Semiconductor Wafer Storage in Hydrogen-Pressurized Hermetic Enclosures
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for transporting and storing semiconductor wafers in hermetic enclosures face challenges with maintaining a pure neutral gas environment, leading to oxidation and contamination due to pressure changes and degassing issues, which require costly and complex ultra-high vacuum technologies.
Innovation Solution
A method involving a hermetic enclosure filled with hydrogen at a pressure between 10^-1 and 4*10^3 Pa, optionally with inert gases like argon, nitrogen, or helium, to create a controlled atmosphere that limits oxidation and contamination while being easier and less expensive to implement than ultra-high vacuum systems.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a hermetic enclosure is filled with neutral gas at ambient pressure to prevent oxidation, then the wafer is protected from oxidation, but the gas purity cannot be 100% guaranteed and pressure changes cause adsorption/desorption contamination
Solution Approach 1:
The patent applies inert atmosphere principle by filling the hermetic enclosure with hydrogen gas (an inert/protective atmosphere) at reduced pressure. This creates a protective environment that prevents oxidation of the wafer surface while the reduced pressure minimizes gas-related contamination issues. The hydrogen atmosphere serves both to protect from oxidation and to reduce adsorption/desorption effects compared to ambient pressure neutral gases.
Solution Approach 2:
The patent changes the pressure parameter from ambient pressure to reduced pressure (vacuum range). This parameter change addresses the gas purity reliability issue by reducing the total number of gas molecules present, thereby minimizing potential contamination from adsorption/desorption processes while maintaining the protective atmosphere function.
2Object-affected harmful factors
If vacuum is established inside the container to avoid gas purity issues, then oxidation is prevented, but outgassing from polymer walls and seals releases carbon compounds and requires expensive ultra-high vacuum technologies
Solution Approach 1:
The patent introduces hydrogen gas into the enclosure to create an inert/protective atmosphere. This active protective gas environment prevents oxidation more effectively than simple vacuum, while the specific choice of hydrogen at controlled pressure helps manage outgassing issues by providing a chemically active atmosphere that can handle carbon compounds from polymer outgassing.
Solution Approach 2:
The patent optimizes the pressure parameter within a specific range (10^-1 to 4×10^3 Pa) rather than using extreme ultra-high vacuum. This moderate vacuum level reduces outgassing compared to atmospheric pressure while avoiding the extreme conditions that would require expensive metal seals and ultra-high vacuum equipment. The controlled pressure range balances protection needs with material compatibility.
3Manufacturing precision
If ultra-high vacuum is maintained to prevent contamination, then wafer surface quality is preserved, but expensive metal boxes and seals are required and pumping must be maintained continuously
Solution Approach 1:
The patent changes the pressure parameter from ultra-high vacuum (10^-9 mbar) to a moderate vacuum range (10^-1 to 4×10^3 Pa). This parameter relaxation maintains adequate wafer surface quality protection while dramatically reducing equipment complexity, allowing the use of polymer seals and simpler pumping systems rather than expensive ultra-high vacuum infrastructure.
Solution Approach 2:
The patent introduces a protective hydrogen atmosphere to compensate for the reduced vacuum level. This inert environment actively protects the wafer surface quality that would otherwise be compromised by the higher pressure, allowing the system to achieve good surface quality with less complex equipment.
4Object-affected harmful factors
If hydrogen is used to create a controlled atmosphere, then oxidation and carbonaceous contamination are reduced, but the system requires pressure control between 10^-1 and 4×10^3 Pa
Solution Approach 1:
The patent uses hydrogen gas to create a protective inert atmosphere that actively reduces surface contamination. Hydrogen's chemical properties provide superior protection against oxidation and carbonaceous contamination compared to neutral gases, justifying the pressure control requirements.
Solution Approach 2:
The patent optimizes the pressure parameter within a specific range that balances contamination protection with practical equipment requirements. This pressure range (10^-1 to 4×10^3 Pa) is higher than ultra-high vacuum, allowing simpler equipment, but low enough to maintain effective contamination protection when combined with the hydrogen atmosphere.
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 effectively reduces surface contamination of semiconductor wafers by maintaining a stable, non-reactive environment that minimizes oxidation and carbonaceous contamination, making it suitable for transporting and storing wafers with reduced pressure constraints and cost-effective equipment.
Implementation Method 1
This approach effectively reduces surface contamination of semiconductor wafers by maintaining a stable, non-reactive environment that minimizes oxidation and carbonaceous contamination
Data Source
Figure 1~2
AI summary
The invention relates to a method for the transportation and/or storage of at least one semiconductor plate, in which the plate is disposed in a hermetic container (1) filled with hydrogen at a pressure of between 10-1 and 4*103 Pa and, optionally, at least one inert gas, the total pressure in the casing being between 10-1 and 5*104 Pa.