CMP Wafer Cleaning Brush Agitation Transducer

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing methods for cleaning semiconductor wafers after the Chemical Mechanical Polishing (CMP) process are inadequate in efficiently removing polishing slurry and residues without introducing additional defects or damage, leading to yield reduction due to contamination accumulation on cleaning brush members.

Innovation Solution

The implementation of a cleaning system that includes a cleaning brush assembly with a rotation shaft and a brush member, where an agitation transducer produces an agitated cleaning liquid to effectively remove contaminants from the brush member, ensuring thorough cleaning and preventing yield reduction.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional cleaning methods are used to remove polishing slurry and residues, then cleaning capability is maintained, but contamination accumulation on brush members occurs leading to yield reduction

Engineering Contradiction:

ImproveyieldVSAvoidcontamination accumulation

Core Design Contradiction:

ReliabilityVSObject-generated harmful factors

Solution Approach 1:

An agitation transducer is integrated into the cleaning brush assembly to generate ultrasonic vibrations in the cleaning liquid and brush members. This mechanical vibration creates cavitation and enhances the mechanical action of cleaning, effectively removing polishing slurry and residues from the wafer surface and preventing contamination accumulation on the brush members, thereby maintaining yield

Inventive Principle:

Principle #18Mechanical vibration

Solution Approach 2:

The cleaning system changes the physical state and properties of the cleaning liquid by applying ultrasonic energy, creating an agitated cleaning liquid with enhanced cleaning properties. This parameter change in the cleaning liquid's agitation state improves its ability to remove contaminants without causing damage to the wafer or accumulating on the brush members

Inventive Principle:

Principle #35Parameter changes

2Productivity

If cleaning brush members are used continuously to clean wafers, then productivity is maintained, but cleaning effectiveness degrades due to contamination accumulation

Engineering Contradiction:

ImprovethroughputVSAvoidcleaning effectiveness

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The agitation transducer operates continuously during the cleaning process to maintain constant agitation of the cleaning liquid and brush members. This continuous action ensures that cleaning effectiveness is maintained throughout the entire cleaning cycle, preventing contamination accumulation that would otherwise degrade performance over time while sustaining high productivity

Inventive Principle:

Principle #20Continuity of useful action

Solution Approach 2:

Ultrasonic vibrations are applied continuously to the cleaning liquid and brush members during wafer cleaning, maintaining the cleaning mechanism's effectiveness throughout continuous operation. This prevents the degradation of cleaning performance that would normally occur with continuous use, allowing sustained high throughput

Inventive Principle:

Principle #18Mechanical vibration

3Manufacturing precision

If aggressive cleaning methods are used to remove all residues, then cleaning completeness is improved, but damage to substrate surface may occur

Engineering Contradiction:

Improvecleaning completenessVSAvoidsubstrate surface damage

Core Design Contradiction:

Manufacturing precisionVSObject-affected harmful factors

Solution Approach 1:

Ultrasonic vibrations provide gentle yet effective cleaning action through cavitation and micro-jetting effects, removing polishing slurry and residues complete without requiring aggressive mechanical forces. This achieves thorough cleaning completeness while preventing damage to the delicate substrate surface

Inventive Principle:

Principle #18Mechanical vibration

Solution Approach 2:

The cleaning liquid is transformed into an agitated state with enhanced cleaning properties through ultrasonic energy, allowing complete removal of residues at lower mechanical stresses. This parameter change enables achieving cleaning completeness without the substrate surface damage that would result from aggressive mechanical cleaning methods

Inventive Principle:

Principle #35Parameter changes

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 agitated cleaning liquid efficiently cleans the brush members, maintaining their effectiveness and reducing yield loss by preventing contamination accumulation, thereby increasing the overall throughput and prolonging the lifespan of cleaning components.

Implementation Method 1

an agitation transducer produces an agitated cleaning liquid to effectively remove contaminants from the brush member

Methodology Applied

Scientific EffectUltrasonic vibration: Ultrasonic Vibration

Data Source

PatentUS11446712B2System for cleaning wafer in CMP process of semiconductor manufacturing fabrication

Publication Date: 2022.09.20 TAIWAN SEMICONDUCTOR MANUFACTURING CO LTD

AI summary

A system for performing a Chemical Mechanical Polishing (CMP) process is provided. The system includes a CMP module configured to polish a semiconductor wafer. The system further includes a cleaning brush assembly configured to clean the semiconductor wafer. The cleaning brush includes a rotation shaft and a brush member surrounding a segment of the rotation shaft. The system also includes an agitation transducer arranged to be distant from the brush member and configured to produce an agitated cleaning liquid to clean the cleaning brush assembly.