Chemical vapor deposition of WS2/Mo1-xWxS2/MoS2 lateral heterostructures

The growth of lateral heterostructures of two-dimensional (2D) transition metal chalcogenides (TMDCs) opens up new paths for promising electronic and optoelectronic devices. Here, we demonstrate the one-step growth of 2D WS2/Mo1-xWxS2/MoS2 lateral heterostructures prepared on Si substrates by chemical vapor deposition (CVD), and the growth mechanism of WS2/Mo1-xWxS2/MoS2 lateral heterostructures are also systematically analyzed. The variation of radial Raman and photoluminescence (PL) spectrum of crystals on Si substrates are attributed to the three different structures of WS2, Mo1-xWxS2 and MoS2. Clear structure and optical modulation can be observed by Raman and PL mapping to further confirm the formation WS2/Mo1-xWxS2/MoS2 lateral heterostructures. According to the analysis of the optical properties and growth mechanism of the WS2/Mo1-xWxS2/MoS2 lateral heterostructures, it can be concluded that the formation of the lateral heterostructures depends on the growth temperature and chronology.