2D semiconductors offer a promising platform for next-generation integrated circuits and large-scale electronic systems. Realizing high-performance p-type transistors, however, remains challenging due to Fermi-level pinning, high contact resistance, and poorly defined interfaces in conventional stepwise fabrication. Here, we demonstrate a single-step tellurization growth strategy that simultaneously forms PtTe2 contacts on 2H-MoTe2 channels to directly realize 2D semiconductor transistors. This approach forms PtTe2/2H-MoTe2 metal/semiconductor arrays with precise control of the MoTe2 phase at the PtTe2 electrode interface, while providing integrated van der Waals metallic contacts without the need for post-growth of metal contacts. Using this method, we achieve wafer-scale heterophase arrays characterized by uniform patterning and well-controlled 2H/1T' phase transformation dynamics. The heterojunctions display sharp and clean interfaces, as verified by TEM, STEM, and EDS mapping. Transistor arrays fabricated from these heterophase structures show Ohmic contacts with low Schottky barrier heights, delivering on/off ratios up to 5 × 104 and consistent mobility of 5-9 cm2/Vs across 100 devices, ensuring efficient carrier injection. Our results establish a scalable pathway for the direct growth of 2D semiconductor transistors, overcoming conventional multi-step device fabrication bottlenecks and providing a promising platform for large-scale, and reproducible 2D electronics.
Shuai et al. (Sat,) studied this question.