Spontaneous and self-oriented growth during chemical vapor epitaxy of single-crystalline MoS2

This research explores a novel approach to growing single-crystalline molybdenum disulfide (MoS2) without relying on sapphire template engineering. By carefully controlling the metal-organic precursor adsorption rate, the team observed spontaneous self-orientation of the MoS2 crystals, governed by the bulk sapphire crystallographic symmetry rather than the surface structure. This process also enables the annihilation of twin grain boundaries through van der Waals recrystallization, yielding high-quality, single-crystalline MoS2 monolayers. The team demonstrated this method at an industrial scale, achieving carrier mobilities up to 30 ± 5 cm2V−1s−1. This significant finding overcomes the stringent requirements of conventional epitaxy, paving the way for scalable production of high-quality 2D semiconductors.