Electrical characterization of top-gated molybdenum disulfide field-effect-transistors with high-k dielectrics

Autor: Robert M. Wallace, Chadwin D. Young, Pavel Bolshakov, Angelica Azcatl, Peng Zhao, Paul K. Hurley
Rok vydání: 2017
Předmět:
Zdroj: Microelectronic Engineering. 178:190-193
ISSN: 0167-9317
Popis: High quality HfO2 and Al2O3 substrates are fabricated in order to study their impact on top-gate MoS2 transistors. Compared with top-gate MoS2 FETs on a SiO2 substrate, the field effect mobility decreased for devices on HfO2 substrates but substantially increased for devices on Al2O3 substrates, possibly due to substrate surface roughness. A forming gas anneal is found to enhance device performance due to a reduction in charge trap density of the high-k substrates. The major improvements in device performance are ascribed to the forming gas anneal. Top-gate devices built upon Al2O3 substrates exhibit a near-ideal subthreshold swing (SS) of ~69mV/dec and a ~10 increase in field effect mobility, indicating a positive influence on top-gate device performance even without any backside bias. Display Omitted Top-gate MoS2 FETs were fabricated on high-k dielectric substrates.A forming gas anneal enhances device performance with a reduction in Dit.Top-gate devices on Al2O3/Si showed better performance than on HfO2/Si.AFM images suggest that substrate surface roughness affects device performance.
Databáze: OpenAIRE