In situ optical microscopy on LMCats
Maciej Jankowski 1, Gilles Renaud 2
CEA / Institute for Nanoscience and Cryogenics, Grenoble, France
The current approach to graphene (Gr) synthesis generally relies on CVD growth on solid substrates, mainly copper. Despite recent progress and fine-tuning of growth procedures there are significant obstacles in the production of large-scale and defect free graphene single-crystals. The main hurdle is a lack of knowledge about exact growth dynamics of Gr during CVD process. The current state-of-art methods, like electron microscopy, are limited in resolving in situ and real-time growth dynamics due to the prevailing conditions - high pressure and temperature- in CVD reactors. The problem is even worst in the case of liquid metals because of their high evaporation rate.
In this contribution we will present the experimental results of Gr growth on liquid copper in the LMCat CVD reactor. Using optical methods, we were capable to resolve in real-time the growth dynamics of graphene on liquid copper. A myriad of interesting growth scenarios was observed which allowed to fine-tune the elaboration procedures and to identify key factors impacting the growth of individual flakes, their self-assembly, and further association into a single layer with a coherent atomic structure.