UV Control System Diffusive Surface for Lithography Dose Precision
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional systems for collecting fluorescent radiation in deep ultraviolet (DUV) dose control systems of lithographic apparatuses are not effective or well-controlled, leading to inefficiencies in DUV radiation measurement and calibration.
Innovation Solution
An ultraviolet radiation control system comprising a housing with a conversion crystal that converts UV radiation to fluorescent radiation, and a plurality of photodetectors to detect the intensity of the scattered fluorescent radiation, with at least one diffusive surface on or in the conversion crystal to increase the intensity of the scattered radiation, enhancing collection efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional collection methods for fluorescent radiation are used, then the system structure remains simple, but the collection efficiency and measurement precision are insufficient
Solution Approach 1:
The patent introduces a diffusive surface as an intermediary element between the conversion crystal and photodetectors. This diffusive surface scatters the fluorescent radiation, increasing the probability of photon detection by redirecting light paths toward the photodetector surfaces, thereby improving measurement precision without requiring complex optical systems
Solution Approach 2:
The patent modifies the physical parameters of the conversion crystal by incorporating diffusive surfaces with specific optical properties. By changing the surface characteristics (diffusivity, reflectivity) and geometric parameters (surface area, positioning), the system achieves enhanced fluorescent light collection efficiency while maintaining structural simplicity
2Measurement precision
If the intensity of fluorescent radiation is increased, then the measurement precision improves, but the manufacturing cost increases
Solution Approach 1:
The patent achieves increased signal intensity by modifying parameters of existing components rather than introducing new expensive technologies. The diffusive surface parameters (material composition, surface roughness, geometric configuration) are optimized to maximize light scattering efficiency, thereby enhancing the fluorescent signal detected by photodetectors without proportionally increasing manufacturing costs
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 provides a more robust and reproducible method for collecting fluorescent light, ensuring precise control of DUV radiation and reducing manufacturing costs by increasing the intensity of the signal detected by photodetectors.
Implementation Method 1
a conversion crystal, disposed on or in the housing, configured to convert an ultraviolet radiation to a fluorescent radiation
Implementation Method 2
at least one diffusive surface, disposed on or in the conversion crystal, configured to increase the intensity of the scattered portion of the fluorescent radiation
Implementation Method 3
a plurality of photodetectors configured to detect an intensity of a scattered portion of the fluorescent radiation
Data Source
AI summary
The present disclosure provides an ultraviolet radiation control system and a related method for control an ultraviolet radiation in a lithographic apparatus. The ultraviolet radiation control system comprises a housing; a conversion crystal (540), disposed on or in the housing, configured to convert an ultraviolet radiation to a fluorescent radiation; a plurality of photodetectors (550) configured to detect an intensity of a scattered portion of the fluorescent radiation; and at least one diffusive surface (545), disposed on or in the conversion crystal, configured to increase the intensity of the scattered portion of the fluorescent radiation.