Overlay Correction Control System for Semiconductor Fabrication
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current semiconductor fabrication methods face challenges in accurately correcting overlay errors between patterns on substrates, particularly due to non-correctable model parameters that hinder precise alignment and positioning in subsequent fabrication steps.
Innovation Solution
A method and system that involve forming patterns on substrates using multiple fabrication systems, obtaining overlay error profiles, and generating correction profiles to adjust positions before forming subsequent patterns, with a control system using a processor and memory to determine and correct non-correctable model parameters through preliminary correction profiles.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If overlay correction is performed using standard correction profiles, then overlay alignment between patterns is improved, but non-correctable model parameters cause residual errors that deteriorate manufacturing precision
Solution Approach 1:
The patent applies preliminary action by performing overlay correction in advance on the first fabrication system before the actual patterning process. The correction profile is generated and applied beforehand to compensate for non-correctable model parameters, ensuring that subsequent patterning operations start from a pre-corrected baseline, thereby eliminating residual alignment errors
Solution Approach 2:
The patent introduces an intermediary correction profile that acts as a mediator between the measured overlay error and the final correction applied to the second fabrication system. This correction profile translates raw measurement data into actionable correction parameters, filtering out non-correctable components and transmitting only the effective correction information to the control system
2Adaptability or versatility
If multiple fabrication systems are used to form patterns, then manufacturing flexibility is improved, but overlay errors between different systems increase due to system-specific variations
Solution Approach 1:
The patent implements universality by creating a standardized correction profile generation method that works across multiple different fabrication systems. The same correction methodology and measurement approach are applied universally to both the first and second fabrication systems, enabling consistent overlay correction regardless of which specific system is used, thereby maintaining manufacturing flexibility while ensuring precision
Solution Approach 2:
The patent applies feedback by measuring the actual overlay error between patterns formed on different fabrication systems and using this measurement information to generate corrective action. The measured overlay error feeds back into the correction profile generation process, creating a closed-loop system that continuously improves inter-system alignment based on actual performance data
3Manufacturing precision
If overlay error measurement and correction is performed for each substrate, then manufacturing precision is improved, but production time increases due to repeated measurements and corrections
Solution Approach 1:
The patent applies preliminary action by performing overlay error measurement and correction profile generation on a reference substrate before mass production. Once the correction profile is established from the reference substrate, it can be applied to subsequent substrates without repeating the full measurement and correction cycle, thereby maintaining substrate-level accuracy while improving throughput
Solution Approach 2:
The patent implements continuity of useful action by maintaining the correction profile across multiple substrate productions. Instead of interrupting production for repeated measurements, the correction information continues to be applied continuously to each substrate, keeping the useful correction action ongoing without interruption while ensuring consistent precision across all substrates
Data Source
AI summary
A method of correcting an overlay includes: forming a first pattern on a first substrate; forming a second pattern on the first pattern; obtaining a first overlay error profile of the second pattern and obtaining a first overlay correction profile from the first overlay error profile; forming a third pattern on the second pattern; obtaining a second overlay error profile of the third pattern and obtaining a second overlay correction profile from the second overlay error profile; and forming the second pattern on a second substrate, wherein the forming of the second pattern on the second substrate includes: determining whether the second overlay correction profile has a non-correctable model parameter; and when the second overlay correction profile has the non-correctable model, obtaining a preliminary correction profile to correct a position of the second pattern to be formed on the second substrate.