Fig. 3: Wafer-scale growth of PtTe₂ patterns for synthetic edge contact arrays.

a Schematic of procedure for realizing PtTe₂-MoS₂ heterostructure arrays in a position-controllable manner, involving photolithography before the tellurization of Pt. b Photograph image of as-grown large-scale PtTe₂ patterns on a 2-inch-scale SiO₂/Si substrate (left), and representative OM images of the thin film captured on the left image (right). c Sheet resistance (R_sh) of as-grown PtTe₂ thin film as a function of the film thickness (H), characterized by four-probe method. R_sh values for high-quality PtTe₂ from previous reports^27,53 are displayed for comparison. The inset shows a representative AFM image of the as-grown thin film (scale bar: 1 μm). d (left) XPS-derived atomic ratio of the thin film, showing the nearly ideal stoichiometry of PtTe₂ (at. % (Te/Pt) ≈ 2; dashed red line) irrespective to T up to 825 °C, (right) R_sh of thin films as a function of annealing T, with R_sh ~467 Ω/sq (for T = 500 °C) indicated with a blue dashed line. e Representative OM images of MoS₂ monolayer laterally contacted to the edge of polycrystalline PtTe₂ thin film patterns with H ≈ 4 nm, in the form of fully stitched thin film depending on the growth conditions. f Representative Raman spectrum of PtTe₂-MoS₂ heterostructure, showing strong signals of each material, e.g., E_g (110.2 cm⁻¹) and A_1g (156.5 cm⁻¹) peaks of PtTe₂ and E_2g (384.5 cm⁻¹) and A_1g (402.3 cm⁻¹) modes of MoS₂. g, h TEM analysis of heterostructure with patterned PtTe₂ (H ≈ 4 nm) and monolayer MoS₂. g HAADF-STEM image of heterostructure showing epitaxially stitched PtTe₂ and MoS₂ without void-like defects along both surfaces. h Diffractogram corresponding to interface region, indicating orientationally aligned (100) and (110) planes in each atomic structure.