Monolayer-MoS2 Stacked Nanosheet Channel with C-type Metal Contact

This work demonstrates the first stacked nanosheet devices with monolayer MoS
2
channel after successful simultaneous release of 2 nanosheets. Two-stacked monolayer MoS
2
nanosheets with 50-nm width can be released free up to 150 nm, proving excellent mechanical properties of the channel material. Conformal gate stack deposition on the 2-stacked MoS
2
sheets is confirmed. To increase contact area, we introduce here ‘C-type’ wrap-around contact that contacts not only the edge but also the top and bottom side on the monolayer MoS
2
channels. For the first time, studies of gate stack and its impact on subthreshold swing, threshold voltage and hysteresis are presented on single nanosheet gate all around (GAA) devices. Unlike most reports in literature of depletion-mode monolayer MoS
2
devices, through appropriate process control and interface engineering we report here positive threshold voltage for NMOS devices.