Polishing Composition for Group III-V Compound Substrates

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The existing methods for polishing semiconductor substrates with Group III-V compounds suffer from excessive etching, leading to recesses and reduced polishing speed, particularly when using high mobility materials like GaAs.

Innovation Solution

A polishing composition comprising abrasive grains, an oxidizer, and an anionic surfactant is used to form a hydrophobic film on the oxide layer of Group III-V compounds, inhibiting etching and allowing for high-speed polishing by facilitating the removal of the brittle oxide film.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If conventional polishing methods are used on Group III-V compounds, then polishing can be performed, but excessive etching occurs leading to recesses and reduced polishing speed

Engineering Contradiction:
Improvepolishing speedVSAvoidsurface flatness
Core Design Contradiction:
ProductivityVSManufacturing precision

Solution Approach 1:

The invention changes the chemical composition parameters of the polishing slurry by incorporating specific oxidizers (potassium permanganate, sodium persulfate, hydrogen peroxide) and anionic surfactants (lauryl phosphate, polyoxyethylene lauryl ether phosphoric acid) in controlled concentrations. This chemical parameter modification enables high-speed polishing while suppressing excessive etching and recess formation on Group III-V compound surfaces

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The anionic surfactant acts as an intermediary substance that mediates between the oxidizer and the Group III-V compound surface. It forms a protective layer that controls the oxidation process, preventing excessive etching while maintaining efficient material removal for high-speed polishing

Inventive Principle:
Principle #24Intermediary (Mediator)

2Productivity

If high polishing speed is achieved on high mobility material portions, then processing efficiency improves, but etching increases causing level differences on the surface

Engineering Contradiction:
Improvepolishing speedVSAvoidetching and level difference
Core Design Contradiction:
ProductivityVSObject-affected harmful factors

Solution Approach 1:

The invention modifies the chemical parameters of the polishing environment by controlling oxidizer concentration (0.1-10 g/L) and surfactant concentration (0.01-5 g/L), creating optimal conditions that enable high polishing speed while suppressing harmful etching effects that cause level differences

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The invention converts the potentially harmful etching effect into a beneficial controlled oxidation process. The oxidizer and surfactant combination transforms aggressive material removal into a controlled process that removes material at high speed while maintaining surface integrity and preventing level differences

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

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 suppresses etching and enhances polishing speed while maintaining high selectivity, reducing the generation of recesses and improving the surface finish of semiconductor substrates.

Implementation Method 1

contains an anionic surfactant... forms a hydrophobic film on the oxide layer... inhibiting etching

Methodology Applied
Scientific EffectHydrophobic film formation: Hydrophobe

Implementation Method 2

a polishing composition comprising abrasive grains, an oxidizer, and an anionic surfactant

Methodology Applied
Scientific EffectSurfactant action: Surfactant

Implementation Method 3

an oxidizer... form a hydrophobic film on the oxide layer

Methodology Applied
Scientific EffectOxidation: Oxidation

Implementation Method 4

abrasive grains... removal of the brittle oxide film

Methodology Applied
Scientific EffectAbrasion: Abrasion

Data Source

PatentUS10759969B2Polishing composition, polishing method, and method for manufacturing semiconductor substrate
Publication Date: 2020.09.01 FUJIMI INCORPORATED

AI summary

The present invention provides a polishing composition which is suitable for polishing an object to be polished having a layer containing a Group III-V compound, suppresses etching of the Group III-V compound, and is capable of polishing at a high polishing speed. The polishing composition according to the present invention is a polishing composition used for polishing an object to be polished having a layer containing a Group III-V compound and contains abrasive grains, an oxidizer, and an anionic surfactant.