Scatterometry is a well-established,fast and precise optical metrology method used for the characterization of sub-lambda periodic features.The Fourier scatterometry method,by analyzing the Fourier plane,makes it poss...Scatterometry is a well-established,fast and precise optical metrology method used for the characterization of sub-lambda periodic features.The Fourier scatterometry method,by analyzing the Fourier plane,makes it possible to collect the angle-resolved diffraction spectrum without any mechanical scanning.To improve the depth sensitivity of this method,we combine it with white light interferometry.We show the exemplary application of the method on a silicon line grating.To characterize the sub-lambda features of the grating structures,we apply a model-based reconstruction approach by comparing simulated and measured spectra.All simulations are based on the rigorous coupled-wave analysis method.展开更多
Optical fiber sensor networks(OFSNs)provide powerful tools for large-scale buildings or long-distance sensing,and they can realize distributed or quasi-distributed measurement of temperature,strain,and other physical ...Optical fiber sensor networks(OFSNs)provide powerful tools for large-scale buildings or long-distance sensing,and they can realize distributed or quasi-distributed measurement of temperature,strain,and other physical quantities.This article provides some optical fiber sensor network technologies based on the white light interference technology.We discuss the key issues in the fiber white light interference network,including the topology structure of white light interferometric fiber sensor network,the node connection components,and evaluation of the maximum number of sensors in the network.A final comment about further development prospects of fiber sensor network is presented.展开更多
基金We are thankful for the technical support given by Thomas Schoder.This work was supported by the German DFG-funded priority program(SPP1327)on‘Optically generated sub-100 nm structures for technical and bio-medical applications’within the subproject‘Development of a functional sub-100 nm 3D two-photon polymerization technique and optical characterization methods’and the DFG project‘Inverse-source and inverse-diffraction problems in photonics(OS111/32-1).’。
文摘Scatterometry is a well-established,fast and precise optical metrology method used for the characterization of sub-lambda periodic features.The Fourier scatterometry method,by analyzing the Fourier plane,makes it possible to collect the angle-resolved diffraction spectrum without any mechanical scanning.To improve the depth sensitivity of this method,we combine it with white light interferometry.We show the exemplary application of the method on a silicon line grating.To characterize the sub-lambda features of the grating structures,we apply a model-based reconstruction approach by comparing simulated and measured spectra.All simulations are based on the rigorous coupled-wave analysis method.
文摘Optical fiber sensor networks(OFSNs)provide powerful tools for large-scale buildings or long-distance sensing,and they can realize distributed or quasi-distributed measurement of temperature,strain,and other physical quantities.This article provides some optical fiber sensor network technologies based on the white light interference technology.We discuss the key issues in the fiber white light interference network,including the topology structure of white light interferometric fiber sensor network,the node connection components,and evaluation of the maximum number of sensors in the network.A final comment about further development prospects of fiber sensor network is presented.