Transition-Metal Nitride Halide Dielectrics for Transition-Metal Dichalcogenide Transistors

Abstract

Using first-principles calculations, we investigate six transition-metal nitride halides (TMNHs): HfNBr, HfNCl, TiNBr, TiNCl, ZrNBr, and ZrNCl as potential van der Waals (vdW) dielectrics for transition metal dichalcogenide (TMD) channel transistors. We calculate the exfoliation energies and bulk phonon energies and find that the six TMNHs are exfoliable and thermodynamically stable. We calculate both the optical and static dielectric constants in the in-plane and out-of-plane directions for both monolayer and bulk TMNHs. In monolayers, the out-of-plane static dielectric constant ranges from 5.04 (ZrNCl) to 6.03 (ZrNBr) whereas in-plane dielectric constants range from 13.18 (HfNBr) to 74.52 (TiNCl). We show that the bandgap of TMNHs ranges from 1.53 eV (TiNBr) to 3.36 eV (HfNCl) whereas the affinity ranges from 4.01 eV (HfNBr) to 5.60 eV (TiNCl). Finally, we estimate the dielectric leakage current density of transistors with six TMNH monolayer dielectrics with five monolayer channel TMDs (MoS2, MoSe2, MoTe2, WS2, and WSe2). For p-MOS TMD channel transistors, 19 out of 30 combinations have a smaller leakage current compared to monolayer hexagonal boron nitride (hBN), a well-known vdW dielectric. The smallest monolayer leakage current of 2.14*10-9 A/cm2 is predicted for a p-MOS WS2 transistor with HfNCl as a gate dielectric. HfNBr, HfNCl, ZrNBr, and ZrNCl are also predicted to yield small leakage currents in certain p-MOS TMD transistors.

arXiv comment13 pages, 5 figures, 1 table

References in corpus (11)

• Two-dimensional materials from high-throughput computational exfoliation of experimentally known compounds
• The Computational 2D Materials Database: High-Throughput Modeling and Discovery of Atomically Thin Crystals
• Van der Waals bonding in layered compounds from advanced first-principles calculations
• On the suitability of hBN as an insulator for 2D material-based ultrascaled CMOS devices
• Topology-Scaling Identification of Layered Solids and Stable Exfoliated 2D Materials
• High-Performance Flexible Nanoscale Field-Effect Transistors Based on Transition Metal Dichalcogenides
• First-principles study of two-dimensional van der Waals heterojunctions
• Dielectric Screening by 2D Substrates
• Spin and Charge Fluctuations in the $\alpha$-structure Layered Nitride Superconductors
• New polymorphic phase and rich phase diagram in the PdSe2-xTex system
• Low-Temperature 2D/2D Ohmic Contacts in WSe${}_2$ Field-Effect Transistors as a Platform for the 2D Metal-Insulator Transition

Cited by in corpus (3)

• High-throughput screening of 2D materials identifies p-type monolayer WS${}_2$ as potential ultra-high mobility semiconductor
• Lanthanum Oxyhalide Monolayers: An Exceptional Dielectric Companion to Two-Dimensional Semiconductors
• Ab initio property characterisation of thousands of previously unknown 2D materials