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The introduction of resolution enhancement techniques (RETs) and higher numerical aperture (NA) scanners has pushed the capability of 248nm (DUV) processes to below 130nm. This extension of DUV technology has made the decision to insert 193nm difficult. The decision to either extend the current DUV processes or to change to 193nm will depend on several things: mask costs, tool costs, material availability and photoresist performance. The focus of this paper is on photoresist performance. The process latitudes of advanced DUV photoresists are compared to the latest generation of 193nm resists and simulation is used to estimate the performance obtained on the next generation scanners. This paper examines resist process latitude at several feature sizes to determine the strengths and weaknesses of each platform. The feature sizes to be examined include 130nm, 120nm and 110nm with a pitch ratio of 1:1 Lines/Spaces. The resists are processed on the appropriate anti-reflectant and a resist film thickness of approximately 3,000 angstrom is used. The measured lithographic response will be the individual process windows. The examination of each platform's performance will clarify the differences between the two resists on current scanners and estimate the differences on the next generation scanners. The results show experimentally that the current 193nm resist has slightly better process latitudes than the DUV resist for 1:1 Line/Spaces below 130nm. The estimation of performance on the next generation higher NA scanners indicate that the DUV resist will have better performance than the current 193nm resist. However, when the 193nm resists reach the same maturity as the DUV resist and respond to the aerial images accordingly, the 193nm resist will have better process latitude. While few resolution enhancement techniques are used in the experiments, the results do provide a piece of information required to decide between DUV and 193nm.
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