Epitaxial graphene homogeneity and quantum Hall effect in millimeter-scale devices

Published

April 1, 2017

Author(s)

Yanfei Yang, Guangjun Cheng, Chiashain Chuang, Angela R. Hight Walker, Randolph E. Elmquist, Irene G. Calizo, Randall M. Feenstra, Patrick Mende

Abstract

Quantized magnetotransport is observed in 5.6 × 5.6 mm2 epitaxial graphene devices, grown using highly constrained sublimation on the Si-face of SiC(0001) at high temperature (1900 °C). The precise quantized Hall resistance of Rxy = h/〖2e〗^2 is maintained up to record level of critical current Ixx = 0.72 mA at T = 3.1 K and 9 T in a device where Raman microscopy reveals low and homogeneous strain. Adsorption-induced molecular doping in a second device reduced the carrier concentration close to the Dirac point (n ≈ 1010 cm−2), where mobility of 18760 cm2/Vs is measured over an area of 10 mm2. Atomic force, confocal optical, and Raman microscopies are used to characterize the large-scale devices, and reveal improved SiC terrace topography and the structure of the graphene layer. Our results show that the structural uniformity of epitaxial graphene produced by face-to-graphite processing contributes to millimeter-scale transport homogeneity, and will prove useful for scientific and commercial applications.

Citation

Carbon

Volume

115

Pub Type

Journals

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Keywords

graphene, quantum Hall effect, resistance metrology, dissipation, homogeneity, Raman

Citation

Yang, Y. , Cheng, G. , Chuang, C. , Hight, A. , Elmquist, R. , Calizo, I. , Feenstra, R. and Mende, P. (2017), Epitaxial graphene homogeneity and quantum Hall effect in millimeter-scale devices, Carbon, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=918823 (Accessed December 13, 2024)