EUV Light Centroid Control via Multi-Sensor Calibration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing EUV light generating apparatuses face challenges in accurately controlling the centroid of EUV light, leading to inefficiencies and increased debris pollution, due to individual differences in EUV light sensor sensitivity and potential pollution of sensors and optical systems.
Innovation Solution
The apparatus includes multiple EUV light sensors to measure energy from different directions, an application position adjusting unit, and a controller that calibrates the desired centroid based on measured energy and sensor data, using algorithms to adjust the laser light focus and maintain optimal EUV light emission while continuously monitoring and correcting for deviations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a single EUV light sensor is used to measure EUV light energy, then the device complexity is low, but the measurement precision deteriorates due to individual sensor sensitivity differences and potential pollution
Solution Approach 1:
The patent divides the single sensor measurement function into multiple sensors arranged in specific spatial positions. Each sensor measures EUV light from a different direction, and the controller integrates these multiple measurements to calculate the centroid with higher precision, overcoming the limitations of individual sensor sensitivity variations and pollution.
Solution Approach 2:
The controller continuously receives measurement data from multiple EUV light sensors, compares the measured centroid position with the desired centroid, and generates feedback signals to adjust the laser light application position. This closed-loop feedback system maintains measurement precision despite sensor drift or pollution over time.
2Manufacturing precision
If the laser light application position is fixed, then the device complexity is low, but the manufacturing precision deteriorates due to shooting mismatch
Solution Approach 1:
The patent transforms the fixed laser light application position into a dynamic, adjustable position. The application position adjusting unit receives control signals from the controller and continuously modifies the laser light focal point position on the target based on real-time centroid measurements, enabling precise centroid control while adapting to target variations and sensor drift.
Solution Approach 2:
The patent replaces manual or fixed mechanical positioning with an automated control system. The controller uses measurement data from EUV light sensors to calculate the desired application position and automatically adjusts the laser light focusing, substituting mechanical precision requirements with computational precision and feedback control.
3Reliability
If continuous monitoring and calibration of EUV light centroid is implemented, then the reliability improves, but the loss of time increases due to continuous calibration processes
Solution Approach 1:
The patent implements continuous monitoring and calibration during EUV light generation operations. Multiple sensors continuously measure EUV light energy, and the controller continuously updates the application position based on real-time measurements, ensuring reliable and stable EUV light emission without interruption or significant time loss.
Solution Approach 2:
The system performs preliminary calibration by establishing the relationship between sensor measurements and actual centroid positions during initial setup or periodic maintenance. This preliminary calibration data is stored and used to accelerate subsequent real-time corrections, reducing the time needed for continuous calibration while maintaining reliability.
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
This solution enables precise control of the EUV light centroid, reducing shooting mismatch and maintaining high operation rates by continuously calibrating the desired centroid, thus improving EUV light emission efficiency and reducing debris pollution.
Implementation Method 1
a plurality of EUV light sensors configured to measure energy of EUV light
Implementation Method 2
EUV light being generated by applying laser light to a target supplied to a predetermined region in a chamber
Implementation Method 3
an LPP (Laser Produced Plasma) type apparatus using plasma that is generated by applying laser light to a target
Data Source
AI summary
An EUV light generating apparatus includes: EUV light sensors configured to measure energy of EUV light from mutually different directions, the EUV light being generated by applying laser light to a target supplied to a predetermined region in a chamber; an application position adjusting unit configured to adjust an application position of the laser light to the target supplied to the predetermined region; and a controller configured to control the application position adjusting unit such that a centroid of the EUV light becomes a target desired centroid, the centroid of the EUV light being specified from measurement results of the EUV light sensors. The controller calibrates the target desired centroid based on EUV light centroids obtained from the energy of the EUV light measured by the EUV light sensors, and a parameter related to the measured energy of the EUV light corresponding to the EUV light centroids.