Halide vapor phase epitaxy of monolayer molybdenum diselenide single crystals
Taotao Li, Zhenping Chen, Liqi Zhou, Wenjie Sun, Weiyi Lin, Lei Liu, Xilu Zou, Si Gao, Yuefeng Nie, Yi Shi, Xinran Wang
Abstract
<p indent="0mm">Single-crystalline transition metal dichalcogenides (TMD) films are of potential application in future electronics and optoelectronics. In this work, a halide vapor phase epitaxy (HVPE) strategy was proposed and demonstrated for the epitaxy of molybdenum diselenide (MoSe<sub>2</sub>) single crystals, in which metal halide vapors were <italic>in-situ</italic> produced by the chlorination of molybdenum as sources for the TMD growth. Combined with the epitaxial sapphire substrate, unidirectional domain alignment was successfully achieved and monolayer single-crystal MoSe<sub>2</sub> films have been demonstrated on a 2-inch wafer for the first time. A series of characterizations ranging from centimeter to nanometer scales have been implemented to demonstrate the high quality and uniformity of the MoSe<sub>2</sub>. This work provides a universal strategy for the growth of TMD single-crystal films.