Ozone Water Cleaning Semiconductor Substrates

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

The half-life period of ozone in ultra-pure ozone water used for cleaning semiconductor substrates is significantly shorter than in conventional ozone water, leading to reduced cleaning performance due to ozone concentration depletion, primarily caused by ultraviolet ray-induced organic carbon decomposition.

Innovation Solution

Adding a trace amount of an organic solvent, such as ethanol or isopropyl alcohol, to the ultra-pure ozone water using a porous polymer membrane to extend the ozone half-life period while preventing organic carbon residue on the substrate.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If ultra-pure water is used for cleaning semiconductor substrates, then cleaning quality is improved, but ozone half-life period is significantly shortened

Engineering Contradiction:

Improvecleaning qualityVSAvoidozone half-life period

Core Design Contradiction:

Manufacturing precisionVSDuration of action of stationary object

Solution Approach 1:

The invention changes the chemical composition parameter of the cleaning solution by adding a small amount of organic solvent (0.01-10 ppm) to ultra-pure water. This parameter change suppresses ozone decomposition reactions while maintaining the ultra-pure water's cleaning capabilities, thereby extending the ozone half-life period without compromising cleaning quality.

Inventive Principle:

Principle #35Parameter changes

2Power

If ozone concentration is increased to enhance cleaning capability, then cleaning performance is improved, but ozone decomposition is accelerated

Engineering Contradiction:

Improvecleaning capabilityVSAvoidozone stability

Core Design Contradiction:

PowerVSDuration of action of stationary object

Solution Approach 1:

The invention modifies the chemical environment parameter by introducing trace organic solvent to suppress ozone decomposition kinetics. This allows the system to maintain high ozone concentration and strong cleaning capability while preventing accelerated decomposition, thus resolving the contradiction between cleaning power and ozone stability.

Inventive Principle:

Principle #35Parameter changes

3Duration of action of stationary object

If organic solvent is added to extend ozone half-life, then ozone stability is improved, but organic carbon residue may form on substrate

Engineering Contradiction:

Improveozone half-life periodVSAvoidorganic carbon residue

Core Design Contradiction:

Duration of action of stationary objectVSObject-generated harmful factors

Solution Approach 1:

The invention precisely controls the concentration parameter of organic solvent addition to an extremely low range (0.01-10 ppm). At this trace level, the organic solvent sufficiently suppresses ozone decomposition to extend half-life while remaining below the threshold that would cause organic carbon residue formation on the semiconductor substrate.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The invention creates a local chemical environment modification by adding trace organic solvent that specifically targets ozone decomposition pathways without affecting the overall ultra-pure water properties or leaving harmful residues on the substrate surface.

Inventive Principle:

Principle #3Local quality

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 addition of a trace amount of organic solvent effectively extends the ozone half-life period in ultra-pure ozone water, maintaining high ozone concentration and preventing organic carbon residue, thereby enhancing cleaning capability and efficiency on semiconductor substrates without deteriorating their characteristics.

Implementation Method 1

Adding a trace amount of an organic solvent, such as ethanol or isopropyl alcohol, to the ultra-pure ozone water using a porous polymer membrane

Methodology Applied

Scientific EffectPermeation: Permeation

Implementation Method 2

the water has been added with an organic solvent containing an amount of organic carbon capable of suppressing a reduction of the half-life period of ozone

Methodology Applied

Scientific EffectChemical inhibition:

Implementation Method 3

the ozone water can induce a strong oxidative reaction and also advantageously a resultant product from decomposition thereof is oxygen that may help simplify a waste water treatment after the cleaning of the semiconductor substrates

Methodology Applied

Scientific EffectOxidation: Oxidation

Implementation Method 4

an ultraviolet ray is irradiated to the ultra-pure water to decompose and thus remove the amount of organic carbon contained in the ultra-pure water

Methodology Applied

Scientific EffectPhotodissociation: Photodissociation

Data Source

PatentUS7678200B2Technique on ozone water for use in cleaning semiconductor substrate

Publication Date: 2010.03.16 DE NORA PERMELEC LTD

AI summary

An ultra-pure ozone water comprising an increased amount of an organic carbon capable of suppressing the reduction of the half-life period of ozone; and a method for producing the ultra-pure ozone water which comprises adding an organic solvent containing the above organic carbon to an ultra-pure ozone water containing a trace amount of the organic carbon. The above ultra-pure ozone water exhibits an increased half-life period of ozone, and thus, when used in cleaning a semiconductor substrate, allows the cleaning with an ozone water having an enhanced content of ozone, which results in exhibiting an enhanced cleaning capability and cleaning efficiency for an organic impurities, metallic impurities and the like adhered to the substrate, due to enhanced oxidizing action of ozone.