Micromachined Integrated Optics for Free-Space Interconnections

A novel surface micro-machined micro-optical bench (MOB) has been demonstrated. Free-space micro-optics such as micro-Fresnel lenses, rotatable mirrors, beam-splitters and gratings are implemented on a single Si chip using IC-like microfabrication processes. Self-aligned hybrid integration with semiconductor lasers are also demonstrated for the first time. The MOB technology realizes a microoptical system on a single Si chip and has significant impact on free-space integrated optics, optical switching, optical data storage, and optoelectronic packaging. free-space. Using this new technique, threedimensional micro-optical components can be fabricated integrally on a single Si chip. The Si substrate serves as a “micro-optical bench (MOB)” on which micro-lenses, mirrors, gratings and other optical components are pre-aligned in the mask layout stage using computer-aided design and then constructed by microfabrication. Additional fine adjustment can be achieved by the on-chip micro-actuators and micropositioners such as rotational and translational stages. With hybrid integration of active optical devices, a complete optical system can be constructed on the MOB, as illustrated in Fig. 1.