Process Control Method For Lithographically Processed Semiconductor Devices

Photoresist layers are exposed to an exposure beam by using an exposure tool assembly, wherein the photoresist layers coat semiconductor substrates and wherein for each exposure a current exposure parameter set is used that includes at least a defocus value and an exposure dose. The exposed photoresist layers are developed, wherein resist patterns are formed from the photoresist layers. Feature characteristics in the resist patterns and/or in substrate patterns derived from the resist patterns are measured. The current exposure parameter set is updated in response to deviations of the measured feature characteristics from target feature characteristics. De-corrected feature characteristics of hypothetical resist patterns are estimated, which would be formed without updating the exposure parameter set. In response to information obtained from the de-corrected feature characteristics the measurement strategy for the feature characteristics may be changed or the current exposure parameter set may be updated.