| 초록 |
In recent years there has been an explosive interest in research on two-dimensional (2-D) van der Waals (vdWs) materials due to their unique physical properties and great potential in the application of emerging devices. In aspect of device application, it is very important to achieve the directly grown single crystal on substrate with a large area, and many researchers have focused on the synthesis method and device characterization of the versatile vdWs materials with hexagonal symmetry such as graphene, h-BN and transition metal chalcogenide compounds. However, there are only a few reports on layered crystal of orthorhombic symmetry, which is another type of 2-D vdWs materials, and the 2-D growth on substrate has not been realized based on orthorhombic symmetry. Here, we show controlled polymorphic growth of 2D tin-sulfide crystals of either hexagonal SnS2 or orthorhombic SnS via control of the growth atmosphere and the growth behavior is supported by the thermodynamic study. Our layered crystals shows n-type for SnS2 and p-type characteristics for SnS, respectively. In addition to this, we demonstrate p-n heterojunction devices and feasibility of using the 2D crystals for thermoelectric devices. |
