Embedded Photonic Sensor Linearization Across Temperature and Pressure
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Photonic sensors used in semiconductor processing exhibit non-linear responses due to environmental factors, leading to poor accuracy and the need for extensive lookup databases, which are computationally expensive and unsuitable for real-time control in high-precision environments.
Innovation Solution
A parameter optimization approach is applied to generate calibration constants for a modified Beer-Lambert formula, allowing for a one-to-one relationship between photonic sensor signals and species concentration, increasing the operational temperature and pressure range, and reducing computational requirements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a photonic sensor is calibrated for a specific temperature and pressure range, then measurement precision is improved within that narrow range, but adaptability deteriorates when operational conditions go outside the calibration range
Solution Approach 1:
The patent applies parameter changes by modifying the Beer-Lambert law to include temperature and pressure as variables. The modified formula C = (1/αL) × ln(I₀/I) × f(T, P) allows the concentration calculation to adapt to different temperature and pressure conditions through the function f(T, P), which compensates for environmental variations and extends the sensor's operational range while maintaining accuracy
2Measurement precision
If an extensive lookup database is used to correct sensor responses, then measurement precision is improved, but device complexity and computational requirements increase
Solution Approach 1:
The patent replaces the mechanical/computational lookup database system with a mathematical model-based system. Instead of storing extensive calibration data in lookup tables and performing complex interpolations, the modified Beer-Lambert law provides a direct analytical solution that calculates concentration using a simple formula with temperature and pressure compensation, significantly reducing computational complexity while maintaining precision
3Measurement precision
If a lookup database approach is used for sensor calibration, then measurement precision is improved, but productivity deteriorates due to computational expense in real-time control
Solution Approach 1:
The patent substitutes the computationally intensive lookup database approach with an analytical mathematical model. The modified Beer-Lambert law enables real-time concentration calculations using simple arithmetic operations (multiplication, division, natural logarithm) combined with temperature and pressure compensation functions, eliminating the need for extensive database queries and complex interpolations, thus achieving both high precision and fast real-time processing suitable for semiconductor manufacturing control
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 modified concentration formula improves accuracy to up to 0.05% deviation, enabling real-time or near-real-time measurements and reducing computational complexity, suitable for semiconductor processing.
Implementation Method 1
converting the intensity signals into species concentrations through the use of a modified Beer-Lambert law
Data Source
AI summary
In embodiments disclosed herein, a method for calibrating a photonic sensor includes collecting a plurality of concentration measurements with a photonic sensor with a plurality of different reference gas mixtures under various temperature and pressure environments, where each reference gas mixture includes a known species concentration, and implementing a parameter optimization routine to minimize deviations between the known species concentrations and the plurality of concentration measurements obtained by the photonic sensor, where the optimization routine generates one or more calibration constants. In an embodiment, the method may further include integrating the one or more calibration constants into a modified concentration formula, and storing the modified concentration formula in a controller used to operate the photonic sensor.