Semiconductor Wafer Grouping for Feed Forward Process Variation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current semiconductor wafer processing techniques face challenges in balancing processing time and wafer-to-wafer variation, as Feed Forward (FFW) processes either increase process time with reduced variation or decrease time but increase variation.
Innovation Solution
A method involving acquiring process parameter measurements for each wafer, grouping them based on similar conditions, and processing in groups according to specific recipes, allowing for efficient processing while minimizing variation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a wafer-base mode is used where each wafer is assigned its own recipe and processed one-by-one, then wafer-to-wafer variation is decreased, but processing time is greatly increased
Solution Approach 1:
The patent segments wafers into groups based on similar process conditions rather than treating each wafer individually. This segmentation allows multiple wafers to be processed together in batches while still maintaining customized processing for each group, resolving the contradiction between individualized processing (low variation) and batch processing (high productivity).
Solution Approach 2:
The patent changes the parameter of processing organization from individual wafer-level to group-level based on process condition parameters. By clustering wafers with similar parameters together, the system achieves both efficient batch processing and tailored processing conditions, simultaneously improving productivity while maintaining manufacturing precision.
2Productivity
If a lot-base mode is used where the same recipe is applied to all wafers in a lot, then processing time is decreased, but wafer-to-wafer variation is increased
Solution Approach 1:
The patent applies local quality by assigning different recipes to different groups of wafers based on their specific process conditions. Instead of uniform treatment for all wafers in a lot, each group receives customized processing parameters tailored to its characteristics, thereby reducing wafer-to-wafer variation while maintaining batch processing efficiency.
Solution Approach 2:
The patent segments the lot into multiple groups with similar process conditions, allowing differentiated processing for each segment. This segmentation enables the system to achieve both the productivity benefits of batch processing and the precision benefits of customized processing for each group.
3Manufacturing precision
If multiple process jobs are created for each wafer in FFW process, then wafer-to-wafer variation is reduced, but the number of process jobs and process time increase
Solution Approach 1:
The patent merges multiple individual wafer process jobs into consolidated group process jobs. By combining wafers with similar process conditions into single process jobs, the system reduces the total number of process jobs while still maintaining customized processing for each group, thereby reducing process time without sacrificing manufacturing precision.
Data Source
AI summary
A method for processing a plurality of semiconductor wafers includes acquiring a process parameter measurement for each of the semiconductor wafers, associating each of the semiconductor wafers with one of a plurality of groups based on a respective process parameter measurement for each of the semiconductor wafers, where each respective group corresponds to a respective recipe, and for each one of the groups, processing ones of the semiconductor wafers associated with that group together according to a respective recipe.