Imprint Alignment Correction via Baseline and Feedback
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In imprint techniques, the die-by-die method for aligning substrates with molds is time-consuming and decreases productivity due to the need for post-process testing and frequent alignment adjustments, while the global alignment method, although more productive, requires stable and accurate detection of baseline positions to maintain overlay accuracy.
Innovation Solution
An imprint apparatus that uses a scope to observe marks on both the substrate and mold, with a controller that detects displacement and corrects it by remeasuring the baseline amount or reexecuting the global alignment process if the displacement exceeds an allowable range, ensuring accurate pattern transfer across multiple shots.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the die-by-die method is used for alignment, then overlay accuracy is maintained through frequent measurement and correction, but productivity decreases due to time-consuming alignment adjustments and post-process testing
Solution Approach 1:
The patent performs baseline measurement before the global alignment process to establish reference positions. This preliminary action allows the system to pre-calculate alignment parameters for all shots, eliminating the need for frequent measurements during production and enabling high-speed molding while maintaining accuracy
Solution Approach 2:
The patent implements a feedback mechanism where the scope measures actual positions during molding, compares them with baseline data, and automatically corrects deviations. This closed-loop control maintains overlay accuracy without requiring manual intervention or post-process testing for each shot
2Productivity
If the global alignment method is used for molding, then productivity increases by reducing alignment adjustments and post-process testing, but overlay accuracy deteriorates due to position changes from pressing forces
Solution Approach 1:
The patent compensates for expected position changes caused by pressing forces by incorporating correction terms into the alignment calculation. The system predicts displacement due to mold pressing and pre-adjusts the alignment parameters, cushioning against accuracy deterioration before it occurs
Solution Approach 2:
The scope continuously monitors actual positions during the molding process and provides feedback to the controller. When position deviations exceed predetermined thresholds, the system automatically triggers re-measurement and re-calculation of alignment parameters, maintaining accuracy throughout high-speed production
3Manufacturing precision
If baseline measurement is performed frequently to maintain accuracy, then overlay precision is improved, but productivity decreases due to increased measurement time
Solution Approach 1:
The system performs comprehensive baseline measurement once before the global alignment process, establishing reference data for all shots. This single preliminary measurement replaces the need for frequent repeated measurements, saving time while maintaining accuracy through the feedback mechanism that detects and corrects deviations
Solution Approach 2:
The patent introduces marks as intermediary reference elements that are measured by the scope. These marks serve as stable reference points that enable accurate position detection without requiring direct measurement of the mold-substrate interface, reducing measurement time while maintaining precision
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
This approach enhances productivity by allowing real-time correction of displacement, maintaining pattern accuracy, and reducing the need for extensive post-process testing, thereby improving the efficiency and quality of pattern transfer in mass-producing semiconductor devices.
Implementation Method 1
a scope for observing a mark formed in each shot of the substrate and a mark formed on the mold
Implementation Method 2
the controller performs the observation by the scope, detects an amount of displacement of the shot with respect to the mold based on the observation result
Implementation Method 3
The photo-curing method forms a pattern by pressing a mold against a substrate with an ultraviolet-curing resin being sandwiched between them, curing the resin by irradiating it with ultraviolet light
Data Source
AI summary
An imprint apparatus comprises a scope which observes a mark formed in each shot of a substrate and a mark formed on a mold and a controller. The controller performs observation by the scope, detects an amount of displacement of the shot with respect to the mold based on the observation result, and, if the detected displacement amount falls outside an allowable range, executes at least one of remeasuring a baseline amount and reexecuting a global alignment process.