Atomic layer deposition of tin oxide using tetraethyltin to produce high-capacity Li-ion batteries

Abstract

The authors deposited thin films of tin oxide on substrates of silicon and stainless steel by using atomic layer deposition (ALD) with tetraethyltin precursors. In this process, the authors used various coreactants such as water, oxygen, remote oxygen plasma, hydrogen peroxide, and ozone. The growth rates of films were studied as functions of the deposition temperature, the pulse times of the precursor and coreactant, and the number of ALD cycles, and the optimal growth conditions were determined. The film growth rates were found to be 0.025, 0.045, and 0.07 nm per cycle within the optimal growth conditions and ALD temperature windows for H2O2, O3, and O2 plasma, respectively. Using H2O or O2 did not prompt film growth. The films deposited using O3 and H2O2 had good continuity and low roughness, while the morphology of a coating prepared using oxygen plasma depended greatly on the deposition temperature. The films produced at temperatures below 300 °C were amorphous, irrespective of the coreactant used. X-ray photoelectron spectroscopy revealed that the samples mainly contained tin in the +4 oxidation state. The films deposited on stainless steel had high reversible capacity above 900 mA h g−1, exceptional cycleability, and good electrochemical performance as anodes for lithium-ion batteries.

Atomic Layer Deposition of Li–Me–O Thin Films as Electrode Materials for Nanodevices Power Sources

“…For the films Li-O deposited with the use of oxygen plasma, the growth rate diminishes with the increase in temperature. The same influence of temperature was observed earlier in SnO2 films [8]. The growth rates of H2O(500)+Al(100) and Po2(400)+Al(50) films are similar.…”

“…For both samples, the maximum growth rate was observed at 250 °C and may have been caused by secondary processes [9,10] that lead to nanocrystal formation and/or formation lithium aluminate. The minimal values of growth rates (0.16-0.22 nm per cycle) were observed for the synthesis at 300 °C and are consistent with growth rates observed in the ALD process [4,5,8]. The growth rates for films of different compositions deposited at 250 °C are presented in Figure 2.…”

Atomic Layer Deposition of NiO to Produce Active Material for Thin-Film Lithium-Ion Batteries

“…Then, the substrates were cleaned using Piranha etch (70% H 2 SO 4 and 30% H 2 O 2 ) for 20 min to remove organic residues and generate hydroxyl surface species. Finally, the samples were rinsed in double deionized water and dried in inert gas atmosphere [55].…”

In-system photoelectron spectroscopy study of tin oxide layers produced from tetrakis(dimethylamino)tin by plasma enhanced atomic layer deposition

“…Since perovskite and silicon heterojunction solar cells both feature layers, which are susceptible to degradation at elevated temperatures, it is mandatory for the solar cell applications to deposit SnO2 below 200°C 14 . Due to the high reactivity of the oxygen plasma 15 , plasma enhanced atomic layer deposition (PEALD) with an appropriate precursor can allow these low deposition temperatures. Usage of a highly reactive plasma might damage the functional layers underneath, as was shown for PEALD of MoOx in silicon heterojunction cells.…”