Features of the synthesis of lithium-based ternary oxide nanofilms by atomic layer deposition with LHMDS for thin-film LIBs

Abstract

The present study is devoted to the development of perspective cathode (LiNiO2) and anode (lithiated SnO2) of solid-state lithium-ion batteries with the use of atomic layer deposition. The program of synthesis included a different number (ratio, 1/1–1/3) of lithium and metal oxide (Ni, Sn) deposition cycles in one supercycle. Lithium hexamethyldisilazide (LiHMDS), bis(cyclopentadienyl)nickel (II) (NiCp2) and tetraethyl tin (TET) were used as metal-containing reagents while oxygen remote plasma was used as a counter reagent. The deposition was conducted at 300 °C on the silicon surface and stainless-steel substrates. The obtained films were annealed at 400–700 °C for 10 min. Spectral ellipsometry, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray reflectometry (XRR), X-ray diffraction (XRD) were used to characterize samples. The presence of silicon and nitrogen atoms was found in films which were not observed during deposition of lithium oxide and nickel oxide structures at the same synthesis conditions. The electrochemical behavior of synthesized Li-Ni-O and Li-Sn-O electrodes were studied.