[2Hp01-09] Low-dimensional Material/Nanostructure/Nanomaterial (LD/NS/NM)

[2Hp03] Fabrication and characterization of heterostructural WS₂/MoS₂ thin films with chemical vapor deposition

*Hiroki Waizumi¹, Tetsuo Shimizu¹, Atsushi Ando¹, Toshitaka Kubo¹ (1. National Institute of Advanced Industrial Science and Technology (AIST))

Various kinds of two-dimensional transition metal dichalcogenides (TMDCs) have been investigated for the application of electronical and optical thin film devices. In this report, we will discuss the structure and properties of heterostructural WS₂/MoS₂ thin films grown in-plane by chemical vapor deposition (CVD). We obtained "infinite-symbol-type" a thin film and noted the color difference between the center and the outer. In order to investigate this reason and its optical properties, we performed Raman and PL spectroscopy. Raman mapping from the peak intensities of WS₂ 2LA(M) and MoS₂ E¹_2g confirmed that the main component in the center is WS₂ and the outer is MoS₂. In addition, the intensity of the mapping peaks decreased near the boundaries, which suggests that distortion caused by lattice mismatch. Furthermore, Raman and PL spectra observed at two points, the center and the outer, showed clear difference, which conforms WS₂/MoS₂ with a precious in-plane heterostructure.