Wafer‐Scale Epitaxial 1T′, 1T′–2H Mixed, and 2H Phases MoTe2 Thin Films Grown by Metal–Organic Chemical Vapor Deposition

Abstract

Abstract2D materials beyond molybdenum disulfide such as molybdenum ditelluride (MoTe2) have attracted increasing attention because of their distinctive properties, such as phase‐engineered, relatively narrow direct bandgap of 1.0–1.1 eV and superior carrier transport. However, a wafer‐scale synthesis process is required for achieving practical applications in next‐generation electronic devices using MoTe2 thin films. Herein, the direct growth of atomically thin 1T′, 1T′–2H mixed, and 2H phases MoTe2 films on a 4 in. SiO2/Si wafer with high spatial uniformity (≈96%) via metal–organic vapor phase deposition is reported. Furthermore, the wafer‐scale phase engineering of few‐layer MoTe2 film is investigated by controlling the H2 molar flow rate. While the use of a low H2 molar flow rate results in 1T′ and 1T′–2H mixed phase MoTe2 films, 2H phase MoTe2 films are obtained at a high H2 molar flow rate. Field‐effect transistors fabricated with the prepared 2H and 1T′ phases MoTe2 channels reveal p‐type semiconductor and semimetal properties, respectively. This work demonstrates the potential for reliable wafer‐scale production of 1T′ and 2H phases MoTe2 thin films employing the H2 molar flow rate‐controlled phase tunable method for practical applications in next‐generation electronic devices as a p‐type semiconductor and Wyle semimetal.