▎ 摘　　要

Low-layered, transparent graphene is accessible by a chemical vapor deposition (CVD) technique on a Ni-catalyst layer, which is deposited on a < 100 > silicon substrate. The number of graphene layers on the substrate is controlled by the grain boundaries in the Ni-catalyst layer and can be studied by micro Raman analysis. Electrical studies showed a sheet resistance (Rsheet) of approximately 1435 Omega per square, a contact resistance (Rc) of about 127 Omega, and a specific contact resistance (R-sc) of approximately 2.8x10(-4) Omega cm(2) for the CVD graphene samples. Transistor output characteristics for the graphene sample demonstrated linear current/voltage behavior. A current versus voltage (IdsVds) plot clearly indicates a p-conducting characteristic of the synthesized graphene. Gas-sensor measurements revealed a high sensor activity of the low-layer graphene material towards H-2 and CO. At 300 degrees C, a sensor response of approximately 29 towards low H-2 concentrations (1 vol%) was observed, which is by a factor of four higher than recently reported.