Staggered Faraday Shield Layout for Plasma Etching Power Transfer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The formation of copper by-products during etching processes in plasma processing devices leads to eddy currents, reducing power transfer efficiency and necessitating frequent chamber cleaning due to their attachment on the RF window and Faraday shield.
Innovation Solution
The implementation of staggered arrangements of first and second Faraday shields with alternating openings and portions, integrated with a dielectric window and supported by a cooling system, to prevent eddy current-induced electric field weakening.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If a Faraday shield is used to prevent eddy currents, then power transfer efficiency is improved, but the shield structure becomes complex requiring multiple components with openings and portions
Solution Approach 1:
The Faraday shield is divided into multiple segments (first Faraday shield and second Faraday shield) with alternating openings and portions. This segmentation allows the shield to effectively block eddy currents while maintaining plasma processing functionality, resolving the contradiction between energy efficiency and structural complexity by creating a modular design that achieves both goals.
2Reliability
If copper is used as the metal layer for low resistance, then electrical conductivity is improved, but copper by-products attach to the chamber interior requiring frequent cleaning
Solution Approach 1:
The patent converts the harmful effect of copper by-products into a beneficial configuration by designing the Faraday shield with alternating openings and portions that strategically block deposition zones. The shield structure utilizes the by-product deposition pattern to its advantage, preventing accumulation in critical areas while allowing controlled deposition in designated regions, thus reducing cleaning frequency while maintaining copper's electrical conductivity benefits.
3Loss of energy
If the Faraday shield is made solid to block eddy currents, then power transfer efficiency is improved, but plasma processing is hindered due to blocked plasma generation
Solution Approach 1:
The Faraday shield implements local quality by having alternating openings and portions rather than being uniformly solid or hollow. The portions block eddy currents in specific regions while openings allow plasma generation in other regions. This localized differentiation resolves the contradiction by enabling the shield to simultaneously improve power transfer efficiency where needed while maintaining plasma processing efficiency in designated areas.
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 effectively prevents the weakening of the induced electric field, reducing the need for frequent cleaning and maintaining efficient power transfer in plasma processing systems.
Implementation Method 1
a radio-frequency antenna connected to a radio-frequency power source
Implementation Method 2
a by-product of copper after reaction has low volatility, and may cause an issue of the by-produce of copper attaching onto an interior of a chamber of an etching device. When the by-product forms a film on an RF window and a Faraday shield, a power transfer efficiency into a plasma treatment space may be reduced due to eddy currents.
Data Source
AI summary
A plasma processing device according to an embodiment includes a chamber in which plasma process is performed, a radio frequency antenna connected to a radio frequency power source, a dielectric window disposed between the radio frequency antenna and the chamber, a first Faraday shield disposed on the chamber and including first portions and first openings, and a second Faraday shield disposed inside the chamber and including second portions and second openings. The first openings and the second openings may be alternately arranged in a staggered manner along a perpendicular direction.