▎ 摘　　要

Graphene was prepared by negative C-4 cluster ion implantation at 5 keV/atom followed by vacuum thermal annealing and cooling. The surface morphology and structure of samples were studied by scanning electron microscopy, atomic force microscopy, and Raman spectroscopy. Improvement of the graphene quality was realized by optimization of the post thermal processes. 1-2 layer graphene was obtained with I-2D/I-G ratio of 1.43 and I-D/I-G ratio of 0.07 at the implantation dose of 12 x 10(15) atoms/cm(2) and annealed at 900 degrees C followed by cooling at 20 degrees C/min. (C) 2013 Elsevier B.V. All rights reserved.