Method of operating an optical imaging system, lithographic projection apparatus, device manufacturing method, and device manufactured thereby

摘要

The present invention provides a method of operating a lithographic projection apparatus including calculating a change in aberration effect in the projection system, due to heating effects, as a function of time, based on at least one set of predetermined parameters; and adjusting the lithographic projection apparatus to compensate for the calculated change in aberration effect. The parameters are obtained by a calibration operation, which may comprise a coarse calibration followed by at least one fine calibration. The coarse calibration yields a first estimate of at least a subset of the parameters. The estimate can be used as an input for a subsequent fine calibration. The calibration may also comprise a single fine calibration.