Graphene, with its hexagonal carbon network of atomic layers, has sparked a lot of interest in the scientific world as the first two-dimensional material to be isolated. Alfa Chemistry provides a bespoke graphene synthesis service that produces high-quality graphene thin films. CVD graphene thin films and plasma graphene thin films are among the products we offer.
CVD Graphene Thin Films
Alfa Chemistry can produce single atom thick graphene flakes on scales up to meters by chemical vapor deposition (CVD). For substrates that cannot tolerate the processing temperatures of CVD graphene synthesis, CVD graphene transfer can be used. We use a variety of ways to transfer CVD graphene sheets to various substrates.
Customers bring us their substrates to be transferred, and we apply the graphene monolayer on top of them using an innovative process. Graphene has been successfully transferred on a number of substrates, including gold, alumina, silver mirror, and sapphire. Contact us immediately to discuss your graphene film bespoke requirements!
Plasma Graphene Thin Films
The plasma process is now one of the most thoroughly explored methods for graphene production at Alfa Chemistry, with the advantages of lower temperatures and faster synthesis than conventional CVD procedures. In plasma-assisted synthesis, multiple topologies of graphene films can be obtained depending on the metal catalyst utilized.
- Due to its low cost, abundance, and low carbon solubility, copper (Cu) is the most often utilized catalyst for the production of 2D graphene films, promoting the development of monolayer graphene sheets. Because of this feature, graphene sheets made from Cu are intriguing candidates for high-mobility electrical applications. We used (ICP) PECVD to make 2D graphene sheets at 220 °C with a synthesis time of 2-4 minutes. The graphene on the plasma-treated copper substrate can also be removed by simply soaking the sample in water. This enables for chemical-free graphene transfer while removing the copper substrate.
- Nickel (Ni) is also commonly employed in graphene films production. Graphene films formed on Ni substrates using plasma techniques typically have multilayer architectures. Because of the differences in catalytic activity and carbon solubility, the production of graphene sheets on Ni substrates necessitates higher temperatures and shorter processing durations than on Cu substrates.
Fig 1. Low-temperature synthesis of 2D graphene films on Cu foil by ICP process with unique chemical-free, water-assisted transfer. (Zhao J. H, et al. 2018)
- In addition to this, Alfa Chemistry has made efforts to evaluate the feasibility of synthesizing graphene films in a plasma-assisted process using other metal or dielectric substrates, such as cobalt, glass, quartz, SiC, and SiO2.
- Our latest study has also focused on fabricating functional devices by manufacturing graphene films directly on substrates. Single-domain graphene films, for example, have been grown directly on h-BN using a PECVD technique at temperatures as low as 500 degrees. High-performance graphene-based FET devices can be made without the use of a transfer method.
Quality Control
To ensure high quality and reproducibility, all of our graphene thin film samples go through a rigorous quality control process. Class 1000 cleanrooms are used to process all of our graphene film materials. The following tests must be passed by each sample from each batch.
- Testing with Raman spectroscopy
- Optical microscopy is used to ensure the quality and purity of the transfer.
- Please contact us if your application necessitates more specialized controls such as AFM, SEM, and so on.
Contact us immediately to discuss your graphene film bespoke requirements!
Reference
- Zhao J. H, et al. (2018). "Recent Progress in Plasma-Assisted Synthesis and Modification of 2D Materials." 2D Mater. 5: 032002.
Please kindly note that our products are for research use only.
