Tunable Showerhead and Liner Impedance for Plasma Uniformity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Non-symmetries and plasma non-linearity in processing chambers during etching or plasma-assisted chemical vapor deposition lead to non-uniform etch rates and deposition on substrates.
Innovation Solution
A process chamber with tunable components, including a showerhead and chamber liner, each coupled with impedance circuits and controllers to independently control their impedances, allowing for precise plasma distribution and uniform processing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If traditional fixed-impedance showerhead and liner are used, then device structure is simple, but plasma distribution is non-uniform due to chamber non-symmetries and plasma non-linearity
Solution Approach 1:
The patent applies dynamics by making the showerhead and chamber liner impedances adjustable rather than fixed. Impedance tuning circuits with variable capacitors allow real-time modification of electrical impedance to compensate for plasma non-linearity and chamber non-symmetries, transforming static components into dynamically controllable elements that adapt plasma distribution.
Solution Approach 2:
The patent implements parameter changes by modifying electrical impedance parameters of the showerhead and chamber liner through tuning circuits. By adjusting capacitance values in the impedance tuning circuits, the electrical characteristics of these components are changed to optimize plasma uniformity, directly addressing the non-uniform plasma distribution problem.
2Ease of operation
If independent impedance tuning of showerhead and liner is implemented, then plasma distribution control is improved, but device complexity increases
Solution Approach 1:
The patent applies segmentation by dividing the impedance control into separate independent circuits for the showerhead and chamber liner. Each component has its own tuning circuit with independent variable capacitors, allowing separate optimization of each component's impedance without affecting the other, thus simplifying the control strategy while improving plasma uniformity.
Solution Approach 2:
The patent implements feedback through a controller that receives signals from plasma uniformity sensors and automatically adjusts the impedance tuning circuits. This closed-loop feedback system monitors plasma distribution and makes real-time impedance adjustments to maintain uniform plasma, reducing manual intervention 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 solution enables improved control over plasma distribution, addressing non-uniformities in etching and deposition, resulting in enhanced uniformity and efficiency in substrate processing.
Implementation Method 1
a first impedance circuit coupled to the showerhead to tune an impedance of the showerhead; a second impedance circuit coupled to the chamber liner to tune an impedance of the chamber liner
Data Source
AI summary
Process chambers having a tunable showerhead and a tunable liner are disclosed herein. In some embodiments, a processing chamber includes a showerhead; a chamber liner; a first impedance circuit coupled to the showerhead to tune an impedance of the showerhead; a second impedance circuit coupled to the chamber liner to tune an impedance of the chamber liner; and a controller coupled to the first and second impedance circuits to control relative impedances of the showerhead and the chamber liner.