The effects of tensile strain and contact transmissivity on the performance limits of monolayer molybdenum disulfide ( MoS 2) nanoscale n-channel MOSFETs are studied using a semi-classical Monte Carlo method. Density functional theory calculations were performed to parametrize the electronic band structure of MoS 2 subject to tensile and shear strain. Tensile strain decreases the bandgap, increases the inter-valley band-edge energy separation between the light-mass K-valleys and heavier-mass Q-valleys, and decreases the K-valley effective mass in a way that depends on the direction and the amount of the applied strain. Biaxial tensile strain and uniaxial tensile strain along the x- or y-directions are found to have the largest effect. In bulk materials, low-field phonon-limited electron mobility is enhanced, peak and saturation drift velocities are increased, and high-field negative differential resistance becomes more pronounced. Both 200 and 15 nm gate length MoS 2 MOSFETs with end-contacts with ideal (unity) and more realistic (significantly sub-unity) contact interface transmissivity were simulated. These MoS 2 devices exhibited substantial sensitivity to strain with ideal contact transmissivity, and more so for the 15 nm quasi-ballistic device scale than 200 nm long-channel devices. However, the results showed much less strain sensitivity for devices with more realistic contact transmissivities, which may be good or bad depending on whether strain-insensitive or strain-sensitive performance is desired for a particular application and may be possible to modify with improved contact geometries.

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