Pulse RF Plasma Impedance Matching Across Multiple Pulse Periods
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional automatic frequency modulation technologies for impedance matching in pulse radio frequency plasma struggle to find matched frequencies for high pulse frequency plasma, resulting in difficulty in achieving impedance matching due to the narrow pulse width and high frequency jitter, limiting the number of frequency modulation cycles within a single pulse period.
Innovation Solution
A method that involves acquiring an initial frequency for a pulse period, sequentially searching for a matched frequency across multiple pulse periods, and using the modulation frequency from a previous pulse period as the initial frequency for subsequent pulses, effectively increasing the pulse width and allowing for impedance matching of high pulse frequency plasma.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If conventional automatic frequency modulation is used to find matched frequency within a single pulse period, then impedance matching can be achieved for medium or low pulse frequency plasma, but it fails to achieve impedance matching for high pulse frequency plasma due to insufficient number of frequency modulation cycles
Solution Approach 1:
The patent performs frequency modulation in advance across multiple pulse periods to determine the matched frequency before actual processing. By using the initial frequency of the first pulse period and sequentially modulating through subsequent pulse periods, the system pre-establishes the optimal frequency setting that will be applied to all pulse periods, thus resolving the contradiction between achieving adequate modulation cycles and maintaining high pulse frequency operation
Solution Approach 2:
The patent extends the frequency modulation process from a single pulse period dimension to multiple pulse periods. Instead of attempting to complete all frequency modulation within one pulse period, the system distributes the modulation process across multiple pulse periods (i-th pulse period and following candidate pulse periods), effectively adding a temporal dimension to the frequency search process
2Measurement precision
If frequency modulation is performed multiple times within a single pulse period to ensure accurate impedance matching, then matched frequency can be found for medium or low pulse frequency, but the narrow pulse width of high pulse frequency plasma limits the number of modulation cycles that can be performed
Solution Approach 1:
The system performs frequency modulation in advance across multiple pulse periods to determine the matched frequency before actual processing. By using the initial frequency of the first pulse period and sequentially modulating through subsequent pulse periods, the system pre-establishes the optimal frequency setting that will be applied to all pulse periods, thus resolving the contradiction between achieving adequate modulation cycles and maintaining high pulse frequency operation
Solution Approach 2:
The patent utilizes the periodic nature of pulse radio frequency plasma to perform frequency modulation across multiple pulse periods. By systematically modulating the frequency in each pulse period (i-th pulse period, (i+1)-th pulse period, etc.) and using the determined frequency from one period as the initial frequency for the next, the system accumulates sufficient modulation cycles while maintaining the original narrow pulse width characteristics
Data Source
AI summary
A method and a device for matching an impedance of pulse radio frequency plasma, and a plasma processing device are provided. In the method, a matched frequency is searched for sequentially in high radio frequency power phases of an i-th pulse period and multiple pulse periods following the i-th pulse period, and a specific modulation frequency determined in a process of searching for the matched frequency in a previous pulse is assigned as an initial frequency for the subsequent pulse. In this way, it is equivalent to increasing a width of a first radio frequency power phase of a pulse period. Therefore, by sequentially performing frequency modulation in the first radio frequency power phases of the multiple pulses, a matched frequency of pulse radio frequency plasma of a high pulse frequency can be found, thereby achieving impedance matching of plasma of a high pulse frequency.