Applied physics
No. 4, 1997

Resolution of the optical systems and problem
of rendering of the mminnimal features

A.V. Nikitin
The State Scientifical Researh Institute of Physics Problem, Moscow, Russia

   In the paper the relationship between resolution of the projestion optical systems and the sizes of the minimal features in the image formed by this system is analysed in details. The two discussed in modern publications researh and development ways for creating the features with sizes less than the system resolution limit are examined. These ways are: a - the creating the photolithographic masks with optimal amplititude-phase distributions; b - using the off-axis illumination of the objects. It is show that these ways are identical in essence, but differ only in details of their technical realization. It is estimated that in both cases it is possible to realize the features of the special shapes with sizes less than the system resolution limit (the supersmall features) by the controlled interference of the ligt waves in the image plane. In this case, however, the image as a whote will distorted, but the optical system resolution will not be changed. The examples of the practical arrangement conditions of experiments for the obtaing of the supersmall features both on the optimal mask way, and the using of the off-axis illumination way are given.

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