Alkali-Assisted MOCVD Growth of Polycrystalline MoS2 with Micrometer-Scale Domains on Soda-Lime Glass

Achieving large-scale, uniform MoS2 films with reduced grain boundary density remains a central challenge for scalable device applications. Previous studies have reported that alkali-assisted growth promotes lateral domain expansion through eutectic intermediate formation. Here, metal–organic chemical vapor deposition (MOCVD) of MoS2 on commercial soda-lime glass is investigated. The intrinsic alkali content of soda-lime glass provides a uniform supply across the substrate, while partial surface softening at growth temperature facilitates the incorporation of Mo species within the near-surface region of the glass. The systematic variation of precursor flow conditions enables controlled modulation of nucleation density and domain size while suppressing graphitic carbon co-deposition arising from precursor ligand pyrolysis. High-quality polycrystalline MoS2 with lateral grain sizes ranging from ∼500 nm to 1.5 μm is achieved as uniform, coalesced centimeter-scale films, demonstrating the scalability of this method. Substrate roughness and wafer-to-wafer variability are key factors governing nucleation, highlighting opportunities for substrate optimization. To correlate the material properties with device performance, the films are wet-transferred and integrated into bottom-gated, top-contact field-effect transistors featuring either non-interdigitated or interdigitated source-drain electrodes. The devices exhibit on/off current ratios up to ∼107 and mobilities of ∼8 cm2 V–1 s–1. Overall, this work demonstrates an accessible and scalable route for the growth of electronic-grade polycrystalline MoS2 on soda-lime glass substrates.