Influence of Deposition Conditions and Thermal Treatments on Morphological and Chemical Characteristics of Li6.75La3Zr1.75Ta0.25O12 Thin Films Deposited by Nanosecond PLD

Abstract

The production of thin films has been extensively studied due to their unique properties that make them highly useful in a wide range of scientific and technological applications. Obtaining thin films with well-defined stoichiometry and crystallinity is a challenging task, especially when dealing with materials of complex stoichiometry. Among diverse methodologies for the manufacture of thin films, pulsed laser deposition (PLD) stands out as a versatile technique for producing crystalline films with complex chemical compositions. In this study, nanosecond PLD was employed to manufacture thin films of Ta-doped Li7La3Zr2O12 (LLZTO), a garnet-like oxide that has been proposed as solid electrolyte for Li-ion solid state batteries. Two distinct deposition atmospheres were investigated: vacuum conditions at 10−3 Pa and an oxygen-enriched environment with 10 Pa of O2 gas buffer. To mitigate lithium losses during deposition, a minor addition of lithium oxide was incorporated into the target. The effects of deposition atmosphere and the impact of post-deposition annealing on the structural, compositional, and morphological properties of LLZTO thin films were analysed through a multi-technique approach. The results suggest deposition under oxygen pressure led to the growth of compact, crystalline films characterized by homogenous elemental distribution across the surface and throughout the film’s depth. These films closely resemble the composition of the target LLZTO material, offering valuable insights for the fabrication of high-quality complex oxide thin films.

Thin-film microbattery fabrication by PLD: a comprehensive mini-review

“…In both of them, Ta-doped LLZO target material was enriched in Li content to balance the inevitable Li loss during deposition. Curcio et al (2023) deposited 2D films at different deposition pressure and post deposition heat treatment. Crystalline LLZTO film was deposited at 10 Pa of O 2 at RT (Figure 3), while post deposition treatment caused Li-poor phase formation (Curcio et al, 2023).…”

“…Curcio et al (2023) deposited 2D films at different deposition pressure and post deposition heat treatment. Crystalline LLZTO film was deposited at 10 Pa of O 2 at RT (Figure 3), while post deposition treatment caused Li-poor phase formation (Curcio et al, 2023). While Morozov et al (2022) studied the correlation among deposition conditions and the microstructure at the interface between LCO and Ta-doped LLZO deposited via PLD.…”