Large scale graphene/h-BN heterostructures obtained by direct CVD growth of graphene using high-yield proximity-catalytic process

Hadi Arjmandi-Tash, Dipankar Kalita, Zheng Han, Riadh Othmen, Goutham Nayak, Cecile Berne, John Landers, Kenji Watanabe, Takashi Taniguchi, Laëtitia Marty, Johann Coraux, Nedjma Bendiab (+1 others)
2018 Journal of Physics: Materials  
We present a transfer-free process for the rapid growth of graphene on hexagonal boron nitride (h-BN) flakes via chemical vapor deposition. The growth of graphene on top of h-BN flakes is promoted by the adjacent copper catalyst. Full coverage of half-millimeter-sized h-BN crystals is demonstrated. The proximity of the copper catalyst ensures high-yield with a growth rate exceeding 2 μm min −1 , which is orders of magnitude above what was previously reported on h-BN and approaches the growth
more » ... aches the growth rate on copper. Optical and electron microscopies along with Raman mapping indicates a two-step growth mechanism, leading to the h-BN being first covered by discontinuous graphitic species prior to the formation of a continuous graphene layer. Electron transport measurements confirm the presence of well-crystallized and continuous graphene, which exhibits a charge carrier mobility that reaches 2.0×10 4 cm 2 V −1 s −1 . Direct comparison of the mobility with graphene/h-BN devices obtained by wet transfer confirms an enhanced charge neutrality for the in situ grown structures.
doi:10.1088/2515-7639/aac66e fatcat:kalhfjxttzfqbmpuy4tkn6yqle