Harmonic derived arc detector
First Claim
Patent Images
1. An arc detection system, comprising:
- a radio frequency (RF) signal probe that senses a RF signal at an input of a RF plasma chamber and that generates a signal based on at least one of the voltage, current, and power of the RF signal; and
a signal analyzer that receives the signal, monitors the signal for frequency components at a harmonic frequency of a fundamental frequency of the RF signal, and that generates an output signal based on the frequency components wherein the output signal indicates that an arc is occurring in the RF plasma chamber;
wherein the signal analyzer compares an amplitude of the signal to a first predetermined amplitude, compares a rate of change of the signal to a predetermined rate of change, and generates the output signal when the rate of change of the signal exceeds the predetermined rate of change and the amplitude of the signal is between the first predetermined amplitude and a second predetermined amplitude.
9 Assignments
0 Petitions
Accused Products
Abstract
An arc detection system includes a radio frequency (RF) signal probe that senses a RF signal at an input of a RF plasma chamber and that generates a signal based on at least one of the voltage, current, and power of the RF signal. A signal analyzer receives the signal, monitors the signal for frequency components that have a frequency greater than or equal to a fundamental frequency of the RF signal, and generates an output signal based on the frequency components. The output signal indicates that an arc is occurring in the RF plasma chamber.
109 Citations
33 Claims
-
1. An arc detection system, comprising:
-
a radio frequency (RF) signal probe that senses a RF signal at an input of a RF plasma chamber and that generates a signal based on at least one of the voltage, current, and power of the RF signal; and a signal analyzer that receives the signal, monitors the signal for frequency components at a harmonic frequency of a fundamental frequency of the RF signal, and that generates an output signal based on the frequency components wherein the output signal indicates that an arc is occurring in the RF plasma chamber; wherein the signal analyzer compares an amplitude of the signal to a first predetermined amplitude, compares a rate of change of the signal to a predetermined rate of change, and generates the output signal when the rate of change of the signal exceeds the predetermined rate of change and the amplitude of the signal is between the first predetermined amplitude and a second predetermined amplitude. - View Dependent Claims (2, 3, 4, 5, 6)
-
-
7. An arc detection system, comprising:
-
a radio frequency (RF) signal probe that senses a RF signal at an input of a RF plasma chamber and that generates a signal based on at least one of the voltage, current, and power of the RF signal; an analog to digital converter that converts the signal to a digital signal; and a signal analyzer that receives the digital signal, monitors the digital signal for frequency components of the RF signal at a harmonic frequency of a fundamental frequency of the RF signal, and that generates an output signal based on the frequency components wherein the output signal indicates that an arc is occurring in the RF plasma chamber; wherein the signal analyzer compares an amplitude of the RF signal, as indicated by the digital signal, to a predetermined threshold, compares a rate of change of the RF signal, as indicated by the digital signal, to a predetermined rate of change;
generates the output signal when the rate of change of the RF signal exceeds the predetermined rate of change and the RF signal amplitude is between the first predetermined threshold and a second predetermined threshold. - View Dependent Claims (8, 9, 10, 11, 12, 13, 14, 15, 16, 17)
-
-
18. A method of detecting an arc in a RF plasma processing system, comprising:
-
sensing a RF signal at an input of a RF plasma chamber; generating a signal based on at least one of the voltage, current, and power of the RF signal; monitoring the signal for frequency components at a harmonic frequency of a selected fundamental frequency within the RF signal; generating an output signal based on the frequency components wherein the output signal indicates that an arc is occurring in the RF plasma chamber; comparing an amplitude of the signal to a first predetermined threshold; comparing a rate of change of the signal to a predetermined rate of change; and generating the output signal occurs when the rate of change of the signal exceeds the predetermined rate of change and the amplitude of the signal is between the first predetermined threshold and a second predetermined amplitude. - View Dependent Claims (19, 20, 21, 22)
-
-
23. A method of detecting an arc in a RF plasma processing system, comprising:
-
sensing a RF signal at an input of a RF plasma chamber; generating a signal based on at least one of the voltage, current, and power of the RF signal; converting the signal to a digital signal; monitoring the digital signal for frequency components of the RF signal at a harmonic frequency a fundamental frequency of the RF signal; generating an output signal based on the frequency components wherein the output signal indicates that an arc is occurring in the RF plasma chamber; and comparing an amplitude of the RF signal, as indicated by the digital signal, to a predetermined threshold; comparing a rate of change of the RF signal, as indicated by the digital signal, to a predetermined rate of change; and generating the output signal when the rate of change of the RF signal exceeds the predetermined rate of change and the RF signal amplitude is between the first predetermined threshold and a second predetermined threshold. - View Dependent Claims (24, 25, 26, 27, 28, 29, 30, 31, 32, 33)
-
Specification