Gas-Source Chemical Vapor Deposition of Atomically Thin WS2 for LSI Device Applications

Growth behaviors of chemical vapor deposition (CVD) of WS
2
by using gaseous precursors of WF
6
and H
2
S will be presented. The WS
2
crystal growth exhibited layer-by-layer mode where nucleation and lateral growth were thermally activated. An optimized growth condition allowed us to obtain WS
2
crystal with a grain size larger than 3 µm, which is the largest size ever reported for gas-source CVD grown transition-metal dichalcogenides (TMDs) without an alkali-metal promotor.