title: Long-Term Stability and Reliability of Black Phosphorus Field-Effect Transistors.
abstract: Black phosphorus has been recently suggested as a very promising material for use in 2D field-effect transistors. However, due to its poor stability under ambient conditions, this material has not yet received as much attention as for instance MoS2. We show that the recently demonstrated Al2O3encapsulation leads to highly stable devices. In particular, we report our long-term study on highly stable black phosphorus field-effect transistors, which show stable device characteristics for at least eight months. This high stability allows us to perform a detailed analysis of their reliability with respect to hysteresis as well as the arguably most important reliability issue in silicon technologies, the bias-temperature instability. We find that the hysteresis in these transistors depends strongly on the sweep rate and temperature. Moreover, the hysteresis dynamics in our devices are reproducible over a long time, which underlines their high reliability. Also, by using detailed physical models for oxide traps developed for Si technologies, we are able to capture the channel electrostatics of the black phosphorus FETs and determine the position of the defect energy band. Finally, we demonstrate that both hysteresis and bias-temperature instabilities are due to thermally activated charge trapping/detrapping by oxide traps and can be reduced if the device is covered by Teflon-AF.
authors.affiliation: Institute for Microelectronics (TU Wien) , Gusshausstrasse 27-29, 1040 Vienna, Austria.|Ioffe Physical-Technical Institute , Polytechnicheskaya 26, 194021 St-Petersburg, Russia.
authors.forename: Yury Yuryevich
authors.initials: YY
authors.lastname: Illarionov
authors.affiliation: Institute for Microelectronics (TU Wien) , Gusshausstrasse 27-29, 1040 Vienna, Austria.
authors.forename: Michael
authors.initials: M
authors.lastname: Waltl
authors.affiliation: Institute for Microelectronics (TU Wien) , Gusshausstrasse 27-29, 1040 Vienna, Austria.
authors.forename: Gerhard
authors.initials: G
authors.lastname: Rzepa
authors.affiliation: The University of Texas at Austin , 10100 Burnet Road 160, Austin, Texas 78758, United States.
authors.forename: Joon-Seok
authors.initials: JS
authors.lastname: Kim
authors.affiliation: The University of Texas at Austin , 10100 Burnet Road 160, Austin, Texas 78758, United States.
authors.forename: Seohee
authors.initials: S
authors.lastname: Kim
authors.affiliation: The University of Texas at Austin , 10100 Burnet Road 160, Austin, Texas 78758, United States.
authors.forename: Ananth
authors.initials: A
authors.lastname: Dodabalapur
authors.affiliation: The University of Texas at Austin , 10100 Burnet Road 160, Austin, Texas 78758, United States.
authors.forename: Deji
authors.initials: D
authors.lastname: Akinwande
authors.affiliation: Institute for Microelectronics (TU Wien) , Gusshausstrasse 27-29, 1040 Vienna, Austria.
authors.forename: Tibor
authors.initials: T
authors.lastname: Grasser
keywords: bias-temperature instabilities; hysteresis; oxide defects; phosphorene; stability of black phosphorus; transistor