Lithography Cluster Controller for Overlay Precision
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In lithography processes, achieving precise overlay alignment across multiple substrates within a lot is challenging due to varying properties among processing units and substrates, leading to suboptimal superposition precision.
Innovation Solution
A cluster-type lithography apparatus with a controller that determines the appropriate processing unit for each substrate based on specific information, allowing parallel processing with recipe information corresponding to the lot, ensuring precise pattern formation across multiple substrates.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If substrates are processed by arbitrary processing units among multiple processing units, then productivity is improved through parallel processing, but overlay precision deteriorates due to varying properties among processing units and substrates
Solution Approach 1:
The patent applies local quality by assigning specific processing units to specific substrates based on their individual properties. The determination unit identifies matching pairs where the processing unit's characteristics (such as stage position, illumination system properties, or lens characteristics) are optimized for each substrate's specific requirements (such as pattern density, feature size, or material properties). This ensures that each substrate receives processing from the most suitable processing unit, maintaining high overlay precision while utilizing multiple processing units in parallel for improved productivity.
2Speed
If multiple processing units are used in parallel, then processing speed is improved, but consistency of pattern formation deteriorates due to property variations among processing units
Solution Approach 1:
The patent implements parameter changes by dynamically adjusting processing parameters based on the matched processing unit and substrate combination. The determination unit selects processing units whose operational parameters (such as exposure energy, focus position, scan speed, or illumination wavelength) are optimized for each substrate's specific characteristics. This allows each processing unit to operate at its optimal parameter set, ensuring consistent pattern formation quality across all substrates processed in parallel while maintaining high processing speed.
Data Source
AI summary
A lithography apparatus has a plurality of processing units configured to respectively perform patternings on a plurality of substrates that belong to a lot, and a controller configured to perform, based on specific information that specifies one of the plurality of substrates, determination of one of the plurality of processing units that processes the one of the plurality of substrates, and control the plurality of processing units such that the patternings are performed on the plurality of substrates respectively with the plurality of processing units in parallel based on recipe information corresponding to the lot.