Graphene has been considered as one of the potential post Si-materials due to its high mobility.  However, since graphene is semi-conductor with zero band gap, it is difficult to achieve high
Ion/Ioff ratio, one of the most important requirements for commercial devices. There have been many attempts to open its band gap for high
Ion/Ioff ratio, but most of them end up lowering the mobility. [2-5]
Thus, we proposed and demonstrated a new device structure for graphene transistor based on one of the unique properties of graphene for high
Ion/Ioff: using this approach, we were able to achieve the ratio over 105.
 Our device has several major advantages over previously proposed graphene based electronic devices. Since our device does not alter the given properties of graphene, such as opening the band gap, it has no fundamental issues on mobility degradations. In addition, our device is fully compatible with current Si technology and we were able to fabricate the devices with 6â? wafer scale with CVD (Chemical Vapor Deposition) grown graphene.
In this presentation, we will discuss about the details of our graphene device including the device structure and the detailed understanding of working mechanism. We will present device characteristics including I-V curves with 105 on/off ratio. We will also present the performance of an inverter based on our devices. Finally, we will discuss the current issues and their potential solutions.
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