Conformal deposition of WS2 layered film by low-temperature metal-organic chemical vapor deposition

Large area multi-layer WS2 film has high potential as a channel material for MOSFETs in next-generation LSIs. State-of-the-art LSIs have complex three-dimensional (3D) structures such as vertical channels and multi-layer stacked channels surrounded by gate electrodes. To develop such structures, it is desirable to fabricate channel layers by CVD, which is suitable for conformal deposition along a substrate with a complicated 3D structure. In this study, we report on WS2 films deposited by Metal-Organic CVD using low-toxicity n-BuNC-W(CO)(5) as a liquid tungsten precursor and (t-C4H9)(2)S-2 for sulfur precursor. The deposited films have a roughly stoichiometric composition and are stable even after 60 d of shelf time in air atmosphere. A layered film along the 3D fin substrate parallel to the surface was fabricated on the entire structure.

Automated summary

Large area multi-layer WS2 film shows great potential as a channel material for MOSFETs in next-generation LSIs. To fabricate complex three-dimensional (3D) structures, it is desirable to use CVD to deposit channel layers along a substrate with a complicated 3D structure. In this study, WS2 films were deposited using Metal-Organic CVD and showed stable composition and structure even after 60 days of shelf time in air atmosphere.