Parallel-Plate Plasma Measurement Using RF Mixed-Wave Analysis
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current substrate processing technologies face challenges in accurately measuring and controlling plasma state parameters like density and temperature during semiconductor and flat panel display manufacturing, which are crucial for effective film formation and etching processes.
Innovation Solution
A substrate processing apparatus utilizing parallel flat-plate electrodes with distinct radio-frequency power supplies to generate and control plasma, along with an analyzer to measure and analyze mixed waves from these powers, allowing for precise regulation of plasma state based on power level measurements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a probe part is arranged inside the chamber to measure plasma absorption frequency, then plasma density can be obtained, but the measurement accuracy is insufficient for precise plasma state control
Solution Approach 1:
The patent replaces the mechanical probe-based measurement system with an electromagnetic wave-based measurement system. By using radio-frequency power supplies to generate plasma and an analyzer to measure mixed waves, the system achieves more accurate plasma state measurement without the limitations of physical probe insertion into the chamber.
Solution Approach 2:
The patent introduces mixed waves as an intermediary medium to indirectly measure plasma state parameters. Instead of directly probing the plasma with physical sensors, the system uses electromagnetic waves that interact with the plasma, and the analyzer measures the characteristics of these mixed waves to determine plasma density and temperature with higher precision.
2Reliability
If radio-frequency power is supplied to generate plasma, then highly-reactive active species are obtained at low temperature, but precise control of plasma density and temperature is difficult
Solution Approach 1:
The patent implements a feedback control system where the analyzer continuously measures the mixed waves generated by the plasma, determines the plasma state parameters (density and temperature), and this information is used to adjust the radio-frequency power supply settings. This closed-loop feedback enables precise control of plasma parameters while maintaining the benefits of low-temperature highly-reactive plasma.
Solution Approach 2:
The radio-frequency power supply system serves multiple functions: it generates the plasma, sustains the plasma, and its output is modulated based on feedback from plasma measurements. The system can dynamically adjust power levels to maintain optimal plasma conditions for different processing requirements, making the plasma generation process both reliable and easy to control.
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
Enables accurate determination and adjustment of plasma density and temperature, ensuring sustainable film formation processes by analyzing mixed waves and adjusting power levels accordingly, thereby improving processing efficiency and quality.
Implementation Method 1
a first radio-frequency power supply connected to either the metal-made shower head or the metal-made stage and configured to supply first radio-frequency power to generate a plasma of the reaction gas between the parallel flat-plate electrodes
Implementation Method 2
a second radio-frequency power supply configured to supply second radio-frequency power to the plasma, the second radio-frequency power having a frequency different from a frequency of the first radio-frequency power
Implementation Method 3
an analyzer configured to acquire a mixed wave of the first radio-frequency power and the second radio-frequency power, which is obtained by the generation of the plasma, and to analyze a state of the plasma based on a result obtained by measuring a power level of the mixed wave
Data Source
AI summary
A substrate processing apparatus includes: a processing container having a processing space; a gas supply mechanism for supplying a reaction gas to the processing space; a shower head which is arranged in the processing space and discharges the reaction gas into the processing space; a stage which is arranged to face the shower head in the processing space, the stage and the shower head being configured to constitute parallel flat-plate electrodes; a first radio-frequency power supply which is connected to either the shower head or the stage and supplies first radio-frequency power to generate a plasma of the reaction gas between the electrodes; a second radio-frequency power supply for supplying second radio-frequency power to the plasma; and an analyzer for acquiring a mixed wave of the first and second radio-frequency powers and analyzing a state of the plasma based on a result of measuring a power level of the mixed wave.