CMP Slurry Charged-Particle Removal for Wafer Damage Prevention

Solution Overview

Problem

Chemical mechanical planarization systems are susceptible to equipment failure and damage to semiconductor wafers due to debris and impurities during the CMP process, leading to increased costs and reduced yields.

Innovation Solution

An impurity removal system utilizing a charged particle separation process with electrodes and a power source to capture and remove positively and negatively charged ions and electrons from the slurry and cleaning fluids, preventing damage to wafers and equipment.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If chemical mechanical planarization is performed using slurry and cleaning fluids, then the semiconductor wafer surface is planarized, but debris and impurities in the fluids cause equipment failure and wafer damage

Engineering Contradiction:

Improvewafer surface planarityVSAvoidequipment reliability

Core Design Contradiction:

Manufacturing precisionVSReliability

Solution Approach 1:

The patent applies charged particle separation to remove debris and impurities from the slurry and cleaning fluids. By utilizing electrostatic forces to separate charged particles from the fluid, the system converts the harmful effect of debris into a beneficial purification process, preventing equipment failure while maintaining planarization quality

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

Solution Approach 2:

The patent introduces charged particle separation as an intermediary purification step between the planarization process and the wafer/equipment. This intermediary system removes harmful debris from the slurry and cleaning fluids, allowing the main planarization process to proceed without causing equipment failure or wafer damage

Inventive Principle:

Principle #24Intermediary (Mediator)

2Manufacturing precision

If chemical mechanical planarization is performed using slurry and cleaning fluids, then the semiconductor wafer surface is planarized, but debris and impurities in the fluids cause damage to semiconductor wafers

Engineering Contradiction:

Improvewafer surface planarityVSAvoidwafer damage from debris

Core Design Contradiction:

Manufacturing precisionVSObject-affected harmful factors

Solution Approach 1:

The patent applies charged particle separation to remove debris and impurities from the slurry and cleaning fluids. By utilizing electrostatic forces to separate charged particles from the fluid, the system converts the harmful effect of debris into a beneficial purification process, preventing equipment failure while maintaining planarization quality

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

Solution Approach 2:

The patent introduces charged particle separation as an intermediary purification step between the planarization process and the wafer/equipment. This intermediary system removes harmful debris from the slurry and cleaning fluids, allowing the main planarization process to proceed without causing equipment failure or wafer damage

Inventive Principle:

Principle #24Intermediary (Mediator)

3Reliability

If impurity removal system is added to CMP equipment, then wafer damage risk is reduced and equipment lifespan is extended, but system complexity increases

Engineering Contradiction:

Improveequipment reliabilityVSAvoidCMP system complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent replaces complex mechanical filtration systems with an electrostatic charged particle separation system. This substitution uses electrical fields rather than mechanical moving parts to remove impurities, simplifying the overall system while maintaining high reliability and effective debris removal

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent changes the operational parameters of the CMP system by introducing electrostatic separation based on electrical charge properties of particles. This parameter change allows for selective removal of charged debris from the slurry and cleaning fluids without requiring complex mechanical separation equipment

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 impurity removal system effectively reduces the risk of wafer damage and extends the lifespan of CMP equipment by removing debris and impurities, thereby increasing semiconductor wafer yields and minimizing the need for repairs or replacements.

Implementation Method 1

An impurity removal system utilizing a charged particle separation process with electrodes and a power source to capture and remove positively and negatively charged ions and electrons from the slurry and cleaning fluids

Methodology Applied

Scientific EffectCharged particle separation: Electrophoresis

Data Source

PatentUS20240412977A1System and method for removing impurities during chemical mechanical planarization

Publication Date: 2024.12.12 TAIWAN SEMICONDUCTOR MANUFACTURING CO LTD

AI summary

A chemical mechanical planarization system includes a chemical mechanical planarization pad that rotates during a chemical mechanical planarization process. A chemical mechanical planarization head places a semiconductor wafer in contact with the chemical mechanical planarization pad during the process. A slurry supply system supplies a slurry onto the pad during the process. A pad conditioner conditions the pad during the process. An impurity removal system removes debris and impurities from the slurry.