TY - GEN A1 - Strobel, Carsten A1 - Alvarado Chavarin, Carlos A1 - Völkel, Sandra A1 - Jahn, Andreas A1 - Hiess, Andre A1 - Knaut, Martin A1 - Albert, Matthias A1 - Wenger, Christian A1 - Steinke, Olaff A1 - Stephan, Ulf A1 - Röhlecke, Sören A1 - Mikolajick, Thomas T1 - Enhanced Electrical Properties of Optimized Vertical Graphene-Base Hot Electron Transistors T2 - ACS Applied Electronic Materials N2 - The arrival of high-mobility two-dimensional materials like graphene leads to the renaissance of former vertical semiconductor–metal–semiconductor (SMS) hot electron transistors. Because of the monolayer thickness of graphene, improved SMS transistors with a semimetallic graphene-base electrode are now feasible for high-frequency applications. In this study we report about a device that consists of amorphous silicon, graphene, and crystalline silicon. For the first time, this device is fabricated by a four-mask lithography process which leads to significant improvements in the device performance. A strongly increased common-emitter current gain of 2% could be achieved while the on–off ratio improved to 1.6 × 105, which is already higher than predicted theoretically. This could be mainly attributed to better interface characteristics and decreased lateral dimensions of the devices. A cutoff frequency of approximately 26 MHz could be forecasted based on the DC measurements of the device. KW - Graphene KW - Transistor Y1 - 2023 U6 - https://doi.org/10.1021/acsaelm.2c01725 SN - 2637-6113 VL - 5 IS - 3 SP - 1670 EP - 1675 ER - TY - GEN A1 - Strobel, Carsten A1 - Alvarado Chavarin, Carlos A1 - Wenger, Christian A1 - Albert, Matthias A1 - Mikolajick, Thomas T1 - Vertical Graphene-Based Transistors for Power Electronics, Optoelectronics and Radio-Frequency Applications T2 - IEEE Nanotechnology Materials and Devices Conference (NMDC), Paestum, Italy, 22-25 October 2023 N2 - 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 twodimensional materials proposed so far, e.g. the hot electron transistor and the Barristor. With the arrival of twodimensional 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 107 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. KW - Graphene Y1 - 2023 SN - 979-8-3503-3546-0 SN - 979-8-3503-3547-7 U6 - https://doi.org/10.1109/NMDC57951.2023.10344102 SN - 2473-0718 SP - 196 EP - 201 PB - Institute of Electrical and Electronics Engineers (IEEE) ER -