Patent ID: 8433434

Claim:
A method for processing control, the method comprising: diagnosing a chamber of a processing tool that processes a wafer to identify a key chamber parameter, the diagnosing using a predicted result of the wafer, wherein the diagnosing the chamber comprises: predicting the result of the wafer; correlating a chamber parameter data set to a residual data set to obtain a coefficient of correlation for the chamber parameter, wherein the chamber parameter data set comprises chamber data points each relating to either one of historical wafers or the wafer, and wherein the residual data set comprises error data points each relating to either one of the historical wafers or the wafer; identifying a non-key chamber parameter if a coefficient of correlation is less than a first limit; defining a chamber parameter stable range based on each of the error data points that has an absolute value less than a target; defining a chamber parameter unstable range based on each of the error data points that has an absolute value equal to or greater than the target; analyzing a difference between the chamber parameter stable range and the chamber parameter unstable range; and identifying the key chamber parameter if the difference between the chamber parameter stable range and the chamber parameter unstable range is within a second limit; and controlling the chamber based on the key chamber parameter if the key chamber parameter can be controlled, or compensating a prediction model by changing to a secondary prediction model if the key chamber parameter is passive.