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An ultra violet (UV)-cured glassy material with less than 30 wt% organic residues was fabricated by the fast sol-gel method. The material presents high thermal stability, good optical quality and high adhesive strength. It is suitable for optical bonding and for manufacture of optical elements and micro-structured optical devices. Either soft-lithography or photo-lithography may be used for manufacture of the devices with either, thermal-curing (few hours) or UV-curing (few seconds). In this work we present the technology to fabricate optical elements at scales spanning the sub-micron to centimeter range. This technology enables mass-production of optical elements at low cost.

We investigate here the properties of fast sol-gel for optical bonding. The precursors of the fast sol-gel material are organically modified alkoxides generating a transparent hybrid (organic-inorganic) substance with silica glass-like properties whose index of refraction can be modified by the addition of various metal-oxides. The fast sol-gel method consists of rapid fabrication of a viscous resin and its subsequent dilution for long shelf life use. This material, when used as an adhesive offers the option of either a thermal or UV curing procedure. We demonstrate a bonding strength of ∼ 10 MPa when a 15 µm layer is applied between two glass elements. The bonding remained stable after an extensive −40°C – 120°C temperature cycling with minimal residual solvent evaporation at 150°C. The fast sol-gel material was tested for optical bonding between silica bulks, between silica bulk and silicon wafers and as an adhesive in silica fibre couplers.