title: Exfoliation of large-area transition metal chalcogenide single layers.
abstract: Isolating large-areas of atomically thin transition metal chalcogenide crystals is an important but challenging task. The mechanical exfoliation technique can provide single layers of the highest structural quality, enabling to study their pristine properties and ultimate device performance. However, a major drawback of the technique is the low yield and small (typically < 10 μm) lateral size of the produced single layers. Here, we report a novel mechanical exfoliation technique, based on chemically enhanced adhesion, yielding MoS2 single layers with typical lateral sizes of several hundreds of microns. The idea is to exploit the chemical affinity of the sulfur atoms that can bind more strongly to a gold surface than the neighboring layers of the bulk MoS2 crystal. Moreover, we found that our exfoliation process is not specific to MoS2, but can be generally applied for various layered chalcogenides including selenites and tellurides, providing an easy access to large-area 2D crystals for the whole class of layered transition metal chalcogenides.
authors.affiliation: Centre for Energy Research, Institute of Technical Physics and Materials Science, 2D Nanoelectronics "Lendület" Research Group, Budapest, Hungary.
authors.forename: Gábor Zsolt
authors.initials: GZ
authors.lastname: Magda
authors.affiliation: Centre for Energy Research, Institute of Technical Physics and Materials Science, 2D Nanoelectronics "Lendület" Research Group, Budapest, Hungary.
authors.forename: János
authors.initials: J
authors.lastname: Pető
authors.affiliation: Centre for Energy Research, Institute of Technical Physics and Materials Science, 2D Nanoelectronics "Lendület" Research Group, Budapest, Hungary.
authors.forename: Gergely
authors.initials: G
authors.lastname: Dobrik
authors.affiliation: Korea Research Institute of Standards and Science, Center for Nanometrology, Daejeon, South Korea.
authors.forename: Chanyong
authors.initials: C
authors.lastname: Hwang
authors.affiliation: Centre for Energy Research, Institute of Technical Physics and Materials Science, Nanotechnology Department, Budapest, Hungary.
authors.forename: László P
authors.initials: LP
authors.lastname: Biró
authors.affiliation: Centre for Energy Research, Institute of Technical Physics and Materials Science, 2D Nanoelectronics "Lendület" Research Group, Budapest, Hungary.
authors.forename: Levente
authors.initials: L
authors.lastname: Tapasztó