Graphene and 2-Dimensional Materials for Nanoelectronics Applications
The talk will focus on graphene-based hot electron transistors (Graphene Base Transistors, GBTs) for analog radio frequency applications , . The operating principle of GBTs is based on vertical current flow by quantum mechanical tunneling through an insulating barrier (Figure 1). The current (red arrow) can be controlled over several orders of magnitude by a base electrode made of graphene (Figure 2). The advantage of graphene over a metal base electrode is its ultimate thinness while maintaining good conductivity. If the barrier materials are optimized, GBTs have the potential to reach cut off frequencies (fT) on the order of 1 THz .
In the second part of the talk, options for optoelectronic devices based on 2D materials will be discussed. These include photodetectors / phototransistors made from graphene , where the photoresponse can be tuned by the voltage applied to a gate. In addition, photodiodes based on MoS2/silicon heterojunctions will be discussed.
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