Rare Mononuclear Lithium–Carbene Complex for Atomic Layer Deposition of Lithium Containing Thin Films
Year: 2025
Type: article
Abstract: Lithium is the core material of modern battery technologies and fabricating the lithium‐containing materials with atomic layer deposition (ALD) confers significant benefits in control of film composition and thickness. In this work, a new mononuclear N‐heterocyclic carbene (NHC) stabilized lithium complex, [Li( tBu NHC)(hmds)], is introduced as a promising precursor for ALD of lithium‐containing thin films. Structural characterization is performed, comparing density functional theory (DFT) and single‐crystal X‐ray diffraction (SC‐XRD), confirming a rare mononuclear structure. Favorable thermal properties for ALD applications are evidenced by thermogravimetric analysis (TGA). The compound exhibits a low melting point, clean evaporation, and its volatility parameters are encouraging compared to other lithium precursors. ALD trials using [Li( tBu NHC)(hmds)] with ozone demonstrate its effectiveness in depositing LiSi x O y films. The ALD process exhibits a saturated growth per cycle (GPC) of 0.95 Å. Compositional analysis using Rutherford backscattering spectrometry/nuclear reaction analysis (RBS/NRA), X‐ray photoelectron spectrometry (XPS), and glow discharge optical emission spectrometry (GD‐OES), confirms the presence of lithium and silicon in the expected ratios. This work not only presents a new ALD precursor but also contributes to the understanding of lithium chemistry, offering insights into the intriguing coordination chemistry and thermal behavior of lithium complexes stabilized by NHC ligands.
Institutions: Ruhr University Bochum, Fraunhofer Institute for Microelectronic Circuits and Systems, University College Cork, Tyndall National Institute, Leibniz Institute for Solid State and Materials Research, Federal Institute For Materials Research and Testing, Technische Universität Ilmenau, Technische Universität Dresden
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $5,510
Awards: G2710589720, G3940635889, Neuartige Vorstufen für die räumlich getrennte Atomlagenabscheidung und Plasmaprozesse zur Herstellung von funktionellen Materialien in der fortgeschrittenen Anwendung, G5692870057, G653274269, A European Training Network for Functional Hybrid Coatings by Molecular Layer Deposition, Access to European Infrastructure for Nanoelectronics
OpenAlex ID: W4414026198