Scanner Tool Aberration Mapping for Consistent Critical Dimensions

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Matching scanner tools in a production line to produce consistent critical dimensions (CD) without designating a single 'golden' scanner tool, which is costly, is challenging.

Innovation Solution

Adjusting Zernike coefficients to optimize aberration maps by altering the location and curvature of mirrors and lenses in scanner tools, allowing them to match each other's performance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If a golden scanner tool is designated as the reference for matching other scanner tools, then manufacturing precision (CD consistency) is improved, but device complexity and cost increase due to requiring a dedicated reference tool

Engineering Contradiction:

ImproveCD consistencyVSAvoidreference tool requirement

Core Design Contradiction:

Manufacturing precisionVSDevice complexity

Solution Approach 1:

The patent creates a virtual copy of the golden scanner tool's aberration map and uses it as a reference for matching other scanner tools. Instead of requiring a physical golden scanner tool to be maintained, the system copies the aberration characteristics digitally and compares other tools against this copied reference, eliminating the need for a dedicated physical reference tool while maintaining matching accuracy

Inventive Principle:

Principle #26Copying

Solution Approach 2:

The patent replaces the mechanical/physical reference system (golden scanner tool) with a computational/optical system. By substituting the physical golden scanner with a digitally stored aberration map and using optical wavefront sensing to measure and compare other scanners, the system eliminates the need for maintaining a dedicated reference scanner while achieving the same matching function

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Productivity

If multiple scanner tools are used in a production line, then productivity is improved, but manufacturing precision deteriorates due to CD variations between different tools

Engineering Contradiction:

Improveproduction line capacityVSAvoidCD variation

Core Design Contradiction:

ProductivityVSManufacturing precision

Solution Approach 1:

The patent measures and adjusts the aberration parameters (Zernike coefficients) of each scanner tool's optical system to match the reference aberration map. By changing the optical parameters of individual scanners through mirror adjustments, the system enables multiple tools to produce consistent CD measurements while maintaining high productivity through parallel production capability

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent implements a feedback mechanism where each scanner tool's aberration map is measured and compared against the reference, and adjustments are made based on the deviation. This closed-loop feedback process ensures that CD variations between multiple scanner tools are minimized while allowing the production line to operate with multiple parallel tools

Inventive Principle:

Principle #23Feedback

Data Source

PatentUS12416864B2Tool mismatch reduction using aberration map of the tools

Publication Date: 2025.09.16 TAIWAN SEMICONDUCTOR MANUFACTURING CO LTD

AI summary

In a method of tool matching, aberration maps of two or more optical systems of two or more scanner tools are determined. A photoresist pattern is generated by projecting a first layout pattern by an optical system of each one of the two or more scanner tools on a respective substrate. One or more Zernike coefficients of the two or more optical systems are adjusted based on the determined aberration maps of the two or more optical systems to minimize critical dimension (CD) variations in a first region of the photoresist patterns on each respective substrate.