Date Published: May 19, 2017
Publisher: John Wiley and Sons Inc.
Author(s): Guangyuan Lu, Tianru Wu, Peng Yang, Yingchao Yang, Zehua Jin, Weibing Chen, Shuai Jia, Haomin Wang, Guanhua Zhang, Julong Sun, Pulickel M. Ajayan, Jun Lou, Xiaoming Xie, Mianheng Jiang.
Graphene/hexagonal boron nitride (h‐BN) monolayer in‐plane heterostructure offers a novel material platform for both fundamental research and device applications. To obtain such a heterostructure in high quality via controllable synthetic approaches is still challenging. In this work, in‐plane epitaxy of graphene/h‐BN heterostructure is demonstrated on Cu–Ni substrates. The introduction of nickel to copper substrate not only enhances the capability of decomposing polyaminoborane residues but also promotes graphene growth via isothermal segregation. On the alloy surface partially covered by h‐BN, graphene is found to nucleate at the corners of the as‐formed h‐BN grains, and the high growth rate for graphene minimizes the damage of graphene‐growth process on h‐BN lattice. As a result, high‐quality graphene/h‐BN in‐plane heterostructure with epitaxial relationship can be formed, which is supported by extensive characterizations. Photodetector device applications are demonstrated based on the in‐plane heterostructure. The success will have important impact on future research and applications based on this unique material platform.
Growth: Cu–Ni alloy foils containing 15 atom% Ni (Cu85Ni15) were used as substrates, and time dependence of experimental parameters is given in Figure S1 (Supporting Information). Details of the substrate preparation and h‐BN growth were described in our earlier report.22 As h‐BN growth ended, the substrates were first maintained at 1050 °C for 10 min in an H2 flow at a low pressure to make sure that the borazane precursor was completely cooled down. Then an H2/CH4 (100/50 sccm) mixture were introduced for graphene growth. After that, the substrates cooled down to room temperature in a mixed Ar/H2 flow.
The authors declare no conflict of interest.