Room-temperature deposition of large-area dielectric thin films via vacuum ultraviolet (VUV) photo-processes synthesis

The fabrication of oxide thin films typically requires high temperatures exceeding 900 °C and thermal equilibrium conditions, which pose significant challenges for thermal budget management. To address these limitations, this study demonstrates that a 172 nm vacuum ultraviolet (VUV) microplasma flat lamp can enable the room-temperature synthesis of SiO₂ using tetraethoxysilane (TEOS) as a precursor. The high-energy VUV photons facilitate a direct liquid-to-solid photochemical transformation, eliminating the need for elevated temperatures. Building on this success, the roomtemperature synthesis of Al₂O₃ thin films was also investigated. The feasibility of VUV-assisted Al₂O₃ thin layer deposition was confirmed by its characterization and further development of the photo-processes will be discussed in detail.