title: Controlled charge trapping by molybdenum disulphide and graphene in ultrathin heterostructured memory devices.
abstract: Atomically thin two-dimensional materials have emerged as promising candidates for flexible and transparent electronic applications. Here we show non-volatile memory devices, based on field-effect transistors with large hysteresis, consisting entirely of stacked two-dimensional materials. Graphene and molybdenum disulphide were employed as both channel and charge-trapping layers, whereas hexagonal boron nitride was used as a tunnel barrier. In these ultrathin heterostructured memory devices, the atomically thin molybdenum disulphide or graphene-trapping layer stores charge tunnelled through hexagonal boron nitride, serving as a floating gate to control the charge transport in the graphene or molybdenum disulphide channel. By varying the thicknesses of two-dimensional materials and modifying the stacking order, the hysteresis and conductance polarity of the field-effect transistor can be controlled. These devices show high mobility, high on/off current ratio, large memory window and stable retention, providing a promising route towards flexible and transparent memory devices utilizing atomically thin two-dimensional materials.
authors.affiliation: Samsung-SKKU Graphene Center (SSGC), Sungkyunkwan University, Jangan-gu, Suwon, Gyeonggi-do 440-746, Korea.
authors.forename: Min Sup
authors.initials: MS
authors.lastname: Choi
authors.forename: Gwan-Hyoung
authors.initials: GH
authors.lastname: Lee
authors.forename: Young-Jun
authors.initials: YJ
authors.lastname: Yu
authors.forename: Dae-Yeong
authors.initials: DY
authors.lastname: Lee
authors.forename: Seung Hwan
authors.initials: SH
authors.lastname: Lee
authors.forename: Philip
authors.initials: P
authors.lastname: Kim
authors.forename: James
authors.initials: J
authors.lastname: Hone
authors.forename: Won Jong
authors.initials: WJ
authors.lastname: Yoo
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