posted on 2019-12-23, 15:03authored byYibo Dong, Sheng Guo, Huahai Mao, Chen Xu, Yiyang Xie, Jun Deng, Le Wang, Zaifa Du, Fangzhu Xiong, Jie Sun
A technique for the in situ growth of patterned graphene
by CVD has been achieved directly on insulating substrates at 800
°C. The graphene growth is catalyzed by a Ni–Cu alloy
sacrificial layer, which integrates many advantages such as being
lithography-free, and almost wrinkle-free, with a high repeatability
and rapid growth. The etching method of the metal sacrificial layer
is the core of this technique, and the mechanism is analyzed. Graphene
has been found to play an important role in accelerating etching speeds.
The Ni–Cu alloy exhibits a high catalytic activity, and thus,
high-quality graphene can be obtained at a lower temperature. Moreover,
the Ni–Cu layer accommodates a limited amount of carbon atoms,
which ensures a high monolayer ratio of the graphene. The carbon solid
solubility of the alloy is calculated theoretically and used to explain
the experimental findings. The method is compatible with the current
semiconductor process and is conducive to the industrialization of
graphene devices.