Evaporation Deposition Pressure Stabilizing Chamber
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional vapor deposition methods face challenges in maintaining a constant evaporation rate and achieving uniformity of thin films, particularly when multiple materials are used, leading to non-uniformity and interference issues in large-scale film deposition processes.
Innovation Solution
The method involves placing evaporation materials in vessels with heaters, controlling evaporation using a cover to achieve a first vapor saturation pressure, and directing the vapor to a pressure stabilizing chamber before entering a vacuum environment, maintaining a constant pressure difference to ensure a consistent deposition rate and uniform film formation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If conventional vapor deposition is used with multiple independent evaporation sources, then large area thin films can be produced, but the uniformity of the thin film deteriorates due to different evaporation angles and interference between sources
Solution Approach 1:
The system divides the evaporation process into two independent stages: first, multiple evaporation sources deposit materials simultaneously in separate evaporation vessels; second, the deposited layers are transferred to a rotation stage for uniformization. This segmentation allows each source to operate independently without interference while achieving uniform final distribution through mechanical rotation.
Solution Approach 2:
The invention introduces a temporal dimension to the deposition process by separating the simultaneous multi-source deposition from the uniformization step. Materials are deposited at different times from different sources, then the substrate rotates to redistribute the layers, transforming a spatial uniformity problem into a temporal process solution.
2Productivity
If evaporation material level decreases during deposition, then deposition continues, but temperature difference between center and edge increases causing evaporation rate change
Solution Approach 1:
The system pre-heats the evaporation vessels to their target temperatures before actual deposition begins. This preliminary heating ensures that when materials are introduced, the temperature conditions are already optimized and stable, preventing temperature fluctuations during the deposition process that would cause evaporation rate variations.
Solution Approach 2:
The system continuously monitors the deposition process and adjusts parameters to maintain consistent evaporation rates. By implementing feedback control, the system can compensate for changes in material level and temperature, ensuring stable deposition conditions throughout the process.
3Productivity
If multiple independent evaporation sources are used for mixing materials, then mass production capability is achieved, but interference between sources reduces thin film uniformity
Solution Approach 1:
The system separates the material mixing function from the evaporation source arrangement. Instead of requiring multiple sources to mix materials through spatial arrangement, each source deposits its material independently, and the rotation stage performs the mixing function by redistributing the deposited layers uniformly across the substrate surface.
Solution Approach 2:
The rotation stage acts as an intermediary mechanism between the multiple evaporation sources and the final thin film structure. It receives materials deposited from various sources and redistributes them uniformly, mediating the transition from non-uniform multi-source deposition to uniform final film composition.
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 results in highly stable and uniform thin films with minimal variation in composition and thickness, preventing changes in evaporation rate over time and enhancing the overall quality of the deposited films.
Implementation Method 1
heating the evaporation material by at least one heater
Implementation Method 2
the evaporation material is evaporated and volatilized
Implementation Method 3
the interior of the evaporation vessel has a first vapor saturation pressure when the evaporation material is heated to an evaporation state
Implementation Method 4
the vapor of the evaporation material flows from the pressure stabilizing chamber to the vacuum environment system due to the pressure difference
Implementation Method 5
the vacuum environment system has a vacuum background pressure
Implementation Method 6
vapor deposition is applied in a vacuum system to place an evaporation material in an evaporation vessel
Data Source
AI summary
In a method for evaporation depositing uniform thin films, a film is deposited on a substrate of a vacuum environment while maintaining a constant deposition rate. A cover is installed on a wall of the evaporation vessel. When the evaporation material is heated to an evaporation state and the interior of the evaporation vessel reaches a first vapor saturation pressure, the vapor of the evaporation material flows towards a pressure stabilizing chamber. When the pressure stabilizing chamber reaches a second vapor saturation pressure which is smaller than the first vapor saturation pressure, the vacuum environment has a vacuum background pressure which is smaller than the second vapor saturation pressure, so that the evaporation material vapor flows from the pressure stabilizing chamber towards the vacuum environment at constant rate due to the pressure difference, so as to evaporate the substrate.