2D Indium Phosphorus Sulfide (In2P3S9): An Emerging van der Waals High‐k Dielectrics. Issue 5 (25th November 2021)

• Record Type: Journal Article
• Authors: Zhu, Cheng‐Yi; Qin, Jing‐Kai; Huang, Pei‐Yu; Sun, Hai‐Lin; Sun, Nie‐Feng; Shi, Yan‐Lei; Zhen, Liang; Xu, Cheng‐Yan
• Is Part Of: Small. Volume 18:Issue 5(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-11-25
• Subjects: 2D materials -- field‐effect transistors -- high‐k dielectrics -- van der Waals materials; Nanotechnology -- Periodicals; Nanoparticles -- Periodicals; Microtechnology -- Periodicals; 620.5
• DOI: 10.1002/smll.202104401
• Languages: English
• ISSNs: 1613-6810

Abstract

Abstract: 2D van der Waals (vdW) semiconductors hold great potentials for more‐than‐Moore field‐effect transistors (FETs), and the efficient utilization of their theoretical performance requires compatible high‐ k dielectrics to guarantee the high gate coupling efficiency. The deposition of traditional high‐ k dielectric oxide films on 2D materials usually generates interface concerns, thereby causing the carrier scattering and degeneration of device performance. Here, utilizing a space‐confined epitaxy growth approach, the authors successfully obtained air‐stable ultrathin indium phosphorus sulfide (In2 P3 S9 ) nanosheets, the thickness of which can be scaled down to monolayer limit (≈ 0.69 nm) due to its layered structure. 2D In2 P3 S9 exhibits excellent insulating properties, with a high dielectric constant (≈ 24) and large breakdown voltage (≈ 8.1 MV cm −1 ) at room temperature. Serving as gate insulator, ultrathin In2 P3 S9 nanosheet can be integrated into MoS2 FETs with high‐quality dielectric/semiconductor interface, thus providing a competitive electrical performance of device with subthreshold swings (SS) down to 88 mV dec −1 and a high ON/OFF ratio of 10 5 . This study proves an important strategy to prepare 2D vdW high‐ k dielectrics, and greatly facilitates the ongoing research of 2D materials for functional electronics. Abstract : Ultrathin indium phosphorus sulfide (In2 P3 S9 ) nanosheets are obtained utilizing a space‐confined epitaxy growth approach, which exhibits a high dielectric constant (≈24) and large breakdown voltage (≈8.1 MV cm −1 ) at room temperature. The excellent insulating properties make it suitable for integration into 2D field‐effect transistors as dielectric layer, which can provide an efficient modulation for the carrier density in a semiconducting channel.