Direct Formation of Wafer Scale Graphene Thin Layers on Insulating Substrates by Chemical Vapor Deposition

Abstract

Direct formation of high-quality and wafer scale graphene thin layers on insulating gate dielectrics such as SiO(2) is emergent for graphene electronics using Si-wafer compatible fabrication. Here, we report that in a chemical vapor deposition process the carbon species dissociated on Cu surfaces not only result in graphene layers on top of the catalytic Cu thin films but also diffuse through Cu grain boundaries to the interface between Cu and underlying dielectrics. Optimization of the process parameters leads to a continuous and large-area graphene thin layers directly formed on top of the dielectrics. The bottom-gated transistor characteristics for the graphene films have shown quite comparable carrier mobility compared to the top-layer graphene. The proposed method allows us to achieve wafer-sized graphene on versatile insulating substrates without the need of graphene transfer.

Improvement of Electrical Device Performances for Graphene Directly Grown on a SiO₂Substrate by Plasma Chemical Vapor Deposition

“…This is because of the hole doping of graphene from the SiO 2 substrate due to the naturally strong interaction tendencies between graphene and SiO 2 . This strong doping of graphene directly grown on SiO 2 is consistent with the results stated in our previous report [10] and those reported by another group [7]. Forward and reverse I ds -V gs curves are shown in Fig.…”

“…Based four-point probe measurements, sheet resistance of the fabricated graphene was found to be about 170 -200 Ω/sq (Fig. 3 (b)), a value much lower than that of graphene directly grown on SiO 2 substrate by thermal CVD (∼2000 Ω/sq) [7][8][9]. It was revealed that the hexagonal domain graphene with relatively large domain size (> 10 µm) was directly grown on the SiO 2 substrate by our method [10].…”

“…During this transfer, a lot of defects and impurities are introduced into graphene, which results in poor device performance. Direct growth of graphene on an insulating substrate is another approach for the fabrication of graphenebased electrical devices, and various investigations in this regard have been carried across the world [7][8][9][10]. Since the direct growth of graphene on an insulating substrate does not require any transfer process, better performance of the graphene-based device can be expected as compared with that of the graphene-based device fabricated via the transfer process.…”

Booming Development of Group IV–VI Semiconductors: Fresh Blood of 2D Family

“…CVD‐grown graphene has made great breakthrough in the growth of large‐area graphene 17, 155, 156, 157, 158, 159, 160. Recently, the synthesis of 2DLMs via CVD methods has been illustrated in many reports especially for MoS 2 ,30, 31, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185 which also shows promising applications in electronics and optoelectronics.…”

Graphene growth by transfer-free chemical vapour deposition on a cobalt layer

“…Electrical parameters were not measured in either of the two, cited works. A very interesting transfer-free method was used in [9]. The basic structure was Cu (300 nm)/SiO 2 / Si.…”