Dielectric Plate Concentric Rings Plasma Uniformity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing plasma processing systems face challenges in achieving uniform plasma density across substrates, particularly in capacitively coupled plasma systems, where standing waves can disrupt the consistency of plasma processes.
Innovation Solution
Incorporating a dielectric plate with concentric rings or grooves of varying depth and width between the antenna and substrate holder to disrupt standing waves and promote uniform plasma generation, using features such as non-linear cross-sectional geometries and asymmetric or symmetrical patterns to optimize plasma uniformity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a conventional parallel plate plasma processing apparatus is used, then the system structure is simple, but standing waves form in the plasma space causing non-uniform plasma density
Solution Approach 1:
The dielectric plate is equipped with concentric rings or grooves that create locally varying electromagnetic field distributions. These structural features are positioned at specific locations to disrupt standing wave patterns and promote uniform plasma density across different regions of the plasma processing space.
Solution Approach 2:
A dielectric plate is introduced as an intermediary component between the upper electrode (antenna) and the lower electrode (substrate holder). This dielectric plate with specific structural features mediates the electromagnetic field interaction, transforming the field distribution to eliminate standing waves while maintaining the basic parallel plate structure.
2Manufacturing precision
If the dielectric plate thickness is increased to improve plasma uniformity, then standing wave disruption is enhanced, but the device complexity and energy loss increase
Solution Approach 1:
The thickness of the dielectric plate is optimized to a specific range (1mm to 30mm) to achieve effective standing wave disruption while minimizing electromagnetic energy loss. This parameter optimization balances the competing requirements of plasma uniformity and energy efficiency.
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 effectively generates uniform plasma density across the substrate, enhancing the consistency and efficiency of plasma processes like etching and deposition by minimizing standing wave formation and optimizing electromagnetic energy distribution.
Implementation Method 1
structural features that define a surface shape, on a surface that faces the plasma that assists in disrupting standing waves and/or prevents standing waves from forming within the plasma space
Implementation Method 2
optimizing electromagnetic energy distribution
Implementation Method 3
By applying power (e.g., microwave power, etc.) to at least one of the electrodes, a high-frequency electric field is formed between the electrodes
Implementation Method 4
resulting in a plasma of the processing gas being generated by means of the high-frequency electric field
Data Source
AI summary
Techniques disclosed herein include an apparatus for treating substrates with plasma generated within a plasma processing chamber. In one embodiment, dielectric plates, of a plasma system can include structural features configured to assist in generating a uniform plasma. Such structural features define a surface shape, on a surface that faces the plasma. Such structural features can include a set of concentric rings having an approximately non-linear cross section, and protrude into the surface of the dielectric plate. Such structural features may include feature depth, width, and periodic patterns that may vary depth and width along the concentric rings.