Lithography Mask Polygon Stitching for Boundary Continuity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current lithographic projection technologies face challenges in reproducing patterns with dimensions smaller than the classical resolution limit, particularly due to proximity effects and process window limitations, which can lead to manufacturing defects and reduced fidelity of the projected image to the intended design.
Innovation Solution
A method for determining a mask pattern by adjusting polygon portions at patch boundaries using a stitching function to reduce differences between adjacent feature patches, incorporating optical proximity correction and source optimization, and employing a level-set function to minimize discrepancies in curvilinear mask patterns.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the pattern is transferred using conventional lithographic projection, then the manufacturing process can be completed, but the fidelity of the projected image to the intended design deteriorates due to proximity effects and process window limitations
Solution Approach 1:
The patent applies preliminary action by pre-adjusting polygon portions at patch boundaries before the actual pattern transfer. The stitching function modifies the mask pattern in advance to compensate for expected discrepancies, ensuring that when the pattern is projected onto the substrate, the proximity effects are already accounted for and the fidelity is maintained.
Solution Approach 2:
The patent employs parameter changes by modifying the geometric parameters of polygon portions at patch boundaries. The stitching function adjusts coordinates, positions, and shapes of these portions to optimize the pattern transfer, thereby changing the parameters to overcome proximity effects and improve manufacturing precision.
2Device complexity
If the mask pattern is divided into multiple patches for processing, then the computational complexity is reduced, but step or jump differences appear at patch boundaries
Solution Approach 1:
The patent extracts the boundary regions from the overall mask pattern processing and applies a specialized stitching function specifically to these extracted portions. By isolating and separately processing the polygon portions at patch boundaries, the method addresses the continuity issue without complicating the processing of the entire pattern.
Solution Approach 2:
The stitching function acts as an intermediary between adjacent patches. It mediates the transition at patch boundaries by adjusting polygon portions to eliminate steps or jumps, thereby ensuring continuity while allowing the patches to be processed independently with reduced computational complexity.
3Manufacturing precision
If the polygon portions at patch boundaries are adjusted using stitching function, then the difference between adjacent patches is reduced, but the processing time increases
Solution Approach 1:
The patent applies local quality by focusing the stitching function adjustments only on polygon portions at patch boundaries rather than the entire mask pattern. This localized approach reduces the difference at boundaries while minimizing the additional processing time required, as only specific regions are modified rather than the complete pattern.
Data Source
AI summary
A method for generating a mask pattern to be employed in a patterning process. The method including obtaining (i) a first feature patch including a first polygon portion of an initial mask pattern, and (ii) a second feature patch including a second polygon portion of the initial mask pattern; adjusting the second polygon portion at a patch boundary between the first feature patch and the second feature patch such that a difference between the first polygon portion and the second polygon portion at the patch boundary is reduced; and combining the first polygon portion and the adjusted second polygon portion at the patch boundary to form the mask pattern.