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We used the SVGL Micrascan 193 at International Sematech to evaluate four Sumitomo resists on four BARC products. The Sumitomo resists reviewed were PAR 710A35 and PAR 71835 for sense lines, PAR 710A2 and PAR 722A3 for contact holes. We evaluated isolated line performance using PAR 715A25 and PAR 710A35. The BARC products evaluated were SiON and three commercially avaialable organic systems. BARC reflectivity curves were generated for each of the BARC chemistries to determine proper BARC thicknesses. Following resist apply and bake processing, the wafers were subjected to ArF open frame exposures on an SVGL Micrascan 193. After post exposure bake and development, the energies required to clear the exposed region(E0) were noted. Film thickness versus E0 value was plotted to generate swing curves and resultant EMIN and EMAX resist thickness points. Dense line performance was evaluated with quadrapole illumination (0.7/0.1). Isolated line and contact hole performance was evaluated using 0.6NA/0.6PC illumination, with the exception of PAR 710A35, where we evaluated isolated line performance of PAR 710A35 using quadrapole illumination (0.7/0.1). All evaluations were made at a consistent point in the illumination slot and scan of a 26 x 34mm field, each field containing through focus conditions at doses varying 5% for each respective field. The dense and isolated line features were stepped through focus in fifteen 70nm steps, while the contacts were stepped eleven times in 100nm micro steps. The samples were prepared with 3.0nm of AuPd. The critical dimensions (CD) targeted were 120nm for dense lines, 120nm and lower for isolated lines, and 150nm for contact holes. Focus auto calibration and illumination uniformity calibrations were run before the actual exposure of the wafers to ensure the tool was within specifications. Wafers were exposed to determine the nominal exposure dose. Wafers for cross section SEM were exposed and broken to evaluate footing, line width and depth of focus (DOF) performance.
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