An Analysis Of The Relevance To Linewidth Control Of Various Aerial Image Characteristics

The results of a simulation study into various aerial image characteristics are presented, and these characteristics are shown to relate to features of the simulated developed resist profile. The results were obtained using the simulation program SPESA, and a related program VARYIM: - A novel method of presenting image characteristics over the full line/spacewidth domain will be introduced. - Relative intensity at the mask edge and lateral position of an intensity threshold are shown to be good indicators for developed feature size. - Intensity gradient at the mask edge is an indicator for lattitude with respect to dose, development and focus variations. - Image contrast and the maximum and minimum image intensities are not very useful as indicators either for developed feature size or process latitude.