Variance Components Analysis for Total Measurement Uncertainty
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current process control methods in manufacturing environments, particularly in semiconductor manufacturing, lack alignment between semiconductor manufacturers and tool manufacturers, leading to inadequate monitoring of measurement variation, which can result in reduced product quality and increased costs due to poor process control.
Innovation Solution
A system and method that utilize variance components analysis to calculate total measurement uncertainty (TMU) and TMU control limit impact (CLI) from production data, allowing for continuous monitoring and adjustment of manufacturing and metrology tools to ensure consistent tool performance and reduce measurement uncertainty.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional monitoring methods are used separately by semiconductor manufacturers and tool manufacturers, then each party can maintain their own measurement standards, but alignment between parties is lost and overall measurement uncertainty increases
Solution Approach 1:
The patent combines separate monitoring systems into a unified variance components analysis framework that processes data from multiple tools and manufacturers together, creating a single integrated system that reduces measurement uncertainty while managing complexity through standardized statistical methods
Solution Approach 2:
The monitoring system is designed to be universal, handling data from different tool types and manufacturers through a common statistical framework that can accommodate various measurement scenarios while maintaining consistent quality standards across the entire manufacturing ecosystem
2Reliability
If all production manufacturing data is used for monitoring, then comprehensive process control is achieved, but it becomes difficult to separate measurement variation from process variation
Solution Approach 1:
The patent segments total variation into distinct components using variance components analysis, separating measurement system variation from process variation by analyzing different sources of variability in the production data, thereby enabling reliable process control while clearly identifying variation sources
Solution Approach 2:
The variance components analysis acts as an intermediary statistical framework that processes comprehensive production data and decomposes it into separable variation components, allowing the system to maintain reliability while solving the difficulty of source identification through structured statistical mediation
3Measurement precision
If reference wafer matching studies are performed, then measurement tool health can be monitored, but the method does not scale with production volume and alarm percentages do not increase appropriately
Solution Approach 1:
The patent implements continuous monitoring using production data that naturally occurs during normal manufacturing operations, eliminating the need for separate reference wafer studies and enabling the system to scale efficiently with production volume while maintaining consistent tool health monitoring capability
Solution Approach 2:
The monitoring system uses the production data that already exists from normal operations to automatically assess tool health, making the system self-sufficient without requiring additional reference materials or separate testing procedures, thereby improving productivity while maintaining measurement precision
Data Source
AI summary
A process control technique uses production data from multiple manufacturing tools and multiple inspection or metrology tools. Total measurement uncertainty (TMU) can be calculated on the production data, which can include measurements of one or more devices manufactured using the manufacturing tools. Manufacturing steps can be ranked or otherwise compared by TMU. All production modes and recipes can be continually monitored using production data.