Abstract: A method of measuring a damaged structure formed on a semiconductor wafer using optical metrology includes directing an incident beam on the damaged structure. A diffracted beam is received from the damaged structure. The received diffracted beam is processed to determine a profile of an undamaged portion of the damaged structure and to measure an amount of dielectric damage of the damaged structure.

Abstract: A method of creating a library for measuring a plurality of damaged structures formed on a semiconductor wafer using optical metrology includes directing an incident beam on a first damaged structure. The first damaged structure was formed by modifying at least one process parameter in a dual damascene procedure. A diffracted beam is received from the first damaged structure. A measured diffraction signal is obtained based on the received diffracted beam. A first simulated diffraction signal is calculated. The first simulated diffraction signal corresponds to a hypothetical profile of the first damaged structure. The hypothetical profile includes an undamaged dielectric portion and a damaged dielectric portion. The measured diffraction signal is compared to the first simulated diffraction signal.

Abstract: A method for implementing FDC in an APC system including receiving an FDC model from memory; providing the FDC model to a process model calculation engine; computing a vector of predicted dependent process parameters using the process model calculation engine; receiving a process recipe comprising a set of recipe parameters, providing the process recipe to a process module; executing the process recipe to produce a vector of measured dependent process parameters; calculating a difference between the vector of predicted dependent process parameters and the vector of measured dependent process parameters; comparing the difference to a threshold value; and declaring a fault condition when the difference is greater than the threshold value.