Quaternary Ammonium Hydroxide Cleaning Composition for Semiconductor Residues

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing cleaning agents are ineffective in removing difficult-to-remove organic/inorganic residues from semiconductor processing surfaces, particularly after harsh processing steps like high-temperature baking or ion implantation, as these residues become insoluble in common organic solvents.

Innovation Solution

A composition comprising a quaternary ammonium hydroxide with specific structural formulas and a dipolar aprotic solvent, substantially free of water, is applied to the surface to effectively remove residues, including post-bake residues and ion-implanted polymeric materials, without the need for protic solvents or water.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If traditional quaternary ammonium hydroxides (like TMAH) are used for cleaning, then cleaning action is provided, but water content and solubility issues arise making them less effective

Engineering Contradiction:

Improvecleaning effectivenessVSAvoidwater content

Core Design Contradiction:

ReliabilityVSQuantity of substance

Solution Approach 1:

The patent changes the chemical structure parameters of the quaternary ammonium compound by introducing specific hydrophobic groups (aryl, arylalkyl, or heteroaryl substituents) and adjusting the alkyl chain lengths (C1-C6), thereby modifying the solubility and water content characteristics while maintaining cleaning effectiveness

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The invention creates a composite cleaning system combining the quaternary ammonium hydroxide with specific hydrophobic groups and alkyl chains, forming a novel compound structure that integrates both cleaning capability and improved solubility characteristics without water

Inventive Principle:

Principle #40Composite materials

2Manufacturing precision

If harsh processing steps (high-temperature bake, ion implantation) are applied to modify surfaces, then desired surface properties are achieved, but residues become insoluble and difficult to remove

Engineering Contradiction:

Improvesurface modification qualityVSAvoidresidue removal difficulty

Core Design Contradiction:

Manufacturing precisionVSEase of manufacture

Solution Approach 1:

The patent modifies the chemical parameters of the cleaning agent by introducing hydrophobic aromatic groups and optimizing alkyl chain lengths, enabling the cleaner to effectively solubilize and remove residues created by harsh processing steps that would otherwise be insoluible

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The invention applies the cleaning composition specifically to residue-containing areas after harsh processing, with the quaternary ammonium compound's hydrophobic groups providing localized effective action on the insoluble residues while maintaining overall cleaning system performance

Inventive Principle:

Principle #3Local quality

3Reliability

If organic solvents are used to remove polymer residues, then some cleaning is achieved, but strongly alkaline components are required which have limitations

Engineering Contradiction:

Improveresidue removal capabilityVSAvoidsolvent compatibility

Core Design Contradiction:

ReliabilityVSAdaptability or versatility

Solution Approach 1:

The patent changes the fundamental chemical parameters by using quaternary ammonium hydroxide with hydrophobic groups that can function in both organic and aqueous environments, providing versatile cleaning capability across different solvent systems without requiring strongly alkaline components

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The quaternary ammonium compound with hydrophobic groups provides universal cleaning effectiveness across multiple solvent types and application conditions, making the cleaner adaptable to various residue types and processing histories without being limited to strongly alkaline environments

Inventive Principle:

Principle #6Universality (Multi-functionality)

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 provides a novel and effective method for removing hard-to-remove residues from semiconductor surfaces, enhancing cleaning efficiency while avoiding the limitations of traditional quaternary ammonium hydroxides like TMAH, such as water content and solubility issues.

Implementation Method 1

The quaternary ammonium hydroxide is soluble in dipolar aprotic solvents

Methodology Applied

Scientific EffectSolubility: Solvation

Implementation Method 2

applying to the surface a composition comprising: (a) a quaternary ammonium hydroxide... (b) a dipolar aprotic solvent... removing at least a substantial portion of the residue from the surface

Methodology Applied

Scientific EffectChemical cleaning:

Data Source

PatentUS9650595B2Quaternary ammonium hydroxides

Publication Date: 2017.05.16 SACHEM INC

AI summary

A composition including (a) a quaternary ammonium hydroxide having a general formula (I):as defined herein, and (b) a dipolar aprotic solvent substantially free of water.