Gas Introduction Structure for Uniform Wafer Processing

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

In thermal processing apparatuses, there is a challenge in uniformly supplying processing gases to wafers, leading to variations in gas concentration and potential film deposition issues within the gas supply pipes, which affects the efficiency and uniformity of film formation on wafers.

Innovation Solution

A gas introduction structure where a dilution gas is supplied to the upper portion of the processing gas supply pipe, reducing gas concentration variations and suppressing film deposition by connecting the dilution gas supply pipe with the processing gas supply pipe, ensuring uniform gas distribution through the gas discharge holes.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If processing gas is supplied through a gas supply pipe with gas discharge holes, then wafers can be processed in a thermal processing apparatus, but gas concentration variations occur and film deposition happens inside the gas supply pipe

Engineering Contradiction:

Improvewafer processing efficiencyVSAvoidgas concentration uniformity

Core Design Contradiction:

ProductivityVSManufacturing precision

Solution Approach 1:

The patent applies local quality by introducing dilution gas at specific locations (upper portion of the gas supply pipe) to create non-uniform gas composition that results in uniform processing conditions. The dilution gas concentration varies along the pipe length, with higher concentration near the top, which compensates for the accumulation of processing gas and maintains consistent gas composition at each wafer position.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent changes the composition parameter of the gas mixture by introducing dilution gas. This alters the physical-chemical properties of the gas phase, specifically the concentration of reactive species, to prevent film deposition and maintain uniform processing conditions throughout the vertical processing chamber.

Inventive Principle:

Principle #35Parameter changes

2Productivity

If processing gas flows through the gas supply pipe, then wafers can be processed, but film deposits form on the inner wall of the gas supply pipe

Engineering Contradiction:

Improveprocessing throughputVSAvoidfilm deposition in gas supply pipe

Core Design Contradiction:

ProductivityVSObject-generated harmful factors

Solution Approach 1:

The patent converts the harmful accumulation of processing gas (which causes film deposition) into a beneficial effect by introducing dilution gas. The dilution gas reacts with or dilutes the accumulated processing gas, transforming the harmful high-concentration zone into a controlled environment that prevents film deposition while maintaining processing efficiency.

Inventive Principle:

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

Solution Approach 2:

The dilution gas creates an inert or less reactive atmosphere in the upper portion of the gas supply pipe, preventing the chemical reactions that lead to film deposition. This inert environment protects the inner wall of the gas supply pipe from harmful film formation while allowing continuous processing.

Inventive Principle:

Principle #39Inert atmosphere (Inert environment)

3Productivity

If the gas supply pipe extends vertically to accommodate multiple wafers, then batch processing is enabled, but gas concentration varies along the vertical direction

Engineering Contradiction:

Improvebatch processing capabilityVSAvoidgas concentration consistency

Core Design Contradiction:

ProductivityVSStability of the object's composition

Solution Approach 1:

The patent applies preliminary action by introducing dilution gas into the upper portion of the gas supply pipe before the processing gas can accumulate and cause concentration variations. This preemptive introduction of dilution gas ensures that the gas composition remains consistent throughout the vertical extent of the processing chamber, enabling uniform batch processing of multiple wafers.

Inventive Principle:

Principle #10Preliminary action

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 ensures uniform gas supply to wafers, reducing film deposition and concentration variations within the gas supply pipes, thereby enhancing the efficiency and consistency of film formation processes.

Implementation Method 1

a dilution gas is supplied to a portion of the processing gas supply pipe

Methodology Applied

Scientific EffectDiffusion: Diffusion

Implementation Method 2

processing gas is introduced from one end toward the other end of the processing gas supply pipe

Methodology Applied

Scientific EffectConvection: Convection

Data Source

PatentUS11725281B2Gas introduction structure, thermal processing apparatus and gas supply method

Publication Date: 2023.08.15 TOKYO ELECTRON LTD

AI summary

A gas introduction structure for supplying a processing gas into a vertically-elongated processing container, includes a processing gas supply pipe extending along a longitudinal direction of the processing container in the processing container and having a plurality of gas discharge holes formed along the longitudinal direction, the processing gas supply pipe configured so that the processing gas is introduced from one end toward the other end thereof, wherein a dilution gas is supplied to a portion of the processing gas supply pipe that is closer to the other end than the one end of the processing gas supply pipe.