FOUP Sealing and Gas Purge for Ultra-Low Oxygen Storage

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Semiconductor fabrication facilities face challenges in maintaining optimal oxygen and water content within front opening unified pods (FOUPs) to prevent wafer contamination and oxidation during processing, transportation, and storage, as existing systems fail to effectively control these environments.

Innovation Solution

The implementation of a system that includes a FOUP with a low outgassing storage chamber, a sealing mechanism using a pressure applicator and seal band, and a pipeline system with a diffuser and controller to adjust oxygen and water content, maintaining concentrations below 1 ppm through vacuum or nitrogen purges, ensuring an airtight seal and minimizing contamination.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If existing storage systems are used for FOUPs, then wafer carriers can be stored and transported, but oxygen and water content cannot be effectively controlled, leading to wafer contamination and oxidation

Engineering Contradiction:

Improvewafer protection from contaminationVSAvoidoxygen and water content

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent applies inert atmosphere by introducing nitrogen gas into the FOUP storage chamber to displace oxygen and moisture. The system includes nitrogen supply lines and vacuum pumps that create a controlled inert environment, maintaining oxygen and water content below 1 ppm levels, thereby preventing wafer oxidation and contamination during storage and transport.

Inventive Principle:

Principle #39Inert atmosphere (Inert environment)

2Reliability

If a sealing mechanism is implemented to control gas content, then wafer protection is improved, but system complexity increases

Engineering Contradiction:

Improveenvironmental controlVSAvoidsealing and purge system

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent segments the FOUP into distinct functional zones: a storage chamber for wafers, a sealing mechanism with movable seals, and integrated purge systems. The sealing mechanism includes movable seals that divide the chamber into separate regions, allowing independent control of gas content in different zones while maintaining overall system manageability.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The sealing mechanism serves multiple functions: it seals the storage chamber to maintain inert atmosphere, divides the chamber into separate zones for differential pressure control, and works integrated with vacuum and nitrogen purge systems. This multi-functionality reduces the need for separate dedicated components for each function.

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Reliability

If vacuum and nitrogen purge systems are used to maintain low oxygen levels, then wafer integrity is preserved, but energy consumption increases

Engineering Contradiction:

Improvewafer oxidation preventionVSAvoidpurge system energy

Core Design Contradiction:

ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent implements periodic action through controlled cycles of vacuum pumping and nitrogen purging. Rather than continuous operation, the system alternates between vacuum phases to remove gases and nitrogen injection phases to replenish the inert atmosphere. This periodic operation significantly reduces energy consumption compared to continuous purge systems while maintaining oxygen and water content below 1 ppm.

Inventive Principle:

Principle #19Periodic 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 solution effectively maintains low oxygen and water levels within the FOUPs, preventing wafer oxidation and contamination, thereby ensuring the integrity of wafers during storage, transportation, and processing by creating a controlled environment with precise gas management.

Implementation Method 1

a pressure applicator and seal band to engage the sidewall surface and form an airtight seal

Methodology Applied

Scientific EffectPressure: Pressure Increase

Implementation Method 2

maintaining concentrations below 1 ppm through vacuum or nitrogen purges

Methodology Applied

Scientific EffectVacuum: Vacuum

Implementation Method 3

maintaining concentrations below 1 ppm through vacuum or nitrogen purges

Methodology Applied

Scientific EffectGas flow: Convection

Implementation Method 4

a pipeline system with a diffuser and controller to adjust oxygen and water content

Methodology Applied

Scientific EffectDiffusion: Diffusion

Data Source

PatentUS9455169B2Ultra-low oxygen and humility loadport and stocker system

Publication Date: 2016.09.27 TAIWAN SEMICONDUCTOR MANUFACTURING CO LTD

AI summary

One or more pods for adjusting at least one of an oxygen content or a water content therein and methods of their use are provided, where one or more semiconductor wafer are selectively stored within a storage chamber of the pod. The pod comprises a storage chamber having a side wall surface defining an opening at one side thereof and a pod door fitted to the storage chamber at the opening so as to provide ingress and egress to the storage chamber. The pod door comprises a door body, a first door locking mechanism on the door body and a seal band configured to engage the sidewall surface. The first door locking mechanism comprises a first pressure applicator, a first key assembly and a first connector-rod.