Insulating SiO<sub>2</sub> under Centimeter-Scale, Single-Crystal Graphene Enables Electronic-Device Fabrication
Hui Guo, Xueyan Wang, Li Huang, Xin Jin, Zhenzhong Yang, Zhang Zhou, Hai Hu, Yuyang Zhang, Hongliang Lu, Qinghua Zhang, Chengmin Shen, Xiao Lin, Lin Gu, Qing Dai, Lihong Bao, Shixuan Du, Werner A. Hofer, Sokrates T. Pantelides, Hong‐Jun Gao
Abstract
Graphene on SiO2 enables fabrication of Si-technology-compatible devices, but a transfer of these devices from other substrates and direct growth have severe limitations due to a relatively small grain size or device-contamination. Here, we show an efficient, transfer-free way to integrate centimeter-scale, single-crystal graphene, of a quality suitable for electronic devices, on an insulating SiO2 film. Starting with single-crystal graphene grown epitaxially on Ru(0001), a SiO2 film is grown under the graphene by stepwise intercalation of silicon and oxygen. Thin (∼1 nm) crystalline or thicker (∼2 nm) amorphous SiO2 has been produced. The insulating nature of the thick amorphous SiO2 is verified by transport measurements. The device-quality of the corresponding graphene was confirmed by the observation of Shubnikov-de Haas oscillations, an integer quantum Hall effect, and a weak antilocalization effect within in situ fabricated Hall bar devices. This work provides a reliable platform for applications of large-scale, high-quality graphene in electronics.