The role of silicon micromachining in optical fiber sensing technologies

Silicon micromachining has the advantage of small scale and easy integration with electronic circuits and sensors, resulting in the production of miniaturized and smart microsystems with moving parts. The size of the microelectromechanical systems/microoptoelectromechanical systems devices is immediately compatible with the size of integrated optics (IOs), and is appropriate to control or manipulate optical radiations. This technology is, therefore, suitable to fabricate precision-defined optical components and offers relatively easy alignment procedures of optical parts. This paper examines the contribution of micromachined structures in the specific context of optical fiber sensing technology. A number of demonstrator sensors will be discussed, with special emphasis on sensors with micromachined IO structures, nanoscale scanning optical microscope sensors, and fiber IO circuits coupling systems.