Positive Displacement Pumping Chamber for ALD Purge Optimization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current deposition and etching processes, such as Atomic Layer Deposition (ALD), are hindered by long purge times, which account for approximately 75% of the total cycle time, significantly reducing equipment productivity.
Innovation Solution
The use of a moveable wall within the process chamber to vary the volume, allowing for rapid extraction and introduction of gases through exhaust and inlet valves, thereby reducing purge times and increasing the efficiency of gas distribution across the substrate.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of time
If traditional pumping methods are used to purge the chamber, then the chamber can be purged of reactant gases, but the purge time becomes excessively long (accounting for 75% of total cycle time)
Solution Approach 1:
The patent applies the dynamics principle by introducing a moveable wall (piston) that dynamically changes the chamber volume during the purge cycle. The piston rapidly reduces the chamber volume to compress and expel reactant gases, then restores the volume for the next deposition cycle. This dynamic volume adjustment enables purge times to be reduced to match the short exposure times, transforming the previously static chamber into an actively controlled system that dramatically improves productivity.
2Productivity
If exposure times are reduced to increase film growth speed, then productivity improves, but adequate purging becomes more difficult to achieve
Solution Approach 1:
The moveable wall enables the chamber to dynamically adjust its volume in synchronization with the deposition cycle. During purge phases, the wall rapidly reduces volume to expel gases; during exposure phases, the wall restores volume to allow proper gas distribution. This dynamic adaptation allows exposure times to be reduced while maintaining adequate purging, as the purge time is now determined by the mechanical speed of the moveable wall rather than pump speed alone.
3Manufacturing precision
If the chamber volume is kept large to ensure adequate gas distribution, then uniform coating is achieved, but the purge time increases
Solution Approach 1:
The patent resolves this contradiction by making the chamber volume dynamic rather than static. The moveable wall maintains a large volume during exposure to ensure adequate gas distribution and uniform coating, then rapidly reduces the volume during purge to accelerate gas removal. This temporal separation of volume requirements allows both large-volume benefits (uniform coating) and small-volume benefits (fast purge) to be achieved at different stages of the cycle.
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 enables faster cycle times, increased productivity, and more efficient gas management, allowing for the rapid removal and distribution of gases, which can reduce the overall processing time by up to 75% compared to traditional methods.
Implementation Method 1
Positive displacement pumping chamber... a moveable wall displaceable to vary the process volume... moveable wall may be moveable to reduce the process volume to purge gas from the process volume through the exhaust outlet
Implementation Method 2
the moveable wall may be moveable to draw process gas through the inlet during the process part of the process cycle
Data Source
AI summary
A method is for processing a substrate. The method includes placing the substrate in a process volume and introducing a process gas or vapor into the process volume and/or subsequently removing gas or vapor from the volume. The step of introducing and/or removing the gas is at least partially performed by moving a movable wall to change the process volume in an appropriate sense.