A back-to-back diode model applied to MoS2 van der Waals Schottky diodes

Abstract

The use of metal van der Waals contacts and the implicit reduction in Fermi-level pinning in contacted semiconductors has led to remarkable device optimizations. For example, using graphene as an electrical contact allows for tunable Schottky barriers in transistors and barristors. In this study, we present a double Schottky barrier model and apply it to barrier tunable all van der Waals transistors. In a molybdenum disulfide (MoS${}_2$) transistor with graphene and few-layer graphene contacts, we find that the model can be applied to extract Schottky barrier heights that agree with the Schottky-Mott rule from simple two-terminal current-voltage measurements at room temperature. Furthermore, we show tunability of the Schottky barrier \textit{in-situ} using a regional contact gate. Our results show that a basic back-to-back diode model, applied to two terminal measurements, can capture the diode properties of all-van-der-Waals transistors relatively well.

arXiv comment6 pages, 3 figures

References in corpus (9)

• Tuning the graphene work function by electric field effect
• Van der Waals metal-semiconductor junction: weak Fermi level pinning enables effective tuning of Schottky barrier
• Atomically-thin Ohmic Edge Contacts Between Two-dimensional Materials
• Contact Engineering High Performance n-Type MoTe2 Transistors
• Doping Mechanisms in Graphene-MoS2 Hybrids
• InSe Schottky diodes based on van der Waals contacts
• Accurate Extraction of Schottky Barrier Height and Universality of Fermi Level De-pinning of van der Waals Contacts
• Modulation of Schottky barrier height in graphene/MoS2/metal vertical heterostructure with large current ON-OFF ratio
• Schottky barrier lowering due to interface states in 2D heterophase devices