interface. Formation of the n-type Schottky contact at the interface of TaX2-BY (X = S, Se, Te; Y = P, As, Sb) MS vdWHs favors electron conduction over hole conduction. Small (higher) effective mass (carrier mobility) make TaS2-BSb, TaSe2-BSb and TaTe2-BSb MS vdWHs, potential candidates for high speed nanoelectronic applications. Bader charge analysis shows that at the interface of TaX2-BY (X = S, Se, Te; Y = P, As, Sb) MS vdWHs, in TaX2 (BP, BAs) the electrons transfer from the TaX2 layer to the BP and BAs layer, while in TaX2 (BSb) the electrons transfer from the BSb layer to TaX2 layer.