Substrate Holder Position Correction Using Dual Deviation Measurement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing substrate transfer systems face challenges in accurately transferring substrates due to thermal expansion and model errors, leading to misalignment and reduced precision in positioning.
Innovation Solution
A substrate transfer method that utilizes a substrate transfer system with measurement parts to calculate true deviation amounts at different positions, reflects differences in a physical model to correct for thermal displacement, and adjusts the transfer mechanism to achieve precise positioning by averaging model errors and using error factors to refine thermal displacement estimates.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If thermal displacement correction is performed using a physical model, then positioning accuracy is improved, but model errors reduce the correction precision
Solution Approach 1:
The patent implements feedback by measuring the actual substrate position with a measurement part, calculating the deviation from the target position, and using this measured deviation to correct the physical model. The correction amount is derived from the difference between measured position and model-predicted position, creating a closed-loop system that continuously improves accuracy based on actual performance data.
Solution Approach 2:
The patent replaces reliance on purely theoretical mechanical models with actual measurement data. Instead of depending solely on the physical model's mathematical predictions of thermal expansion, the system substitutes model predictions with empirically measured positions from the measurement part, thereby eliminating model errors from the correction calculation.
2Measurement precision
If multiple measurement parts are used to measure substrate position at different positions, then thermal expansion correction is improved, but system complexity increases
Solution Approach 1:
The patent divides the measurement function into multiple measurement parts positioned at different locations along the substrate transfer path. Each measurement part measures thermal expansion at its specific position, allowing the system to capture temperature-induced dimensional changes at multiple points. This segmented measurement approach enables more accurate thermal expansion correction without requiring a single complex measurement system.
Solution Approach 2:
The patent introduces measurement parts as intermediary elements between the substrate and the control system. These measurement parts act as mediators that convert physical thermal expansion into measurable signals, which are then processed to calculate correction amounts. The measurement parts serve as intermediaries that bridge the gap between thermal physical phenomena and digital control corrections.
3Measurement precision
If substrate position is measured at multiple positions, then transfer accuracy is improved, but measurement time increases
Solution Approach 1:
The patent performs preliminary measurements by positioning measurement parts along the substrate transfer path before actual substrate transfer occurs. The system pre-establishes measurement reference points and calculates thermal expansion characteristics in advance, allowing rapid correction during actual transfer operations without requiring time-consuming measurements during production cycles.
Solution Approach 2:
The patent implements continuous measurement capability where multiple measurement parts simultaneously monitor substrate position throughout the transfer process. Instead of sequential measurements that would interrupt transfer, the system maintains continuous positional awareness through parallel measurement at multiple locations, eliminating measurement time from the critical transfer path.
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 method enhances the accuracy of substrate transfer by correcting for thermal expansion and model errors, ensuring precise positioning and improved transfer accuracy.
Implementation Method 1
a first measurement part configured to measure a position of the substrate at a first measurement position adjacent to the first stage, and a second measurement part configured to measure the position of the substrate at a second measurement position
Implementation Method 2
a substrate transfer mechanism provided with a holder configured to hold the substrate and configured to transfer the substrate from a first stage to the second stage
Data Source
AI summary
A method includes: receiving a substrate on a first stage by a holder of a substrate transfer mechanism; causing the substrate to pass through a first measurement part, and measuring a first true deviation amount between the holder and the substrate at a first position; causing, when transferring the substrate toward a second stage, the substrate to pass through a second measurement part, and measuring a second true deviation amount between the holder and the substrate at a second position; reflecting a difference between the first and second true deviation amounts to a physical model to correct the physical model; calculating a position correction amount of the holder on the second stage from a thermal displacement amount of the holder at the second position; and controlling the substrate transfer mechanism based on the position correction amount to perform a position correction of the holder.