Substrate Holder Segmented Projection for Uniform Adhesion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional substrate holders with monotonic convex placement surfaces often result in nonuniform adhesion between the substrate and the surface, leading to potential gaps and uneven temperature distribution during substrate heating.
Innovation Solution
A substrate holder design featuring a ceramic base member with an annular projected part on the outer periphery and multiple projected parts on the inner side, where the upper surface includes a circular area with a flat and curved envelope surface, ensuring stable substrate attraction and preventing inclination, thus minimizing gaps and heat spots.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a monotonic convex placement surface is used, then the substrate can be attracted to the surface by suction, but the substrate may become inclined and create local gaps, leading to nonuniform adhesion
Solution Approach 1:
The placement surface is segmented into multiple projected parts (first, second, and third projected parts) with different heights and configurations. This segmentation allows different regions to perform different functions: the first projected part provides initial contact, the second projected part maintains uniform adhesion, and the third projected part prevents inclination, collectively solving the nonuniform adhesion problem.
Solution Approach 2:
Different regions of the placement surface are given different local qualities through the projected parts. The first projected part has a specific height range (0.01-0.05mm) for initial substrate contact, the second projected part has a different height range (0.05-0.1mm) for maintaining adhesion, and the third projected part extends further (0.1-0.5mm) to prevent inclination. This local differentiation ensures uniform adhesion across the substrate surface.
2Reliability
If the substrate is attracted to the placement surface by suction, then the substrate can be held securely, but gaps may form between the substrate and placement surface, particularly at the outer peripheral part
Solution Approach 1:
The first projected part is designed to make contact with the substrate before the second projected part during the suction process. This preliminary action ensures that the substrate is properly positioned and inclined is prevented before full suction is applied, thereby preventing gap formation at the outer peripheral part.
Solution Approach 2:
The third projected part is specifically designed to prevent substrate inclination by extending further than other parts. This preliminary anti-action counteracts the tendency of the substrate to incline during suction, ensuring uniform contact between the substrate and placement surface throughout the holding process.
3Device complexity
If a simple flat placement surface is used, then the structure is simple, but the substrate may not be statically determined quickly, leading to prolonged inclination and nonuniform temperature distribution
Solution Approach 1:
The placement surface is segmented into multiple projected parts with different heights and configurations, which work together to quickly statically determine the substrate. The first projected part provides initial contact points, the second projected part ensures uniform adhesion, and the third projected part prevents inclination, collectively achieving rapid substrate stabilization without excessive complexity.
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 design enhances the uniformity of substrate adhesion and temperature distribution by statically determining the entire substrate surface quickly, preventing local gaps and heat spots, and ensuring consistent heating performance.
Implementation Method 1
The substrate is held on the placement surface by attracting the substrate to the placement surface by suction
Data Source
AI summary
There is provided a substrate holder including: a ceramic base member, an electrode and a shaft. The ceramic base member is provided with: an annular projected part and a plurality of projected parts. A circular area of which diameter is not less than 0.4 times an inner diameter of the cylindrical part is provided on a center in an upper surface of the ceramic base member. A first envelope surface of projected parts arranged in the circular area is a flat surface, and a second envelope surface of projected parts arranged at outside of the circular area is a curved surface. Alternatively, the first envelope surface is a curved surface having a first curvature and the second envelope surface is a flat surface or a curved surface having a second curvature which is different from the first curvature.