| abstract |
The process state of a chamber after a maintenance procedure can be monitored in-situ in order to ensure that the chamber is ready for processing, while minimizing waste and downtime due to aftereffects of the maintenance procedure. The composition of a bulk plasma in a process chamber can be analyzed using an analytical tool to capture the emission spectrum of the plasma. The spectrum can be analyzed to generate a model of the current chamber conditions, which can be compared to a model of ideal chamber conditions using a statistical analysis approach such as multivariate primary component analysis. If the current and ideal models match to within a set confidence level, the chamber conditions are acceptable for processing devices, and any processing of cycling workpieces or other plasma-cleansing processes can be stopped. |