Vertical Graphene-Based Transistors for Power Electronics, Optoelectronics and Radio-Frequency Applications

The combination of two-dimensional materials, such as graphene, with established thin films offers great opportunities for enabling next-generation vertical transistors for various applications. This paper gives a brief overview about different vertical transistor concepts using two-dimensional materials proposed so far, e.g. the hot electron transistor and the Barristor. With the arrival of two-dimensional materials, the hot electron transistor also experienced a revival with predicted cut-off frequencies in the THz range. The Barristor overcomes the weak current saturation of lateral graphene field-effect transistors and high on-off ratios up to 10 ⁷ were demonstrated, which are suitable parameters for logic applications. By combining a semiconductor-graphene-semiconductor design of the simplest hot electron transistor with the Barristor operating principle a new device, called graphene adjustable-barriers transistor, can be realized. This new device concept provides the potential for RF, power electronics, and optoelectronic applications.