Rotary Plate Annular Elevation Prevents Substrate Coating Defects
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing rotary plates for coating substrates/wafers often result in coating on undesirable surfaces, particularly the lower side, due to capillary forces between the substrate and the plate, leading to reduced coating quality.
Innovation Solution
A rotary plate design featuring suction points on one side of the substrate and an annular elevation matching the substrate's diameter, with a movable and fixed part configuration, prevents coating on the lower side by securely holding the substrate via suction points and minimizing contact with the annular elevation, thereby enhancing coating quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the substrate is held directly on the rotary plate surface, then the substrate can be easily positioned and coated, but capillary forces cause coating to pass onto the lower side of the substrate
Solution Approach 1:
The rotary plate is segmented into a flat base plate and a separate annular elevation structure. The substrate is positioned on the annular elevation rather than directly on the base plate, creating spatial separation between the substrate and the harmful capillary action zone. This segmentation allows the coating to be applied only to the intended surfaces while preventing it from passing to the lower side.
Solution Approach 2:
The annular elevation acts as an intermediary structure between the rotary plate and the substrate. It provides a controlled interface that allows secure positioning of the substrate through suction points while preventing direct contact between the substrate's lower side and the rotary plate surface, thereby eliminating the capillary force pathway that would cause unwanted coating deposition.
2Reliability
If suction points are used to hold the substrate, then the substrate is securely fixed during rotation, but the substrate may still be damaged by improper holding elements
Solution Approach 1:
The invention uses suction points (pneumatic holding) instead of mechanical clamps or other physical holding elements. The suction points create a vacuum field that securely holds the substrate during rotation without requiring direct mechanical contact that could cause damage. This pneumatic holding method provides uniform, damage-free fixation across the substrate surface.
3Device complexity
If the rotary plate has a simple flat surface, then the device complexity is low, but the substrate cannot be securely held and coating quality deteriorates
Solution Approach 1:
The rotary plate is divided into functional segments: a flat base plate for structural support and an annular elevation structure for substrate positioning. This segmentation adds only the necessary complexity to achieve secure substrate holding and prevent coating defects, without over-complicating the overall device design.
Solution Approach 2:
The annular elevation provides localized structural enhancement only where needed for substrate positioning, rather than complicating the entire rotary plate structure. The suction points are strategically positioned within the annular elevation to provide focused holding capability. This local quality approach maintains simplicity in non-critical areas while adding complexity only where it directly improves coating quality.
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
The solution effectively prevents coating on undesirable surfaces, ensuring higher quality coatings by securely holding the substrate and reducing capillary forces, while allowing for easy substrate placement and removal.
Implementation Method 1
A rotary plate (1) for holding a substrate/wafer for a coating device has a plurality of suction points (5.1-5.4) on a side assigned to the substrate
Implementation Method 2
This takes place, for example, due to capillary forces which arise between the substrate/wafer and the rotary plate on which the substrate/wafer rests during the coating
Data Source
AI summary
A rotary plate for holding a substrate for a coating device, which rotary plate comprises a plurality of suction points, is intended to be characterized by an annular elevation, wherein a diameter of the annular elevation substantially corresponds to a diameter of the substrate.