Scanner Stability Module Thread for Lithography Alignment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current lithographic systems require multiple scanner stability module threads to manage different alignment strategies, leading to increased complexity and reduced availability, as a single thread cannot effectively control scanners with varying alignment strategies for production wafers.
Innovation Solution
Implementing a single scanner stability module thread per scanner by gathering measure-side grid information using monitor wafers with a fixed alignment strategy, allowing the module to calculate and compensate for wafer shape distortions and overlay errors across different alignment strategies used for customer products.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If multiple scanner stability module threads are implemented to manage different alignment strategies, then the system can handle various customer products with different alignment requirements, but the device complexity increases and availability decreases
Solution Approach 1:
The patent implements a universal scanner stability module thread that can handle multiple alignment strategies through a selection mechanism. Instead of creating separate threads for each alignment strategy, the system uses a single multi-functional thread that selects the appropriate alignment strategy based on the customer product requirements, thereby reducing device complexity while maintaining adaptability
Solution Approach 2:
The system dynamically selects which alignment strategy to apply based on the specific customer product being processed. The scanner stability module thread adapts its behavior in real-time by choosing from multiple alignment strategies (such as wafer-level, die-level, or feature-level alignment) depending on the requirements of the current production task, eliminating the need for multiple static threads
2Adaptability or versatility
If multiple scanner stability module threads are implemented to manage different alignment strategies, then various alignment strategies can be controlled, but the system availability reduces
Solution Approach 1:
The patent merges multiple scanner stability module threads into a single unified thread that handles all alignment strategies. By combining the functionality of multiple threads into one, the system eliminates the overhead and potential conflicts associated with running multiple concurrent threads, thereby improving scanner availability while still supporting multiple alignment strategies through intelligent selection and switching mechanisms
3Device complexity
If a single scanner stability module thread is used, then device complexity and availability are improved, but the ability to effectively control scanners with varying alignment strategies deteriorates
Solution Approach 1:
The single scanner stability module thread incorporates self-service capabilities by automatically selecting the appropriate alignment strategy based on the customer product requirements. The system monitors the alignment strategy needs and autonomously switches between different alignment approaches (wafer-level, die-level, feature-level) without requiring external intervention, thereby maintaining full control capability while keeping the system simple
Solution Approach 2:
The single thread implements dynamic adaptability by continuously adjusting which alignment strategy it applies based on real-time product requirements. The system can switch between multiple alignment strategies dynamically during operation, allowing a single thread to effectively control scanners for various customer products with different alignment needs
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
Enables the operation of a single scanner stability module thread per scanner, simplifying control and improving availability by accurately accounting for alignment-related effects, regardless of the number of alignment strategies employed, thus enhancing fabrication automation and reducing the need for multiple threads.
Implementation Method 1
A fast and non-invasive form of specialized inspection tool is a scatterometer in which a beam of radiation is directed onto a target on the surface of the substrate and properties of the scattered or reflected beam are measured
Implementation Method 2
Spectroscopic scatterometers direct a broadband radiation beam onto the substrate and measure the spectrum (intensity as a function of wavelength) of the radiation scattered into a particular narrow angular range
Implementation Method 3
Angularly-resolved scatterometers use a monochromatic radiation beam and measure the intensity of the scattered radiation as a function of angle
Data Source
Figure 1~2
Figure 3~4
Figure 5
AI summary
A method controls a scanning function of a lithographic apparatus. A first alignment strategy is used. A monitor wafer is exposed to determine baseline control parameters pertaining to the scanning function. The baseline control parameters are periodically retrieved from the monitor wafer. Parameter drift is determined from the baseline control parameters. Corrective action is taken based on the determination. A production wafer is exposed using a second alignment strategy, different to the first alignment strategy. The corrective action is modified so as to be substantially closer to the correction that would have been made had the second alignment strategy been used in exposing the monitor wafer.