Rapid Wafer-Scale Growth of Polycrystalline 2H-MoS₂ by Pulsed Metal–Organic Chemical Vapor Deposition

Abstract

High-volume\nmanufacturing of devices based on transition metal\ndichalcogenide (TMD) ultrathin films will require deposition techniques\nthat are capable of reproducible wafer-scale growth with monolayer\ncontrol. To date, TMD growth efforts have largely relied upon sublimation\nand transport of solid precursors with minimal control over vapor-phase\nflux and gas-phase chemistry, which are critical for scaling up laboratory\nprocesses to manufacturing settings. To address these issues, we report\na new pulsed metal–organic chemical vapor deposition (MOCVD)\nroute for MoS₂ film growth\nin a research-grade single-wafer reactor. Using bis­(<i>tert</i>-butylimido)­bis­(dimethylamido)molybdenum and diethyl disulfide, we\ndeposit MoS₂ films from ∼1 nm to ∼25 nm in\nthickness on SiO₂/Si substrates. We show that layered 2H-MoS₂ can be produced at comparatively low reaction temperatures\nof 591 °C at short deposition times, approximately 90 s for few-layer\nfilms. In addition to the growth studies performed on SiO₂/Si, films with wafer-level uniformity are demonstrated on 50 mm\nquartz wafers. Process chemistry and impurity incorporation from precursors\nare also discussed. This low-temperature and fast process highlights\nthe opportunities presented by metal–organic reagents in the\ncontrolled synthesis of TMDs.