Patent ID: 8574795
Filing Date: 2013-11-05
Classification: G03F

Abstract:
1. A method comprising: obtaining a first reflective reticle having a pattern of structures corresponding to a target pattern for a wafer; exposing a first wafer covered with a first photoresist with the first reticle using a first dosage, or measuring and/or inspecting portions of the pattern of the first reticle and calculating and/or simulating corresponding portions of a first wafer pattern obtained with a predetermined first dosage; identifying variations in critical dimension (CD) between the exposed first wafer or the calculated or simulated first wafer pattern and the target pattern for different features in the target pattern; exposing a second wafer covered with a second photoresist with the first reticle using a second dosage; and correcting the CD variations by applying an additional exposure of the second wafer, to the second photoresist that is also exposed with the first reticle, before or after exposing the second photoresist with the first reticle.