title: Few-layer black phosphorus field-effect transistors with reduced current fluctuation.
abstract: We investigated the reduction of current fluctuations in few-layer black phosphorus (BP) field-effect transistors resulting from Al2O3 passivation. In order to verify the effect of Al2O3 passivation on device characteristics, measurements and analyses were conducted on thermally annealed devices before and after the passivation. More specifically, static and low-frequency noise analyses were used in monitoring the charge transport characteristics in the devices. The carrier number fluctuation (CNF) model, which is related to the charge trapping/detrapping process near the interface between the channel and gate dielectric, was employed to describe the current fluctuation phenomena. Noise reduction due to the Al2O3 passivation was expressed in terms of the reduced interface trap density values D(it) and N(it), extracted from the subthreshold slope (SS) and the CNF model, respectively. The deviations between the interface trap density values extracted using the SS value and CNF model are elucidated in terms of the role of the Schottky barrier between the few-layer BP and metal contact. Furthermore, the preservation of the Al2O3-passivated few-layer BP flakes in ambient air for two months was confirmed by identical Raman spectra.
authors.affiliation: Interface Control Research Center, Future Convergence Research Division, Korea Institute of Science and Technology , Seoul 136-791, South Korea .
authors.forename: Junhong
authors.initials: J
authors.lastname: Na
authors.forename: Young Tack
authors.initials: YT
authors.lastname: Lee
authors.forename: Jung Ah
authors.initials: JA
authors.lastname: Lim
authors.forename: Do Kyung
authors.initials: DK
authors.lastname: Hwang
authors.forename: Gyu-Tae
authors.initials: GT
authors.lastname: Kim
authors.forename: Won Kook
authors.initials: WK
authors.lastname: Choi
authors.forename: Yong-Won
authors.initials: YW
authors.lastname: Song
keywords: Al2O3; black phosphorus; low-frequency noise; passivation; phosphorene