Housing Buffer Space for Substrate Processing Oxygen Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing substrate processing apparatuses face challenges in maintaining a reduced oxygen concentration within the loading region to prevent oxidation of titanium nitride (TiN) films, leading to increased manufacturing costs due to the need for high inert gas supply and sealability, which is difficult to achieve without allowing outside air to diffuse into the internal space.
Innovation Solution
A housing design with a box structure that includes a buffer space and an inert gas pipe system, where the inert gas is supplied to maintain positive pressure and leaks through carefully controlled gaps to reduce oxygen concentration, using a cover member to manage gas flow and minimize oxygen diffusion from the outside.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a mass of inert gas is supplied to the box structure to reduce oxygen concentration in the loading region, then the oxidation of Ti film surface is prevented, but manufacturing costs increase
Solution Approach 1:
The internal space is divided into two regions: a first region (internal space of box structure) and a second region (buffer space). The cover member with selective permeability separates these regions, allowing inert gas to flow from the first region to the second region while preventing outside air from entering the first region. This segmentation enables reduced inert gas supply while maintaining low oxygen concentration in the loading region.
Solution Approach 2:
The buffer space acts as an intermediary region between the internal space and the external atmosphere. Inert gas flows through the cover member into the buffer space, and the pressure differential drives the gas flow in a way that prevents outside air diffusion into the internal space. This intermediary structure reduces the amount of inert gas needed while maintaining protection against oxidation.
2Quantity of substance
If the sealability of the box structure is increased to reduce inert gas supply amount, then manufacturing costs are reduced, but outside air diffusion into the internal space becomes more difficult to prevent
Solution Approach 1:
The cover member is positioned specifically at the opening section of the box structure, providing selective permeability only where needed. This local application of the permeability feature allows the rest of the box structure to maintain its sealing, while the cover member controls gas flow at the critical interface with the external atmosphere.
Solution Approach 2:
The system maintains an inert atmosphere in the internal space by utilizing the pressure differential created by inert gas supply. The cover member's selective permeability ensures that the inert gas flows in a direction that prevents outside air from entering, maintaining the inert environment without requiring complete sealing.
3Reliability
If the internal space is kept in positive pressure by inert gas, then outside air introduction is prevented, but inert gas leakage to the outside causes reverse diffusion of outside air into the internal space
Solution Approach 1:
The harmful effect of reverse diffusion is extracted and redirected to the buffer space. The cover member with selective permeability allows inert gas to flow into the buffer space, and the buffer space acts as a sink that captures any outside air that might otherwise diffuse back into the internal space. This separates the harmful diffusion path from the internal space.
Solution Approach 2:
The inert gas leakage, which would normally cause reverse diffusion of outside air, is converted into a beneficial flow pattern. The leaked inert gas enters the buffer space and creates a pressure differential that actually prevents outside air from entering the internal space. The potential harm of leakage is transformed into a mechanism that reinforces the inert atmosphere protection.
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 design effectively reduces oxygen concentration in the internal space to prevent oxidation of TiN films, thereby reducing manufacturing costs and maintaining the required low oxygen levels without extensive reconstruction of existing apparatuses.
Implementation Method 1
the internal space is kept in a positive pressure by the inert gas supplied thereto through the inert gas pipe
Implementation Method 2
Gas in the internal space is leaked through the first gap to the buffer space and the gas in the buffer space is leaked to the outside through the second gap
Data Source
AI summary
According to an embodiment of the present disclosure, a substrate processing apparatus including a housing is provided. The housing having an internal atmosphere of a reduced oxygen concentration includes a box structure configured to accommodate a substrate holder which receives a plurality of substrates therein and including a first gap and a second gap. Further, the housing includes an inert gas pipe connected to the box structure, and configured to supply an inert gas to the box structure, a cover member mounted in the box structure, and a buffer space formed between an internal space of the box structure and the cover member.