Ultra-clean high-mobility graphene on technologically relevant substrates

Abstract

2-step chemical cleaning allows enhanced removal of polymeric residues from the surface of graphene, leading to significantly improved electrical and morphological properties.

Magnetic and Electric Field Dependent Charge Transfer in Perovskite/Graphene Field Effect Transistors

“…Materials: Ultra-clean high-mobility (µ ∼ 10000 cm 2 V −1 s −1 at room temperature) CVD graphene on SiO 2 /Si substrate (285 nm of SiO 2 ) was produced at the National Enterprise for NanoScience and NanoTechnology (NEST, Italy). [47] Pristine graphene/SiO 2 /Si wafers were processed into multi-terminal Hall bars and two-terminal diodes. The processing technique can be used to fabricate weakly n-and p-type graphene field-effect transistors (GFETs) with Dirac point close to zero gate voltage, |V g | < 20 V (Figure 1).…”

Atomically resolved electronic properties in single layer graphene on α-Al2O3 (0001) by chemical vapor deposition

“…To fully exploit the exceptional properties of 2DMs for new neuromorphic computing concepts, a scalable process compatible with semiconductor technology is needed to obtain high-quality material on technologically relevant wafer sizes 9 .Chemical vapor deposition (CVD) has proven to be a reliable, reproducible, and technologically viable synthesis route to wafer-scale SLG films characterised by good crystallinity, low impurity densities and full compatibility with large-scale back-end-of-line (BEOL) integration. Large-area SLG were initially fabricated by CVD on Cu, which serves as a catalyst for the decomposition of hydrocarbon sources [10][11][12][13] . However, impurities resulting from imperfect removal of metal catalysts and the PMMA (poly(methyl 2-methylpropenoate)), which is required for the transfer processes, hinder the use of this material for high-volume production while meeting semiconductor standards 14,15 .…”

Unexpected Electron Transport Suppression in a Heterostructured Graphene–MoS2Multiple Field-Effect Transistor Architecture

“…A clear trend is observed in the transfer characteristics: curves go from a conventional ambipolar behavior in Figure c to a limit of strongly quenched n-type conduction for the largest coverage in Figure g. The observation of a quenching of the field effect in graphene–TMD heterostructures has been reported in the literature, for instance in both WS 2 and MoS 2 –graphene heterostructures and in graphene functionalized with different materials, such as TiO 2 or organic molecules. ,,,− The important role of MoS 2 on electron transport suppression is clear as no deep suppression is observed in bare graphene stripes on SiO 2 devices . However, the observed behavior is somewhat puzzling since, ideally, MoS 2 should not affect carrier density in graphene when positioned on top of back-gated graphene due to the reciprocal screening in the vdW heterostructure …”

“…10,17,18,50−52 The important role of MoS 2 on electron transport suppression is clear as no deep suppression is observed in bare graphene stripes on SiO 2 devices. 53 However, the observed behavior is somewhat puzzling since, ideally, MoS 2 should not affect carrier density in graphene when positioned on top of back-gated graphene due to the reciprocal screening in the vdW heterostructure. 22 We ascribe the origin of this apparent discrepancy as due to vacancies in TMDs.…”