Copper CMP Polishing Composition for Low Dishing and Corrosion

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

The challenge in chemical-mechanical polishing (CMP) processes is achieving a high removal rate of copper while minimizing dishing and corrosion, particularly due to excessive mechanical and chemical aggression, which affects the integrity and flatness of semiconductor wafers.

Innovation Solution

A polishing composition comprising abrasives, a first corrosion inhibitor with phosphate or phosphonate groups, a complexing agent, and a second corrosion inhibitor with azole compounds, balanced to achieve controlled copper removal with minimal dishing and corrosion, using a combination of additives to regulate the dissolution of copper oxides.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If high down force is used in initial Cu bulk polishing step to achieve high removal rate, then productivity is improved, but dishing occurs due to excessive mechanical aggression

Engineering Contradiction:

Improveremoval rateVSAvoiddishing

Core Design Contradiction:

ProductivityVSManufacturing precision

Solution Approach 1:

The patent uses corrosion inhibitors (phosphate/phosphonate and azole compounds) to chemically modify the polishing interface, changing the effective aggressiveness parameters of the polishing system without altering mechanical down force, thereby achieving high removal rates with reduced dishing

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The corrosion inhibitors act as intermediary substances between the copper surface and the polishing slurry, forming protective complexes that moderate the chemical etching action during overpolishing, reducing dishing while maintaining removal efficiency

Inventive Principle:

Principle #24Intermediary (Mediator)

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 composition effectively removes copper with low dishing and corrosion, maintaining wafer quality by forming a protective passivation film that balances copper removal rates and surface protection.

Implementation Method 1

forming a protective passivation film that balances copper removal rates and surface protection

Methodology Applied

Scientific EffectPassivation:

Implementation Method 2

continued chemical etching of the Cu lines due to continued contact with the polishing composition throughout the overpolishing

Methodology Applied

Scientific EffectChemical etching: Solvation

Implementation Method 3

the electro-plated copper overburden is rapidly polished down at a relatively high down force

Methodology Applied

Scientific EffectAbrasion: Abrasion

Data Source

PatentUS12398291B2Polishing compositions and methods of use thereof

Publication Date: 2025.08.26 FUJIFILM ELECTRONIC MATERIALS U S A INC

AI summary

This disclosure features a polishing composition that includes at least one abrasive; at least one first corrosion inhibitor that includes a phosphate or a phosphonate group; at least one complexing agent; at least one second corrosion inhibitor that is at least one azole compound; and optionally a pH adjuster.