集成光杨氏干涉计生化传感器的设计和制备

Design and fabrication of a biochemical sensor based on an integrated optical Young interferometer

报道一种结构新颖的集成光杨氏干涉计生化传感器。利用微光机电系统(MOEMS)加工工艺结合离子交换技术在玻璃基底上制作出成对的平行单模光波导阵列,并在每对波导中一条的中间区段淀积一层具有梯度末端的TiO2薄膜,覆膜波导用作传感,裸露波导作为参比,从而构成集成光杨氏干涉计芯片。研制结果表明,这种传感器与传统的集成光杨氏干涉计相比,不仅省去了Y型功率分配器和低折射率介质保护层,而且利用简单的狭缝探测器取代了昂贵的电荷耦合器(CCD)探测器,具有结构简单、制作容易和使用方便等优点。

This paper reports an integrated optical Young interferometer with a novel structure for biochemical sensing application.Pairs of parallel straight single-mode glass channel waveguides are prepared on a glass substrate by using the micro-optoelectromechanical system（MOEMS） technique and the ion-exchange method.With a sputtering mask a tapered layer of TiO2 is deposited on the middle region of one of each channel pair,leading to a great enhancement of the evanescent field in the covered region based on the tapered velocity coupling theory.Using the TiO2-coated channel as the sensing arm and the uncovered one as the reference arm,each pair of channel waveguides can be used as an IO Young interferometer sensor.The results show that compared with the conventional IO Young interferometer sensors,our sensor not only eliminates both the Y-branch power splitter and the low-index protection coating but also uses a simple slit photodetector to replace the expensive CCD detector.These advantages make our sensor easy to fabricate and convenient to use.