On/off-current ratios of transfer-free bilayer graphene FETs as a function of temperature

In this paper we report on a novel method to fabricate graphene transistors directly on oxidized silicon wafers without the need to transfer graphene. By means of catalytic chemical vapor deposition (CCVD) the in-situ grown bilayer graphene transistors (BiLGFETs) are realized directly on oxidized silicon substrate. These BiLGFETs possess unipolar p-type device characteristics with an extremely high on/off-current ratio between 1×10⁶ and 1×10⁷ at room temperature [1, 2], exceeding previously reported values by several orders of magnitude. Furthermore, when increasing the ambient temperature to 200°C, the on/off-current ratio only degrades by one order of magnitude for BiLGFETs. Besides the excellent device characteristics, the complete CCVD fabrication process is silicon CMOS compatible. This will allow a simple and low-cost integration of graphene devices for nanoelectronic applications in a hybrid silicon CMOS environment.