High Frequency Measurement Apparatus Two-Stage Impedance Calibration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
High frequency measurement apparatuses in plasma processing systems face challenges in achieving accurate calibration due to temperature variations and phase difference errors, leading to reduced calibration accuracy and potential errors in monitoring and control of plasma processing parameters.
Innovation Solution
A high frequency measurement apparatus that performs two-stage calibration using basic and range-specific parameters based on impedance measurements from multiple reference loads, determining the impedance range in a Smith chart to apply precise calibration parameters for high accuracy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single calibration parameter is used for the entire impedance range, then the calibration process is simple, but the calibration accuracy deteriorates due to temperature variations and phase difference errors
Solution Approach 1:
The patent divides the impedance range into multiple regions (first impedance range and second impedance range) and applies different calibration parameters to each region. This segmentation allows the system to maintain high calibration accuracy across the entire impedance range by using region-specific parameters that are optimized for local temperature and phase difference characteristics, rather than using a single universal parameter that would compromise accuracy.
2Ease of operation
If calibration is performed without considering impedance range, then the measurement apparatus is simple to operate, but errors occur in monitoring and control of plasma processing parameters
Solution Approach 1:
The patent implements a dynamic calibration system that automatically determines which calibration parameter to use based on the measured impedance value. The system dynamically switches between the first calibration parameter (for the first impedance range) and the second calibration parameter (for the second impedance range) according to the operating conditions. This dynamic adaptation ensures reliable monitoring and control accuracy without requiring manual intervention or complex user input.
3Device complexity
If a single calibration parameter is used, then the device structure is simple, but temperature variations cause reduced calibration accuracy
Solution Approach 1:
The patent applies local quality by developing separate calibration parameters (first calibration parameter and second calibration parameter) that are specifically optimized for different impedance ranges. Each calibration parameter accounts for the local temperature and phase difference characteristics specific to its impedance range, allowing the system to maintain high calibration accuracy under temperature variations without requiring a completely complex recalibration system for every condition.
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
The solution enables high-accuracy calibration of voltage and current measurements, reducing errors and ensuring precise monitoring and control of plasma processing parameters, even under varying temperature conditions.
Implementation Method 1
The high frequency measurement apparatus 300 includes a capacitor capacitively coupled to a rod-shaped conductor for transmitting power to the plasma processing apparatus 400
Implementation Method 2
a coil magnetically coupled to the conductor, and detects a voltage v=√2·V·sin(ωt) with the capacitor and a current i=√2·I·sin(ωt+θ) with the coil
Data Source
AI summary
A method for calibrating voltage and current detected by a high frequency measurement apparatus is provided. By the method, a basic calibration parameter for a wide impedance range but with low accuracy and quadrant-specific calibration parameters for highly accurate calibration are calculated. This calculation is performed based, on values obtained by measuring three reference loads and true values of the reference loads. A first calibration unit of the apparatus calibrates the detected voltage and current by using the basic calibration parameter. A quadrant determining unit of the apparatus determines in which quadrant an impedance calculated from the calibrated voltage and current lies. A second calibration unit of the apparatus further calibrates the voltage and current by using a quadrant-specific calibration parameter corresponding to the determination result input from the quadrant determining unit.