Passive capacitively-coupled electrostatic (CCE) probe method for detecting plasma instabilities in a plasma processing chamber

摘要

A method for detecting plasma instability within a processing chamber of a plasma processing system during substrate processing is provided. The method includes collecting a set of process data, the process data including a set of induced current signals flowing through a measuring capacitor. The method further includes converting the set of induced current signals into a set of analog voltage signals and converting the set of analog voltage signals into a set of digital signals. The method also includes analyzing the set of digital signals to detect high frequency perturbations, the high frequency perturbations indicating the plasma instability.

主权项

1. A method for detecting plasma instability within a processing chamber of a plasma processing system during substrate processing, comprising:
collecting a set of process data including a set of induced current signals, wherein the set of induced current signals corresponds to current induced to flow through a measuring capacitor by plasma within the processing chamber, and wherein a first plate of the measuring capacitor is connected to a plasma-facing sensor and the induced current signals are measured at a second plate of the measuring capacitor; converting said set of induced current signals into a set of analog voltage signals; converting said set of analog voltage signals into a set of digital signals; and analyzing said set of digital signals to detect high frequency perturbations, said high frequency perturbations indicating said plasma instability.