RF Power Allocation Circuit for Fast Plasma Distribution Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing plasma processing technologies struggle to control plasma distribution at high speeds, especially in atomic layer deposition (ALD) processes with short processing times, due to the difficulty in rapidly changing the ratio of radio frequency powers between electrodes using conventional methods.
Innovation Solution
A plasma processing apparatus and method that utilizes an allocation setting unit with series circuits and switching elements to control the impedance and power allocation between electrodes, allowing for rapid adjustment of plasma distribution through a control device.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a variable capacitor with a stepper motor is used to control the ratio of radio frequency powers, then the plasma distribution can be controlled to a desired distribution, but the control speed is slow
Solution Approach 1:
The patent replaces the mechanical stepper motor system with an electronic switching system. Instead of mechanically adjusting the variable capacitor, the invention uses switching elements (transistors or diodes) controlled by a control device to electronically adjust the impedance and distribute radio frequency power. This substitution eliminates mechanical inertia and enables rapid, precise control of plasma distribution without the speed limitations of motor-driven mechanisms.
2Productivity
If the processing time is shortened for high productivity, then the throughput increases, but the plasma distribution becomes difficult to control uniformly
Solution Approach 1:
The patent implements dynamic control of plasma distribution by enabling real-time adjustment of radio frequency power allocation during the processing cycle. The switching elements can rapidly change impedance values in response to process conditions, allowing the system to maintain uniform plasma distribution even when processing times are shortened for high productivity. This dynamic adaptability ensures quality control is not compromised by increased throughput demands.
Solution Approach 2:
The invention changes the electrical parameters (impedance values) of the impedance circuits through electronic switching to optimize plasma distribution. By adjusting the resistance and reactance values dynamically based on processing requirements, the system can achieve uniform plasma distribution across the substrate regardless of processing duration, thereby maintaining manufacturing precision while enabling high productivity modes.
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 precise and rapid control of plasma distribution, enhancing the uniformity and efficiency of plasma processing, particularly in ALD, by adjusting power allocations and impedances to match desired plasma distributions.
Implementation Method 1
a power supply source configured to supply the radio frequency powers to the first electrodes to generate plasma between the first electrodes and the second electrode
Data Source
AI summary
In a plasma processing apparatus, a processing chamber is provided. First electrodes are disposed inside the processing chamber and supplied with radio frequency powers. The second electrode is disposed inside the processing chamber and functions as a counter electrode for the first electrodes. The power supply source supplies radio frequency powers to the first electrodes to generate plasma between the first electrodes and the second electrode and process a target object using the plasma. The allocation setting unit is disposed between the power supply source and at least one of the first electrodes to set power allocations of the radio frequency powers to be supplied to the first electrodes. Further, the allocation setting unit has series circuits in each of which an impedance circuit and a switching element are connected in series. The series circuits are connected in parallel. The control device controls the switching elements in the series circuits.