▎ 摘　　要

Graphene with varying number of layers is explored as metal gate electrode in metal oxide semiconductor structure by inserting it between the dielectric (SiO2) and contact metal (TiN) and results are compared with TiN gate electrode. We demonstrate an effective work function tuning of gate electrode upto 0.5 eV by varying the number of graphene layers. Inclusion of even 1-3 layers of graphene results in significantly improved dielectric reliability as measured by breakdown characteristics, charge to breakdown, and interface state density. These improvements are attributed to the impermeability of graphene for TiN and hence reduced metallic contamination in the dielectric. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4726284]