Study of practical TAT reduction approaches for EUV flare correction

We introduce techniques of flare compensation for Extreme Ultraviolet Lithography that can reduce the calculation time of a flare map and flare correction. In the first approach, the range of a flare point spread function is divided into several regions and the size of meshes for the flare map in each region is selected. In the second approach, the size of the mask pattern is controlled by referring to the flare map in the mask-making process. In the third approach, dosage of each point in a mask corresponding to the flare map is modulated when transferring the mask pattern onto the resist. Use of these approaches in the proper combination is effective for TAT reduction and accuracy of the flare compensation.