Inductive Coil Structure with Auxiliary Capacitors for ICP Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional inductively-coupled plasma (ICP) generation systems suffer from low discharge stability and plasma density, particularly at atmospheric or high pressures, due to issues with voltage increase and capacitive-coupling components, which lead to damage of dielectric discharge tubes and inefficient power transmission.
Innovation Solution
The proposed solution involves an inductive coil structure with a voltage division structure, including series-connected inductive coils and auxiliary capacitors, which distribute voltage and reduce impedance, allowing for stable and efficient ICP generation at higher pressures by maintaining a resonance frequency with the driving frequency, thus minimizing capacitive coupling and preventing dielectric tube damage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If the winding number of the inductive coil is increased to improve plasma density, then the voltage increases causing dielectric tube damage, but the plasma density improves
Solution Approach 1:
The inductive coil is divided into multiple sections with capacitors inserted between them, creating a segmented structure. This segmentation allows the total voltage to be distributed across multiple capacitor-inductor units, preventing excessive voltage at any single point while maintaining the required plasma density through increased overall winding number.
Solution Approach 2:
Capacitors are introduced as intermediary elements between coil windings. These capacitors act as voltage distribution mediators, storing and releasing electrical energy to maintain stable voltage levels across the coil structure, thereby enabling high winding numbers without causing dielectric breakdown.
2Reliability
If the inductive coil structure is modified to suppress capacitive coupling, then discharge stability improves, but device complexity increases
Solution Approach 1:
The coil is segmented into discrete winding sections separated by capacitors. This segmentation creates independent resonant circuits that can be tuned to operate at the same frequency, reducing capacitive coupling between sections while maintaining overall system functionality with a relatively simple modular structure.
3Productivity
If the number of windings per unit length is increased to improve plasma generation efficiency, then the voltage increases causing parasitic discharges, but the plasma generation efficiency improves
Solution Approach 1:
By segmenting the coil into multiple sections with capacitors, the patent enables increased total windings per unit length while distributing the voltage stress. Each segment operates at lower voltage, preventing parasitic discharges even as the overall winding density increases to improve plasma generation efficiency.
Solution Approach 2:
The patent changes the electrical parameters of the coil system by introducing capacitors, which alters the voltage distribution characteristics. This parameter change allows the system to operate with higher winding densities without reaching the voltage threshold that causes parasitic discharges, thereby improving plasma generation 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
This configuration enhances discharge stability and efficiency, enabling ICP generation at higher pressures without damaging the dielectric discharge tube, even at higher power levels, and allows for improved plasma density and reduced parasitic discharges.
Implementation Method 1
an inductive coil structure, which is configured to stably generate inductively-coupled plasma
Implementation Method 2
auxiliary capacitors, which are respectively provided between adjacent ones of the inductive coils to distribute a voltage applied to the inductive coils
Implementation Method 3
an RF power supply configured to provide positive and negative powers having opposite phases, to respectively supply positive and negative powers of RF power to both ends of the first inductive coil structure
Implementation Method 4
a dielectric tube extending in a length direction
Data Source
AI summary
An inductively-coupled plasma (ICP) generation system may include a dielectric tube, a first inductive coil structure to enclose the dielectric tube, an RF power supply, a first main capacitor between a positive output terminal of the RF power supply and one end of the first inductive coil structure, and a second main capacitor between a negative output terminal of the RF power supply and an opposite end of the first inductive coil structure. The first inductive coil structure may include inductive coils connected in series to each other and placed at different layers, the inductive coils having at least one turn at each layer, and auxiliary capacitors, which are respectively provided between adjacent ones of the inductive coils to distribute a voltage applied to the inductive coils.