Ultrafast laser 3D nanolithography of organic–inorganic hybrid waveguide devices

On-chip micro- and nano-photonic structures are pivotal in modern industry, primarily due to their compact size, low transmission losses, and ease of integration. However, the three-dimensional (3D) bottom-up fabrication of on-chip functional structures, especially those made from inorganic materials rather than organic polymers, remains a challenge. Building inorganic devices with designed functional nanostructures on chips is critical for advancing microsystem applications. In this work, we propose a strategy for 3D nanolithography of on-chip waveguides using hybrid organic–inorganic materials through ultrafast laser-induced multiphoton absorption. The acrylate-functionalized precursors are locally cross-linked via nonlinear effects without the need for polymer additives. This process enables the direct integration of 3D photonic waveguides, resonators, and gratings onto chips, which exhibit strong stability due to densely packed silicon–oxygen molecular networks. This approach offers a promising solution for creating tailored inorganic micro- and nano-structures on chips, facilitating the development of advanced integrated functional devices.