In Situ Assembling of Glass Microspheres and Bonding Force Analysis by the Ultraviolet–Near-Infrared Dual-Beam Optical Tweezer System

[Image: see text] Microresonators show great potential as interlayer routing solutions for multilayered three-dimensional (3D) photonic communication networks. New techniques are needed for the convenient and in situ manipulation and immobilization of glass microspheres into functional structures. Herein, near-infrared (NIR) and ultraviolet (UV) lasers were used as optical tweezers to precisely arrange silica microspheres and UV-initiated immobilization in a 3D space. The NIR laser was used to trap targeted microspheres, and the UV laser was focused to immobilize the trapped microspheres in 3-methacryloxypropyltrimethoxysilane (MOPS) in ∼6 s. Optical force spectroscopy was performed using the optical tweezers to measure individual bond strength. Next, functional triangular pedestals were designed to flexibly control the gap space for vertical router applications in 3D photonic networks. Thus, the designed UV–NIR dual-beam optical tweezer system can be used to assemble arbitrary functional 3D structures, making it a valuable tool for microfabrication, photonics, and optical communication applications.