Adjustable Gas Distribution Plate for CVD Flow Uniformity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional chemical vapor deposition (CVD) systems lack adequate control over gas flow distribution across the substrate surface, leading to non-uniform film thickness and epitaxially-grown films, especially when increasing process gas flow rates to enhance throughput.
Innovation Solution
A gas manifold system with a baffle plate and inject insert liner assembly, featuring adjustable plugs and tapered gas flow channels, allows for precise control of gas flow distribution by varying the size and shape of holes in the baffle plate and the design of inject insert liners to prevent recirculation cells and crosstalk between flow zones.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional baffle plates with fixed hole sizes are used, then the device structure is simple, but the gas flow distribution uniformity across the substrate surface is inadequate
Solution Approach 1:
The baffle plate is designed with adjustable plugs that can be inserted into different holes to dynamically change the gas flow distribution pattern. This allows the system to adapt to different process requirements without changing the basic manifold structure, resolving the contradiction between maintaining uniformity and avoiding complexity.
Solution Approach 2:
Different regions of the baffle plate can have different hole sizes and configurations, with selective plugs placed in specific holes to optimize gas flow distribution for different areas of the substrate. This local customization achieves uniform flow distribution without requiring complete structural redesign.
2Adaptability or versatility
If multiple flow zones with different gases are used in conventional manifolds, then the process versatility is improved, but crosstalk between zones causes unpredictable tuning results
Solution Approach 1:
The manifold is divided into separate, isolated flow zones with dedicated channels for each zone. This segmentation prevents crosstalk between different gas flows while maintaining the ability to independently control each zone, thus preserving versatility without sacrificing control precision.
3Manufacturing precision
If recirculation cells form in conventional inject inserts, then the device structure is simple, but the gas flow distribution uniformity is degraded
Solution Approach 1:
The inject insert design incorporates features that prevent recirculation cell formation before they can degrade flow uniformity. By designing channels with appropriate geometry and flow direction control, the system proactively eliminates the harmful recirculation effect without requiring complex additional components.
4Productivity
If higher process gas flow rates are used, then the productivity is increased, but the film thickness uniformity across the substrate deteriorates
Solution Approach 1:
The adjustable plug system allows the gas flow distribution pattern to be dynamically optimized for different flow rates. When operating at higher flow rates for increased productivity, the plug configuration can be adjusted to maintain uniform distribution, preventing film thickness non-uniformity even at elevated throughput conditions.
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 configuration achieves uniform gas flow distribution across the substrate surface, maintaining layer thickness uniformity even at higher gas flow rates, enabling improved film deposition quality and increased throughput in CVD processes.
Implementation Method 1
The gas distribution plate is disposed between the gas injecting port and the processing chamber, and includes an elongate planar body and an array of holes therein. The plug is sized to be received within one of the holes, and includes an orifice therethrough for permitting the passage of gas.
Implementation Method 2
the inject insert liner assembly defines gas flow channels therein extending along a lengthwise direction of the system, wherein each channel includes an inlet and an outlet, and at least one channel is tapered along the lengthwise direction of the system in at least one of a vertical or horizontal direction
Data Source
AI summary
In one aspect, a system for depositing a layer on a substrate is provided. The system includes a processing chamber, a gas injecting port, a gas distribution plate, and a plug. The gas injecting port is disposed upstream from the processing chamber. The gas distribution plate is disposed between the gas injecting port and the processing chamber, and includes an elongate planar body and an array of holes therein. The plug is sized to be received within one of the holes, and includes an orifice therethrough for permitting the passage of gas. The plug is capable of being removably secured to the gas distribution plate within one of the holes.