Loading patent…
AssigneesJapan Science and Technology Corporation, Kumamoto Technopolice Foundation
InventorsMitsuo Yasaka, Masayoshi Takeshita
Estimating the term…
An anomalous arc discharge detection apparatus, including multiplicity of ultrasonic detectors placed at different sections of a plasma processing chamber such that an ultrasonic wave accompanying an anomalous discharge is detected by the ultrasonic detectors at different propagation times or with different delay times. The detected signals are compared with each other on the same time axis to obtain the maximum range of variation of the detected waveforms and the differences in delay time of the respective ultrasonic detectors. From the comparison of the maximum range of variation and the delay times of the ultrasonic detectors, the position of the source point, and the level as well, of the anomalous arc discharge are determined, which can be displayed on a monitor and utilized to issue an alarm if necessary. The position of the anomalous discharge may be obtained by an asymptotic approximation based on recursive calculations of the distances from the source point to the respective ultrasonic detectors using formulas which define the distances in terms of the delay times. This can be done using only four ultrasonic detectors arranged on the wall of the processing chamber. An AE sensor hold case is provided to accommodate an AE sensor. The hold sensor has a lower cover which has one end to be glued onto an appropriate position of the processing chamber, and an upper cover which pushes the AE sensor against the lower cover with an adequate pressure.
An anomalous arc discharge detection apparatus for use with a plasma processing equipment, comprising:
A method of detecting an anomalous arc discharge in a plasma processing equipment, comprising steps of:
An acoustic sensor hold case for accommodating an AE sensor, said hold case having one side to be glued onto an exterior of a processing chamber of a plasma processing equipment, said hold case comprising:
An anomalous arc discharge detection apparatus for use with a plasma processing equipment, comprising:
A plasma processing apparatus comprising:
A method for operating a plasma processing apparatus, the method comprising the steps of:
Dependencies are inferred from the claim text.