A pioneering patent for free-floating graphene production technology

(Nanowerk News) A novel process for producing single layer graphene sheets has been invented by CRR’s chief scientist, Larry Fullerton. Cedar Ridge Research (CRR) has received U.S. patent 9,334,168 from the United States Patent and Trademark Office (USPTO) for the process. It leverages the diamagnetism properties of graphene to synthesize defect-free monolayer graphene as a free-floating structure. The new patent is CRR’s third patent for its free-floating graphene production technology to be issued by the USPTO since May of 2014 and the second to issue within the last six months.
CRR’s process for generating a floating continuous graphene film builds upon the traditional chemical vapor deposition (CVD) method. The process involves generating an even plasma distribution to produce a glow discharge of ionized carbon atoms at a desired rate that controls the continuous growth of a graphene film suspended over an alternating polarity magnetic structure having a sufficient gradient to float graphene in a stable manner. The free-floating growth process requires virtually no raw materials or surface preparation and eliminates the metal etching and transfer issues that lead to atomic-scale flaws that reduce efficiency. Graphene film produced using this process can be free of undulations, grain boundaries or defects that may cause uneven build-up of the graphene into a polycrystalline structure.
The process also enables processing of the graphene during its production including using lasers to draw conductive circuit board traces, applying other atoms using stereo lithography to build nanostructures, and activating carbon and mixing impurities to produce semiconductors.
“Our initial investigations have demonstrated an effective technique to economically produce high quality commercial scale graphene without the use of any growth substrate simply by utilizing the interplay between a magnetic field and the diamagnetic nature of graphene. This permits the growth of pristine defect-free films and alleviates the need to remove a film from a substrate after it has grown to its desired size and shape,” said Larry Fullerton.
CRR’s free-floating graphene production technology has the potential for substantially increasing the rate of graphene adoption by enabling volume production of high quality graphene sheets as well as graphene sheets tailored to meet specific application requirements.
CRR President Mark Roberts said, "We are very excited about receiving this pioneer patent for our free-floating graphene production technology. We believe it represents a fundamental capability to produce quality graphene sheets in a scalable and cost efficient manner that did not previously exist, and we fully expect that this technology will play a substantial role in the wide scale adoption of graphene as the next super material."
Source: Cedar Ridge Research