▎ 摘　　要

Epitaxial graphene thin films were grown in an argon atmosphere by silicon sublimation from the (0001) faces of 4H-SiC in a temperature range T = 1520-1710 degrees C. Surface morphology, structure and the electrical properties of the layers were studied using atomic force microscopy (AFM), Auger electron spectroscopy (AES), and the measurements of Hall effect mobilities and sheet carrier densities. We further improved the computational model for the analysis of the AES in the determination of the number of graphene layers on SiC. A narrow temperature window T = 1620-1650 degrees C was found that clearly maximizes the Hall effect mobility up to 400 cm(2)/Vs in the cases where also a graphene monolayer is formed. The rather low values of the Hall effect mobilities are explained using a barrier model where regions having low resistivity are separated by higher resistivity barrier regions related to the observed grain boundaries in the graphene films. (C) 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim