The use of metal and semimetal van der Waals contacts for 2D semiconducting devices has led to remarkable device optimizations. In comparison with conventional thin-film metal deposition, a reduction in Fermi level pinning at the contact interface for van der Waals contacts results in, generally, lower contact resistances and higher mobilities. Van der Waals contacts also lead to Schottky barriers that follow the Schottky–Mott rule, allowing barrier estimates on material properties alone. In this study, we present a double Schottky barrier model and apply it to a barrier tunable all van der Waals transistor. In a molybdenum disulfide (MoS2) 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
An analysis of the optoelectronic properties and photocurrent generation mechanisms in 2D multilayer crystallites of black phosphorus (BP) is conducted from 350 K down to cryogenic temperatures
- PAR ID:
- 10286509
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- physica status solidi (a)
- Volume:
- 218
- Issue:
- 20
- ISSN:
- 1862-6300
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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