In-Line Metrology for Substrate Thickness Monitoring
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional optical metrology systems in substrate polishing processes require substrates to be stationary or moved between separate modules, which reduces throughput and increases the footprint of the polishing system, as they are typically positioned inside a factory interface unit and require additional time for substrate handling.
Innovation Solution
Integrating in-line optical metrology systems within the substrate cleaning and drying modules, allowing for real-time thickness measurement of substrates as they are moved between cleaning and drying stages, thereby eliminating the need for additional handling and reducing the system's footprint by positioning metrology stations inside the cleaning system housing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If optical metrology systems are positioned inside a factory interface unit and require substrate to be stationary or moved between separate modules, then measurement can be performed, but throughput is reduced and system footprint is increased
Solution Approach 1:
The patent merges the optical metrology system with the cleaning and drying modules by integrating the metrology station inside the cleaning system housing. The substrate is measured in-line during the cleaning process without requiring separate handling or stationary positioning, thus maintaining measurement precision while improving throughput by eliminating additional handling steps
Solution Approach 2:
The cleaning system housing is designed to serve multiple functions: it houses both the cleaning/drying modules and the optical metrology system. This multi-functional integration allows the substrate to be cleaned, dried, and measured within a single integrated system, reducing the need for separate modules and improving overall processing efficiency
2Measurement precision
If optical metrology systems are positioned inside a factory interface unit and require substrate to be stationary or moved between separate modules, then measurement can be performed, but system footprint is increased
Solution Approach 1:
The patent combines the metrology station with the cleaning system housing, allowing both functions to occupy the same physical space. This integration reduces the overall system footprint by eliminating the need for separate metrology module space while maintaining measurement capabilities
Solution Approach 2:
The cleaning system housing is designed as a multi-functional unit that accommodates both cleaning/drying operations and optical metrology measurements. This universal design reduces the total area required by the polishing system while providing both cleaning and measurement functions within the same footprint
3Productivity
If substrate is moved continuously through cleaning and drying modules, then throughput is maintained, but real-time thickness monitoring becomes difficult
Solution Approach 1:
The optical metrology system is designed to measure substrates in motion as they pass through the cleaning and drying modules. The system captures images at multiple positions along the substrate's path and processes them to determine thickness, enabling real-time monitoring without requiring the substrate to be stationary or slowing down the processing line
Solution Approach 2:
The system captures images of the substrate at multiple predetermined positions during its movement through the cleaning module. By pre-positioning the imaging stations and capturing data at optimal points during substrate traversal, the system ensures accurate thickness measurement is performed proactively as the substrate passes through, maintaining continuous throughput
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 integration enables continuous monitoring and measurement of substrate thickness during the cleaning and drying processes without impacting throughput, improving efficiency and reducing the physical space required for the polishing system.
Implementation Method 1
an optical train to direct light from the light source to the substrate at a non-zero incidence angle during scanning of the substrate and direct light reflected from the substrate to the line-scan camera
Data Source
AI summary
A substrate cleaning system includes a cleaner module to clean a substrate after polishing of the substrate, a drier module to dry the substrate after cleaning by the cleaner module, a substrate support movable along a first axis from a first position in the drier module to a second position outside the drier module, and an in-line metrology station including a line-scan camera positioned to scan the substrate as the substrate is held by the substrate support and the substrate support is between the first position to the second position. The first axis is substantially parallel to a face of the substrate as held in by the substrate support.