Journal
IEEE TRANSACTIONS ON ELECTRON DEVICES
Volume 65, Issue 10, Pages 4635-4640Publisher
IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
DOI: 10.1109/TED.2018.2863750
Keywords
2-D semiconductors; transition metal dichalcogenides
Funding
- imec's Industrial Affiliation Program
Ask authors/readers for more resources
2-D material FETs hold the promise of excellent gate control, but the impact of nonidealities on their performance remains poorly understood. This is because of the need, so far, to use computationally intensive nonequilibrium Green'sf unction (NEGF) simulations. Here, we therefore use a semiclassical model to investigate the role of nonidealities in the scaling of back-gated (BG) and top-gated (TG) monolayer MoS2 FETs. We verify the electrostatics and transport of the semiclassical model with density functional theory-based NEGF simulations and calibrate nonidealities, such as interface traps (D-it) and Schottky contact barrier height (OBB) to experimental monolayer and bilayer MoS2 FETs. We find that among the nonidealities, A t has the strongest subthreshold swing impact with 70 mV/dec obtainable in BG devices for a D-it of 5 x 10(11) cm(-2) eV(-1), an equivalent oxide thickness (EOT) of 1 nm, and a channel length (L-ch) of 5 nm. For scaled EOT, phi(SB) only strongly impacts I-ON for the TG case, as the overlapping gate thins the Schottky barriers in the BG case. We show in TG devices that a spacer of only 5 nm results in a 1000-fold drop in I-ON because of the nonidealities. We propose positive spacer oxide charge as a solution and show that a charge density of above 10(13) m(-2) is required to fully recover the device performance.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available