Chemical Vapor Deposition (CVD) graphene transfer processes are critical for the industrial application and scalability of graphene technology. However, the transfer of large-area CVD graphene films presents several challenges that need to be addressed to unlock the full potential of graphene for various industrial applications1,2.
Challenges in CVD Graphene Transfer
Batch Scale Limitations
Current transfer methods, such as oxidative decoupling and wet etch transfer, are often performed in batch processes. These methods are time-consuming and limit the scalability of the graphene transfer process3.
Obtaining largely contaminant-free CVD graphene is a significant challenge. The transfer process can introduce defects and tears on the graphene surface, affecting its quality4.
High Operating and Input Costs
The transfer process for CVD graphene can be costly due to the equipment, materials, and chemicals involved5.
Use of Harsh Chemicals
Some transfer methods require the use of harsh chemicals, which can be environmentally unfriendly and pose safety concerns6.
Successful Separation from the Substrate
While it is possible to create high-quality graphene on a substrate using CVD, successful “defect-free” separation of graphene from its growth substrate has been challenging.
Removing contaminants from transferred CVD graphene is a significant challenge. The complete removal of support materials without contaminating the graphene is crucial2.
Direct Growth on Insulating Substrates
Achieving direct growth on insulating substrates is a challenge in CVD graphene synthesis. This is important for expanding the range of potential applications for graphene3.
Transferring large-area graphene films with cleanliness and uniformity is another challenge. Both wet and dry transfer methods have their own advantages and challenges4.
Potential Solutions to CVD Graphene Transfer Challenges
Developing Roll-to-Roll Transfer Methods
Roll-to-roll transfer methods can potentially increase efficiency and scalability in CVD graphene transfer processes6.
Improving Transfer Techniques
Optimizing the transfer process parameters, such as temperature, pressure, and adhesion methods, can help minimize defects and tears on the graphene surface2.
Reducing Chemical-Intensive Processes
Finding alternative methods that reduce the reliance on harsh chemicals can make the transfer process more environmentally friendly3.
General Graphene’s Novel Approach to CVD Graphene Transfer
General Graphene has made significant advancements in both its roll-to-roll CVD graphene production and transfer technologies to directly address the challenges of producing mass volumes of CVD graphene films cost-effectively at reproducible qualities tailored for specific end applications3.
Towards the end of 2022, we integrated an inline coating system to GG 3.0, the third iteration of our proprietary roll-to-roll CVD production system. This integrated system enables us to coat a variety of thin polymer films onto a roll of CVD graphene-on-catalyst substrate. The thin polymer film coatings can also be cured and laminated before the resulting graphene-on-polymer output leaves the GG 3.0 production3.
The output is fed directly into our Roll-to-Roll CVD Graphene Transfer system, where the graphene-on-polymer is separated from the surface of the catalyst material. The system is capable of transferring several square meters of graphene onto a variety of polymeric films and has shown significant potential in helping facilitate large-area roll-to-roll transfers with minimal transfer induced defects3.
Additionally, this system has a very small chemical footprint which thereby makes it easier and less expensive to implement at scale. It can successfully reuse copper foil – its primary catalyst material – once the graphene-on-polymer has been separated from it3.
By addressing the challenges associated with traditional transfer processes and developing novel technology that directly addresses historical bottlenecks towards commercialization, General Graphene successfully demonstrates a path towards the industrial-scale manufacturing of large-area roll-to-roll CVD graphene films transferred to polymers.
References and further reading