Shower Plate Protrusions for Plasma CVD Film Uniformity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional plasma CVD apparatuses face challenges in forming thin films with desired properties stably and with excellent controllability, as they have narrow operable ranges and can transfer shower plate patterns to film thickness distributions, leading to non-uniform films.
Innovation Solution
A shower plate design with multiple apertures and protrusions that increase the surface area by at least 40% and form a sheath with a surface area nearly equal to or greater than the physical surface area, allowing for improved plasma distribution and film formation controllability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a conventional shower plate with gas inlet holes is used, then gas can be introduced into the vacuum chamber, but the shower plate pattern is transferred to the film thickness distribution, causing non-uniform thin film formation
Solution Approach 1:
The shower plate incorporates protrusions at specific locations to create localized plasma generation zones. These protrusions are strategically positioned to enhance plasma density in regions where additional deposition is needed, thereby compensating for the non-uniformity caused by the aperture pattern and achieving more uniform film thickness across the substrate.
Solution Approach 2:
The invention adds a vertical dimension to the shower plate structure by incorporating protrusions that extend toward the substrate. This three-dimensional structure creates varying plasma density zones at different heights, allowing for more precise control over film thickness distribution in the vertical direction while maintaining horizontal uniformity.
2Manufacturing precision
If the operable range is narrowed to achieve desired film properties, then film quality can be improved, but controllability and stability are reduced
Solution Approach 1:
The shower plate design enables dynamic control of plasma distribution through the protrusion structure. By adjusting gas flow rates and RF power levels, the system can adaptively optimize film properties across a broader operable range, maintaining both film quality and process flexibility simultaneously.
Solution Approach 2:
The invention allows for independent optimization of multiple process parameters (gas flow, RF power, pressure) while the protrusion structure provides inherent spatial control. This multi-parameter control capability expands the operable range while maintaining precise control over film properties such as stress, composition, and thickness uniformity.
3Manufacturing precision
If protrusions are added to increase surface area by at least 40%, then plasma distribution and film formation controllability are improved, but device complexity increases
Solution Approach 1:
The shower plate is segmented into multiple protrusion elements distributed across its surface. Each protrusion acts as an independent plasma generation zone, allowing for modular control of plasma distribution. This segmentation approach achieves improved film formation controllability while keeping individual protrusion structures simple and manufacturable.
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 enables the stable formation of thin films with desired properties, such as controlled internal stress and reduced hydrogen concentration, while preventing abnormal discharge and ensuring uniform film thickness.
Implementation Method 1
a surface area of the base surface and the protrusions is greater by at least 40% than a calculated surface area of the base surface if no protrusions are provided
Implementation Method 2
a surface area when extending from the base surface and the protrusions by a sheath generated by plasma exposure is nearly or substantially equal to or greater than the surface area of the base surface and the protrusions
Implementation Method 3
generating a plasma between the susceptor and the shower plate by applying radio-frequency energy therebetween
Implementation Method 4
depositing a film on the substrate
Data Source
AI summary
A shower plate 122 has protrusions 22 formed on the front face used with a first electrode in a plasma CVD apparatus. A plane-surface portion 23 is left around apertures of gas inlet holes 21 formed in the shower plate 122. With protrusions 22 being formed, a surface area of the first electrode is increased.