Rotating-Ball Brush Nodules for Low-Damage Wafer Cleaning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wafer cleaning processes using brushes result in contamination and damage to semiconductor wafers due to polishing residues and excessive contact pressure, leading to reverse contamination and reduced brush lifespan.
Innovation Solution
A brush design featuring nodules with rotating balls housed in open-sided structures that minimize contact ratio and apply pressure uniformly, reducing damage and extending brush life while effectively removing residues.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a brush is used to clean polishing residues from the wafer surface, then cleaning effectiveness is improved, but reverse contamination and wafer damage occur due to polishing residues transferring from the brush to the wafer
Solution Approach 1:
The brush nodules incorporate rotating balls that dynamically adjust their rotation based on contact with the wafer surface. This dynamic motion prevents polishing residues from being transferred back to the wafer while maintaining effective cleaning action, thereby resolving the reverse contamination issue without sacrificing cleaning effectiveness
Solution Approach 2:
The rotating balls in the brush nodules perform periodic rotation as they contact the wafer surface. This periodic motion creates a cleaning action that continuously removes residues while preventing their transfer to the wafer, addressing both cleaning effectiveness and reverse contamination concerns
2Productivity
If brush contact pressure is increased to improve cleaning effectiveness, then polishing residues are removed more effectively, but wafer surface damage such as scratches increases
Solution Approach 1:
The brush design implements local quality by creating nodules with rotating balls that concentrate cleaning action at specific contact points. This localized approach allows effective residue removal at the nodule-wafer interface while distributing overall pressure, preventing excessive contact pressure and surface damage across the wafer
Solution Approach 2:
The rotating balls dynamically adapt to the wafer surface topology, concentrating force where needed for effective cleaning while naturally distributing pressure to avoid excessive contact. This dynamic pressure distribution maintains cleaning effectiveness without causing surface damage
3Productivity
If brush contact area with wafer is increased to improve cleaning coverage, then cleaning efficiency is improved, but brush consumption increases and brush lifespan is reduced
Solution Approach 1:
The brush is segmented into multiple nodules, each containing a rotating ball. This segmentation allows the cleaning function to be distributed across many small contact points rather than a large continuous contact area. The rotating balls in each nodule can be independently replaced or rotated, extending overall brush lifespan while maintaining high cleaning efficiency through parallel action of multiple nodules
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 minimizes wafer damage and extends brush replacement cycles by optimizing contact and pressure distribution, enhancing cleaning efficiency and reducing contamination risks.
Implementation Method 1
The rotating ball is rotatable... minimizing contact ratio and apply pressure uniformly, reducing damage
Data Source
AI summary
A brush includes a body, and a plurality of nodules disposed on at least one surface of the body and at least partially protruding outward from the body. The plurality of nodules include a plurality of first nodules. Each nodule of the plurality of first nodules includes a housing including an open side and an accommodating space, and a rotating ball including a portion accommodated inside the accommodating space of the housing and a remaining portion exposed to an outside of the housing. The rotating ball is rotatable.