Quantum confinement-induced semimetal-to-semiconductor evolution in large-area ultra-thin PtSe2 films grown at 400 °C
Open Access
- 3 September 2019
- journal article
- research article
- Published by Springer Science and Business Media LLC in npj 2D Materials and Applications
- Vol. 3 (1), 1-8
- https://doi.org/10.1038/s41699-019-0116-4
Abstract
In this work, we present a comprehensive theoretical and experimental study of quantum confinement in layered platinum diselenide (PtSe2) films as a function of film thickness. Our electrical measurements, in combination with density functional theory calculations, show distinct layer-dependent semimetal-to-semiconductor evolution in PtSe2 films, and highlight the importance of including van der Waals interactions, Green’s function calibration, and screened Coulomb interactions in the determination of the thickness-dependent PtSe2 energy gap. Large-area PtSe2 films of varying thickness (2.5–6.5 nm) were formed at 400 °C by thermally assisted conversion of ultra-thin platinum films on Si/SiO2 substrates. The PtSe2 films exhibit p-type semiconducting behavior with hole mobility values up to 13 cm2/V·s. Metal-oxide-semiconductor field-effect transistors have been fabricated using the grown PtSe2 films and a gate field-controlled switching performance with an ION/IOFF ratio of >230 has been measured at room temperature for a 2.5–3 nm PtSe2 film, while the ratio drops to 2 films, consistent with a semiconducting-to-semimetallic transition with increasing PtSe2 film thickness. These experimental observations indicate that the low-temperature growth of semimetallic or semiconducting PtSe2 could be integrated into the back-end-of-line of a silicon complementary metal-oxide-semiconductor process.Funding Information
- Irish Research Council (GOIPD/2016/643, GOIPD/2018/653)
- Science Foundation Ireland (15/SIRG/3329)
This publication has 45 references indexed in Scilit:
- Highly Sensitive Electromechanical Piezoresistive Pressure Sensors Based on Large-Area Layered PtSe2 FilmsNano Letters, 2018
- Electrical devices from top-down structured platinum diselenide filmsnpj 2D Materials and Applications, 2018
- High-Performance Hybrid Electronic Devices from Layered PtSe2 Films Grown at Low TemperatureACS Nano, 2016
- 2D materials and van der Waals heterostructuresScience, 2016
- Monolayer PtSe2, a New Semiconducting Transition-Metal-Dichalcogenide, Epitaxially Grown by Direct Selenization of PtNano Letters, 2015
- Spin and pseudospins in layered transition metal dichalcogenidesNature Physics, 2014
- Computational Search for Single-Layer Transition-Metal Dichalcogenide PhotocatalystsThe Journal of Physical Chemistry C, 2013
- The chemistry of two-dimensional layered transition metal dichalcogenide nanosheetsNature Chemistry, 2013
- Electronics and optoelectronics of two-dimensional transition metal dichalcogenidesNature Nanotechnology, 2012
- The electronic structures of platinum dichalcogenides: PtS2, PtSe2and PtTe2Journal of Physics C: Solid State Physics, 1986