Cross-Flow Purge for Optical Components in Semiconductor Chambers

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing axial flow gas purging systems in semiconductor fabrication chambers lead to cross-contamination of optical components due to the accumulation of contaminants in the purge gas, reduced pressure and flow at downstream components, and lack of deterministic control over purge processes.

Innovation Solution

A cross-flow purging system with inlet and exhaust ports aligned radially to the axial direction, allowing purge gas to flow orthogonally across optical components, minimizing contamination transfer and enabling customized pressure and flow control for individual components.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If axial flow purge gas is used to remove contaminants from optical components, then contaminant removal is achieved, but cross-contamination occurs between components

Engineering Contradiction:

Improvecontaminant removal effectivenessVSAvoidcross-contamination between components

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The chamber is divided into separate purge zones with individual inlet and exhaust ports for each optical component. Each component has its own dedicated purge path, preventing contaminant transfer between components while maintaining effective contaminant removal from each zone.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Instead of flowing purge gas axially through the chamber from one end to the other, the system uses radial flow where purge gas enters through side walls and flows outward toward the optical components, then exhausts through separate ports. This reverses the conventional axial flow pattern to eliminate cross-contamination.

Inventive Principle:

Principle #13The other way round (Inversion)

2Reliability

If axial flow purge gas is used throughout the chamber, then overall purging is achieved, but pressure and flow are reduced at downstream components

Engineering Contradiction:

Improveoverall chamber purgingVSAvoidpurge gas pressure at downstream components

Core Design Contradiction:

ReliabilityVSStress or pressure

Solution Approach 1:

Multiple independent inlet and exhaust ports are distributed around the chamber perimeter, creating parallel purge paths. This segmentation allows each zone to maintain its own pressure and flow rates without being constrained by axial flow limitations, ensuring adequate purge gas availability at all locations.

Inventive Principle:

Principle #1Segmentation

3Reliability

If axial flow purge gas is used, then chamber purging is achieved, but deterministic control for individual components is lost

Engineering Contradiction:

Improvechamber purging effectivenessVSAvoiddeterministic control for individual components

Core Design Contradiction:

ReliabilityVSEase of operation

Solution Approach 1:

The purge system is divided into independently controllable zones with separate inlet and exhaust ports for each optical component. This allows deterministic control of purge gas flow to and from each component individually, enabling precise control over purging parameters for specific components without affecting others.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Each optical component zone has customized inlet and exhaust port configurations tailored to its specific purging requirements. This local quality approach allows different purge flow rates, pressures, and patterns for different components based on their individual contamination characteristics and operational needs.

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

This approach reduces cross-contamination, maintains higher purge gas pressures and flow rates, ensures efficient contaminant removal, and allows for deterministic control of the purge process, minimizing residue formation and extending the operational life of optical components.

Implementation Method 1

The purge gas flows in flow path 1114 through the chamber picking up contaminants in the chamber and on the optical components

Methodology Applied

Scientific EffectAdvection: Advection

Implementation Method 2

Purge gas is introduced at one end of chamber 1104 to remove contaminants in the chamber

Methodology Applied

Scientific EffectDiffusion: Diffusion

Data Source

PatentUS9662688B2Apparatus and method for cross-flow purge for optical components in a chamber

Publication Date: 2017.05.30 KLA CORP

AI summary

An apparatus for cross-flow purging for optical components in a chamber, including: a housing with first and second axial ends, a side wall extending in an axial direction and connecting the first and second axial ends, and the chamber formed by the first and second axial ends and the side wall; an optical component disposed within the chamber and fixed with respect to the housing via at least one connecting point on the optical component; an inlet port aligned with the side wall, between the first and second axial ends in the axial direction, in a radial direction orthogonal to the axial direction and arranged to inject a purge gas into the chamber and across the optical component in a radial direction orthogonal to the axial direction; and an exhaust port aligned with the side wall in the radial direction and arranged to exhaust the purge gas from the chamber.