Publication: Electron Transport across Vertical Silicon/MoS2/Graphene Heterostructures: Towards Efficient Emitter Diodes for Graphene Base Hot Electron Transistors

18/02/2020
  Left: Vertical MoS2-Graphene-Heterostructure, Right: Measurement curves

RWTH and AMO researchers demonstrate a thermionic-emission transport of electrons across Si/MoS2/Graphene structures for applications as emitter diodes in hot electron graphene base transistors (GBTs).

Researchers at the Chair of Electronic Devices at RWTH Aachen University and AMO GmbH in collaboration with Stanford University and IHP GmbH have investigated electron transport across Si/MoS2/Graphene vertical heterostructures that can make efficient emitter diodes of GBTs. The work is recently published in ACS applied materials and interfaces.

GBTs are three terminal devices comprised of two back-to-back connected diodes made of an emitter (n+-Si), base (graphene) and a collector (metal) separated by barrier layers. The first diode is the emitter diode that injects hot electrons while the second one is called the filtering diode as it enables only the high energy electrons to reach the collector. Enhancing the on-state collector current of GBTs, therefore, requires optimization of the emitter diode to promote Fowler-Nordheim or thermionic emission-based injection of hot electrons into the base across the emitter-base-barrier. This work demonstrates a thermionic emission-driven injection of hot electrons across Si/MoS2/Graphene vertical heterostructures that can be used as efficient emitter-diodes of GBTs for potential high-speed electronics.

The research work was funded by the European Commission (Graphene Flagship, 785219, QUEFORMAL, 829035) the German Ministry of Education and Research, BMBF (GIMMIK,03XP0210, NeuroTec, 16ES1134), and the German Research Foundation, DFG (MOSTFLEX, 407080863).