Multimode Waveguide Metrology for Compact Multi-Wavelength Measurement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current metrology systems for lithographic processes are large and occupy significant space, limiting high-volume manufacturing output due to their inability to measure multiple wavelengths simultaneously with a compact footprint.
Innovation Solution
A compact metrology system utilizing a radiation source, optical elements, multimode waveguides, and processors to generate and analyze scattered radiation, enabling simultaneous measurement of multiple wavelengths and determining target properties with high accuracy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If existing metrology systems measure multiple wavelengths simultaneously, then measurement accuracy and throughput are improved, but device size and footprint increase significantly
Solution Approach 1:
The patent implements nested optical paths where multiple wavelength measurements are performed through hierarchical nesting of optical components. The system nests multiple measurement functions within a single integrated optical path, allowing simultaneous multi-wavelength measurement while maintaining a compact footprint by placing measurement components within each other's spatial envelopes.
Solution Approach 2:
The patent transitions from sequential spatial measurement to simultaneous spectral measurement by adding the wavelength dimension to the measurement process. Instead of measuring different wavelengths at different times or locations, the system measures all wavelengths simultaneously through spectral analysis, effectively using the wavelength dimension to multiply measurement capacity without increasing physical footprint.
2Measurement precision
If metrology systems occupy large space, then measurement capabilities are enhanced, but manufacturing throughput decreases
Solution Approach 1:
The patent enables continuous multi-wavelength measurement by eliminating sequential measurement steps. The optical system continuously captures and analyzes multiple wavelengths simultaneously, removing idle time between measurements and maintaining continuous useful action throughout the measurement process, thereby increasing manufacturing throughput without sacrificing measurement capability.
Solution Approach 2:
The system performs preliminary spectral analysis by capturing the complete spectrum in a single measurement event. By preliminarily analyzing all wavelength components simultaneously rather than sequentially, the system eliminates subsequent measurement steps and enables immediate processing decisions, thereby accelerating manufacturing throughput.
3Device complexity
If multiple wavelengths are measured sequentially, then device complexity is reduced, but measurement time increases
Solution Approach 1:
The patent changes the measurement parameter from temporal sequencing to spectral simultaneity. Instead of varying the measurement time parameter to measure different wavelengths sequentially, the system changes to measuring all wavelengths at the same time by utilizing spectral dispersion and simultaneous detection, thereby reducing measurement time without significantly increasing device complexity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The system achieves high-throughput, accurate measurements of target properties across multiple wavelengths in a reduced footprint, enhancing manufacturing efficiency and precision.
Implementation Method 1
an integrated optical device comprising a multimode waveguide configured to interfere a second portion of the scattered radiation using modes of the multimode waveguide
Data Source
AI summary
A metrology system comprises a radiation source, an optical element, first and second detectors, an integrated optical device comprising a multimode waveguide, and a processor. The radiation source generates radiation. The optical element directs radiation toward a target to generate scattered radiation from the target. The first detector receives a first portion of the scattered radiation and generates a first detection signal based on the received first portion. The multimode waveguide interferes a second portion of the scattered radiation using modes of the multimode waveguide. The second detector receives the interfered second portion and generates a second detection signal based on the received interfered second portion. The processor receives the first and second detection signals. The processor analyzes the received first portion, the received interfered second portion, and a propagation property of the multimode waveguide. The processor determines the property of the target based on the analysis.