Embedded Sensor Measurement Substrate for Lithography
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current measurement substrates used in lithographic apparatuses, such as thermal test substrates, do not provide sufficient accuracy to predict thermal distortion and overlay errors effectively, especially in EUV lithography, due to limitations in temperature and strain measurement capabilities.
Innovation Solution
A measurement substrate with embedded sensor modules and a central control module, featuring temperature and strain sensors, analog to digital converters, and amplifiers, designed to generate and convert analog measurement signals into digital data for precise temperature and strain measurements, reducing noise interference and enhancing data accuracy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional thermal test substrates are used for measurement, then the apparatus can perform basic thermal monitoring, but the measurement precision and accuracy are insufficient to predict thermal distortion and overlay errors effectively
Solution Approach 1:
The measurement substrate is divided into multiple sensor modules distributed across the substrate surface. Each module contains temperature sensors and strain sensors that independently measure local conditions. This segmentation allows for high-resolution spatial mapping of thermal and mechanical fields without requiring a single complex centralized measurement system.
Solution Approach 2:
The measurement substrate employs a composite structure combining the production substrate material with embedded sensor elements. Temperature sensors and strain sensors are integrated into the substrate matrix, creating a composite material system that maintains the optical and thermal properties of the original substrate while adding measurement capabilities. This approach avoids the need for separate measurement apparatus.
2Measurement precision
If multiple sensor modules with analog to digital converters are embedded in the substrate, then measurement precision and noise reduction are improved, but the device complexity and manufacturing difficulty increase
Solution Approach 1:
Multiple functional elements are merged into integrated sensor modules: temperature sensors, strain sensors, analog to digital converters, and signal processing circuitry are combined in single modular units. This integration reduces the number of discrete components that need to be manually assembled and simplifies the manufacturing process while maintaining high measurement precision.
Solution Approach 2:
Analog signal processing and conversion are replaced with digital processing through embedded analog to digital converters. This substitution eliminates the need for complex external analog signal conditioning circuitry and reduces susceptibility to electromagnetic interference, thereby improving signal accuracy while simplifying the overall system architecture.
3Reliability
If embedded sensors and control modules are added to the substrate, then the ability to predict thermal distortion and overlay errors is improved, but the substrate complexity and potential sources of error increase
Solution Approach 1:
The measurement substrate incorporates real-time feedback through embedded controllers that continuously monitor temperature and strain measurements. The controllers process sensor data and provide feedback signals that can be used to adjust processing conditions or predict thermal distortion before it affects overlay accuracy. This closed-loop feedback mechanism improves prediction reliability while keeping the added complexity manageable.
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
The solution enables accurate and precise measurement of temperature and strain changes during lithographic processes, improving the prediction of thermal distortion and overlay errors, thereby supporting the imaging of smaller features and meeting stricter overlay error limits.
Implementation Method 1
Each sensor module comprises: a sensor configured to generate an analog measurement signal
Implementation Method 2
a sensor configured to generate an analog measurement signal, the sensor comprising at least a temperature sensor or a strain sensor
Implementation Method 3
an analog to digital converter configured to generate digital measurement information from the analog measurement signal
Data Source
AI summary
A measurement substrate for measuring a condition pertaining in an apparatus for processing production substrates during operation thereof, the measurement substrate including: a body having dimensions compatible with the apparatus; a plurality of sensor modules embedded in the body, each sensor module having: a sensor configured generate an analog measurement signal, an analog to digital converter to generate digital measurement information from the analog measurement signal, and a module controller configured to output the digital measurement information; and a central control module configured to receive the digital measurement information from each of the module controllers and to communicate the digital measurement information to an external device.