Vertical Graphene Growth from Amorphous Carbon Films Using Oxidizing Gases

• Published in: Journal of physical chemistry. C 2015-08, Vol.119 (31), p.17965-17970
• Main Authors: Bachmatiuk, Alicja, Boeckl, John, Smith, Howard, Ibrahim, Imad, Gemming, Thomas, Oswald, Steffen, Kazmierczak, Wojciech, Makarov, Denys, Schmidt, Oliver G, Eckert, Juergen, Fu, Lei, Rummeli, Mark H
• Format: Article
• Language: English
• ISSN: 1932-7447; 1932-7455
• DOI: 10.1021/acs.jpcc.5b05167

Amorphous carbon thin films are technologically important materials that range in use from the semiconductor industry to corrosion-resistant films. Their conversion to crystalline graphene layers has long been pursued; however, typically this requires excessively high temperatures. Thus, crystallization routes which require reduced temperatures are important. Moreover, the ability to crystallize amorphous carbon at reduced temperatures without a catalyst could pave the way for practical graphene synthesis for device fabrication without the need for transfer or post-transfer gate deposition. To this end we demonstrate a practical and facile method to crystallize deposited amorphous carbon films to high quality graphene layers at reduced annealing temperatures by introducing oxidizing gases during the process. The reactive gases react with regions of higher strain (energy) in the system and accelerate the graphitization process by minimizing criss-cross-linkages and accelerating C–C bond rearrangement at defects. In other words, the movement of crystallite boundaries is accelerated along the carbon hexagon planes by removing obstacles for crystallite coalescence.