| Popis: |
Lithographic scaling entails continuously increasing resolution while at the same time improving the tolerance control on the printed images. Typically, this has been done by using shorter actinic wavelengths, increasing numerical aperture, compensating reticle patterns and similar methods that serve to enhance the fidelity of the aerial image. In some case, this scaling has been achieved by altering the method of image formation, such as with the use of alternating phase shift reticles, in which the width of the aerial image is established by phase interference rather than of a diffraction-limited process of passing light through a dark masking pattern. This paper describes development of a resist material that provides a new way to scale lithographic patterns, one similar to alternating phase shift lithography in the sense that it prints the edge of an aerial image rather than the entire image as a single pattern. Because the edge of the aerial image is of higher resolution, with smaller components of tolerance than the entire image, this type of resist may provide a new method of scaling. |
