Wafer Edge Plasma Layout Using a Side Ground Electrode
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing plasma processing technologies struggle to effectively perform plasma processing on the end parts of substrates, such as semiconductor wafers, due to the formation of etching by-products like polymers, which lead to particle formation in subsequent processes.
Innovation Solution
A plasma processing apparatus is designed with a substrate supporting member that excludes the end part to be processed, a high-frequency power supply, a dielectric substrate support, an opposing dielectric member, a side ground electrode, and a gas supply system to generate plasma locally at the end part of the substrate.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional plasma processing is applied to the entire substrate, then plasma coverage is improved, but etching by-products and particles are generated at the end parts
Solution Approach 1:
The patent applies local quality by creating plasma only at the end parts of the substrate through a dedicated side ground electrode, while the central processing region uses a different electrode configuration. This localized plasma generation eliminates by-product formation in non-critical areas while maintaining processing quality where needed.
Solution Approach 2:
The substrate processing is segmented into two distinct regions: the central area processed by the main electrode and the end parts processed by the side ground electrode. This segmentation allows different plasma conditions to be applied to different regions, preventing harmful by-products at the ends while maintaining overall processing effectiveness.
2Reliability
If a side ground electrode is positioned close to the substrate end part, then plasma generation at the end part is improved, but electrical coupling may cause unwanted effects
Solution Approach 1:
A dielectric member is introduced as an intermediary between the side ground electrode and the substrate. This dielectric layer enables electrical coupling necessary for plasma generation at the substrate end while preventing direct electrical contact that would cause unwanted effects, thus resolving the contradiction between plasma effectiveness and device complexity.
3Ease of operation
If the substrate supporting member excludes the end part, then plasma processing access is improved, but substrate support stability is reduced
Solution Approach 1:
The substrate supporting member is designed with an asymmetric configuration where the central region provides stable support while the end region is excluded to allow plasma access. This asymmetric design balances the conflicting requirements of support stability and plasma processing accessibility by providing support only where structurally necessary.
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 apparatus effectively generates plasma locally at the end part of the substrate, allowing for efficient removal of deposits like polymers, thereby preventing particle formation in subsequent processes and enhancing the overall plasma processing effectiveness.
Implementation Method 1
a side ground electrode provided at a side of the substrate supported by the substrate supporting member so as to be close to the substrate to such an extent that an electrical coupling is formed between an end surface of the substrate and the side ground electrode
Implementation Method 2
an electrical coupling is formed between an end surface of the substrate and the side ground electrode
Implementation Method 3
a high frequency power being applied to the substrate supporting member and at least a side of the substrate supporting member being composed of a dielectric
Data Source
AI summary
This plasma processing apparatus for performing plasma processing on an end part of a substrate includes a processing container, a substrate supporting member configured to support a portion of the substrate and to which a high frequency power is applied, at least a side of the substrate supporting member being composed of a dielectric, an opposing dielectric member composed of a dielectric and disposed to oppose the substrate supporting member, and a gas supply configured to supply a processing gas for generating plasma on at least the end part of the substrate. The plasma processing apparatus further includes a side ground electrode provided at a side of the substrate so as to be close to the substrate to such an extent that an electrical coupling is formed between an end surface of the substrate and the side ground electrode, the side ground electrode having a ground potential.