Lithography system, control system and device manufacturing method

A method of manufacturing a device using a lithography system comprising:

• predicting a performance criterion of the formation of a pattern on a substrate by the lithography system, based on an operating condition of the lithography system, wherein the operating condition of the lithography system used to determine the prediction of the performance criterion includes at least one selected from the following:
• focal plane error, or aberration error, or stray radiation, or numerical aperture of a projection system, or servo error of a stage configured to hold a patterning device, or servo error of a stage configured to hold a substrate, or nominal shape of an illumination pupil of an illuminator, or shape variations through a slit of an illumination pupil of an illuminator, or intensity variations through a slit of an illumination pupil of an illuminator, or polarization uniformity across an illumination pupil of an illuminator, or dose of radiation in each exposure, or nature of a resist applied to the substrate;
• exposing a pattern of radiation on the substrate;
• measuring a performance criterion of the formation of the pattern on the substrate by the lithography system, the measured performance criterion corresponding to the predicted performance criterion;
• and
• comparing the predicted performance criterion with the corresponding measured performance criterion,
• wherein the subsequent control of the lithography system is regulated by the difference in the predicted performance criterion and the corresponding measured performance criterion.

A computer readable media containing program instructions to control a lithography system, the program instructions comprising:

• a performance prediction section, configured to predict a performance criterion of the formation of a pattern on a substrate by the lithography system based on an operating condition of the lithography system;
• a performance measurement section, configured to measure a performance criterion of the formation of the pattern on the substrate by the lithography system, the measured performance criterion corresponding to the predicted performance criterion;
• a comparison section, configured to compare the predicted performance criterion with the corresponding measured performance criterion;
• and
• a process control section, configured to control the lithography system,
• wherein the subsequent control of the lithography system by the process control section is regulated by the difference in the predicted performance criterion and the corresponding measured performance criterion determined by the comparison section, wherein if the rate of change of the difference exceeds a respective threshold, at least one of the following occurs:
• a notification is issued, corrective action is taken, corrective action is scheduled, or the operation of at least part of the lithography system is suspended.