Abstract: Method and system for real-time in-situ interactive supervision of a step performed in a tool during semiconductor wafer fabrication process. The system includes a tool and the computer attached thereto, an end point detection controller, a database and a supervisor to supervise the whole wafer processing for that step. The controller is used to monitor a key process parameter of the step and is adapted to perform in-situ measurements. The database contains the evolution of said process parameter in normal operating conditions and in all the identified deviations. It further contains the history of the wafer until this step and a reference to the batch and process names for this step and the wafer identification number. At the end of the step, the important process parameters and any alert code are stored in the database to up-date the wafer history. This technique allows a total clusterized wafer fabrication process and prevents wafer rejection.