Bevel Mask Inclined Surface for Substrate Back Side Plasma Uniformity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing substrate processing methods face challenges in achieving uniform processing on the back side of a substrate while suppressing processing on the front side, leading to issues like non-uniform film formation, pattern misalignment, and incomplete chucking due to the use of bevel masks that conceal the outer edge of the substrate's back side.
Innovation Solution
A substrate processing apparatus and method utilizing a bevel mask with an inclined surface that increases in vertical distance towards the center, allowing for uniform plasma treatment on the back side of the substrate without affecting the front side, using a susceptor and upper cover configuration to prevent plasma exposure on the bevel area.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If the bevel mask is made close to the bevel of the substrate to suppress processing on the front side, then the front side processing is suppressed, but the outer edge of the back side of the substrate is concealed, making uniform processing on the back side impossible
Solution Approach 1:
The bevel mask is designed with a stepped structure that utilizes vertical dimensionality to create different exposure zones. The first bevel surface is positioned at a first distance from the front side, while the second bevel surface is positioned at a second distance, creating a stepped configuration that allows the front side to be shielded while the back side remains exposed for uniform processing.
Solution Approach 2:
The bevel mask is divided into multiple surfaces (first bevel surface and second bevel surface) at different distances from the front side of the substrate. This segmentation allows different regions of the mask to perform different functions: the first bevel surface shields the front side while the second bevel surface allows plasma exposure for back side processing.
2Object-affected harmful factors
If the bevel mask conceals the outer edge of the back side of the substrate, then front side processing is suppressed, but it causes pattern misalignment and defective film formation
Solution Approach 1:
By introducing vertical distance variation through the stepped bevel structure, the patent enables the front side to be protected while the back side remains accessible for processing. The second bevel surface is positioned at a greater distance from the front side, ensuring plasma can reach the back side edges for accurate pattern formation without compromising front side suppression.
3Object-affected harmful factors
If the bevel mask is positioned to suppress front side film formation, then front side protection is achieved, but film thickness in the bevel region becomes smaller than in the center
Solution Approach 1:
The bevel mask is segmented into multiple surfaces at different vertical positions. The first bevel surface at a first distance and the second bevel surface at a second distance create zones of different plasma exposure, allowing the front side to be suppressed while the back side receives uniform plasma treatment for consistent film thickness.
Solution Approach 2:
The stepped configuration utilizes the vertical dimension to differentiate between front side protection and back side processing zones. This dimensional approach allows simultaneous achievement of front side suppression and back side film thickness uniformity through controlled plasma exposure at different heights.
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
Enables uniform processing on the back side of the substrate, preventing warpage and ensuring complete chucking and accurate pattern formation by isolating the plasma treatment to the back side while avoiding interference with the front side.
Implementation Method 1
uniform plasma treatment on the back side of the substrate
Data Source
AI summary
Examples of a substrate processing apparatus include a chamber, a shielding component that is a susceptor or an upper cover provided in the chamber, and a bevel mask that is provided in the chamber and has an inclined surface on which a vertical distance from the shielding component increases toward a center side of the shielding component.