RF Power Source Voltage Divider Switching for Dual Cathode Plasma

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The existing radio frequency power source devices for dual cathodes systems face challenges in downsizing and cost reduction due to the need for two separate power sources, and they struggle to deliver voltage outputs with different values (high and low) as required for plasma ignition and maintenance, resulting in insufficient voltage for plasma ignition and voltage reduction issues.

Innovation Solution

A radio frequency power source device with a voltage divider configuration that uses capacitive elements connected in series, allowing for switching between high and low voltage outputs by changing the connection state with respect to ground potential, enabling selective delivery of high or low voltage values without reducing the output voltage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If two separate radio frequency power sources are used for dual cathodes, then each electrode can receive appropriate voltage, but device size and production cost increase

Engineering Contradiction:
Improvevoltage delivery reliabilityVSAvoiddevice complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent segments the voltage delivery function by using a single radio frequency power source combined with a voltage divider circuit that includes switching elements. This allows the system to deliver different voltages to different electrodes through circuit segmentation rather than requiring separate power sources, thereby reducing device complexity while maintaining reliability

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent makes a single radio frequency power source universal by combining it with a voltage divider and switching circuitry that enables it to deliver multiple voltage levels to different electrodes. This multi-functionality approach allows one power source to replace what would traditionally require two separate power sources, reducing overall device complexity

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Adaptability or versatility

If voltage divider is used to deliver different voltage values, then plasma ignition and maintenance can be supported, but voltage reduction occurs at output ends

Engineering Contradiction:
Improvevoltage value adaptabilityVSAvoidoutput voltage
Core Design Contradiction:
Adaptability or versatilityVSPower

Solution Approach 1:

The patent applies dynamics by using switching elements that can dynamically change the connection state of the voltage divider circuit. This allows the system to switch between different voltage division ratios in real-time, enabling adaptive voltage delivery for different operational phases (ignition and maintenance) while managing voltage levels appropriately

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent employs periodic action through time-sequential voltage delivery, where the switching circuit alternates between different voltage division configurations during plasma ignition and maintenance phases. This periodic switching allows the system to deliver high voltage during ignition and appropriate lower voltage during maintenance, addressing both requirements through temporal separation

Inventive Principle:
Principle #19Periodic action

3Adaptability or versatility

If switching between high and low voltage outputs is implemented, then plasma ignition and maintenance requirements are met, but device complexity increases

Engineering Contradiction:
Improvevoltage switching capabilityVSAvoiddevice complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent merges the voltage switching function with the existing voltage divider circuit by integrating switching elements directly into the voltage division structure. This combination approach allows voltage switching capability to be achieved without adding completely separate switching circuits, thereby limiting the increase in device complexity while still providing the necessary adaptability

Inventive Principle:
Principle #5Merging (Combining)

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 allows for the delivery of different voltage values as needed, preventing voltage reduction and ensuring sufficient high voltage for plasma ignition while maintaining low voltage for plasma maintenance, thus addressing the limitations of existing systems.

Implementation Method 1

a voltage divider 4 for dividing the radio frequency voltage delivered from the radio frequency output circuit 3 into AC voltage outputs in antiphase with each other with respect to a ground potential

Methodology Applied
Scientific EffectCapacitance: Capacitance

Data Source

PatentEP3236718B1Radio frequency power source device, and power source for dual cathodes
Publication Date: 2019.05.08 KYOSAN ELECTRIC MFG CO LTD
  • EP3236718B1 patent drawingFigure 1A~1C
  • EP3236718B1 patent drawingFigure 2A~2D
  • EP3236718B1 patent drawingFigure 3A~3C

AI summary

In radio frequency power source devices for delivering AC voltage outputs in antiphase with each other, having a configuration to divide the voltage output from a radio frequency output circuit into two, it is not possible to perform switching as appropriate, between different voltage values, high voltage and low voltage, resulting in that the voltage at an output end is reduced to have a half peak value of the voltage output of the radio frequency output circuit. There is provided a radio frequency power source device configured to change a voltage ratio between two output end voltages, by switching a connection state of a voltage divider that divides the radio frequency voltage, in such a manner that the radio frequency voltage is divided into voltage outputs in antiphase with each other with respect to ground potential, and high voltage and low voltage are delivered in switching manner. Switching of the connection state in the voltage divider enables selective delivery of voltage having different values, high voltage or low voltage, and by selecting and delivering high voltage for the time high voltage is required, reduction of the voltage output from the radio frequency output circuit is prevented.