片上中红外波长调制光谱气体传感技术  

On-Chip Mid-Infrared Wavelength Modulation Spectroscopy Gas Sensing Technique

作　　者：皮明权 黄一俊 郑传涛[1,2] 赵焕 彭子航 杨悦 闵昱婷[1,2] 宋芳 王一丁 Pi Mingquan;Huang Yijun;Zheng Chuantao;Zhao Huan;Peng Zihang;Yang Yue;Min Yuting;Song Fang;Wang Yiding(State Key Laboratory of Integrated Optoelectronics,College of Electronic Science and Engineering,Jilin University,Changchun130012,Jilin,China;Jilin Provincial Engineering Research Center of Infrared Gas Sensing Technique,Changchun 130012,Jilin,China)

机构地区：[1]吉林大学电子科学与工程学院集成光电子学国家重点联合实验室,吉林长春130012 [2]吉林省红外气体传感技术工程研究中心,吉林长春130012

出　　处：《光学学报》2023年第18期171-177,共7页Acta Optica Sinica

基　　金：国家自然科学基金(62175087,62235016,61960206004,62105118);吉林省科技发展计划(20230201054GX);长春市重点研发项目(21ZGN24)。

摘　　要：制备了下包层为氟化镁、芯层为硫系玻璃的梯形光波导甲烷传感器,采用片上波长调制光谱技术,开展了气体检测实验,将仿真结果与实验结果进行了对比,证明了基于波长调制光谱的仿真模型的准确性。狭缝波导是常用的非悬浮波导气体传感器结构,优化了下包层为氟化镁、芯层为硫系玻璃的狭缝波导传感器结构,外限制因子达到了42%。根据实验测试得到的噪声幅值,理论研究了狭缝波导气体传感器和波长调制光谱技术结合的性能,分析了环境压强和工艺误差对狭缝波导气体传感器性能的影响。本工作为基于波长调制光谱的片上气体传感器的设计提供了指导。Objective On-chip gas sensor based on infrared absorption spectroscopy is useful for environmental detection because of its small size and low power consumption.Direct absorption spectroscopy is a commonly used detection technique for onchip gas sensors,but the noise of this detection method is high.The wavelength modulation spectroscopy technique can suppress noise.The combination of the wavelength modulation spectroscopy technique with the on-chip gas sensor can improve the performance of the sensor.However,the waveguide parameters including external confinement factor,loss,and length influence the second harmonic signal.A slot waveguide can increase the external confinement factor by using the mode field distributed in the slot for sensing.We provide guidance for the design of on-chip gas sensors based on wavelength modulation spectroscopy.Methods The optical field distribution results and external confinement factor are obtained by COMSOL Multiphysics with electromagnetic waves and frequency domain module.The optical parameters of the waveguide are set at the wavelength of 3291 nm.The chalcogenide rectangular waveguide is fabricated by the lift-off method.The process of the lift-off method includes spinning photoresist,lithography,development,thermal evaporation,and removal of photoresist.The noise of the waveguide sensing system is used for simulation analysis.The second harmonic signal amplitude of the on-chip gas sensor is simulated by MATLAB.The important parameters of the simulation model include gas absorption parameters at 3291 nm,waveguide parameters,and laser parameters.The simulated limit of detection is calculated based on the signal-to-noise ratio.Results and Discussions The trapezoid waveguide morphology is shown in Fig.2,and the external confinement factor of the waveguide is about 8%.The CH_(4)sensing results based on wavelength modulation spectroscopy at 3291 nm show that the response result is linear(Fig.5).The slot waveguide structure with magnesium fluoride as the lower cladding layer and c

关 键 词：光波导 波长调制光谱 片上集成 光波导传感器 气体传感器 

分 类 号：TN252[电子电信—物理电子学]