Fabrication of a true-3D inorganic ceramic with resolution down to nanoscale using sol-gel resist precursor is demonstrated. The method has an unrestricted free-form capability, control of the ﬁll-factor, and high fabrication throughput. A systematic study of the proposed approach based on ultrafast laser 3D lithography of organic-inorganic hybrid sol-gel resin followed by a heat treatment enabled the formation of inorganic amorphous and crystalline composites guided by the composition of the initial resin.
The achieved resolution of 100 nm was obtained for 3D patterns of complex free-form architectures. Fabrication throughput of50×103voxels/s is achieved; voxel – a single volume element was recorded by a single pulse exposure. After a subsequent thermal treatment, the ceramic phase was formed depending on the temperature and duration of the heat treatment as validated by Raman micro-spectroscopy. The X-ray diffraction (XRD) revealed a gradual emergence of the crystalline phases at higher temperatures with a signature of cristobalite SiO2, a high-temperature polymorph. Also, the tetragonal ZrO2phase known for its high fracture strength was observed.
This 3D nano-sintering technique is scalable from nano- to millimeter dimensions and opens a conceptually novel route for optical 3D nano-printing of various crystalline inorganic materials deﬁned by an initial composition for diverse applications for microdevices in harsh physical and chemical environments and high temperatures.
We show that a popular hybrid organic-inorganic sol-gel resist SZ2080 can be converted into a material with entirely different properties obtained via polymer-to-ceramic transition guided by high-temperature sintering and oxidation. The silica and zirconia precursors present in the resist in the∼20% mass of inorganic component will lead to the emergence of silica and zirconia crystalline phases in the ﬁnal sintered ceramic material. Importantly, a proportional downscaling of the 3D polymerized object takes place with the signiﬁcant volume change of 40-50% dependent on annealing protocol without distortion of the proportions of the initial 3D design. The temperature-guided resizing and the composition change can be potentially tailored to form 3Dfree-form patterns of complexity which are not amenable by other micro-/nano-fabrication methods.
Read more: 3D Printing Glass-Ceramics at the Nanoscale
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