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Most advanced EB masks enhanced resolution are fabricated by CAR photo resist recently. The non-CAR resist would be unsatisfied with making the 0.1 micrometers -below advanced mask fabrication, even for the current 0.13 micrometers -generation high-end masks. Although CAR has the well-known advantages of high-contrast resolution and sensitivity, the complex process behaviors related with different CAR types need to be further investigated. Negative-type CAR ha been widely used to fabricate advanced masks in mask shops. However, positive-type CAR is not well developed to apply for production since it is not investigated yet very well. Therefore, there is an essential necessity to realize the discrepancy between positive and negative CAR. This paper describes the different process phenomenon existing between positive CAR and negative CAR. We made the comparison of difference between t them by conducting ga series of simple experiments: the dose sensitivity test was produced by writing the dose matrix pattern on masks with three different baking temperatures and measuring the selectivity by depth profiler. This selectivity defined here was the thickness of resist after developing, which is indicative of completeness of development, but not the etching selectivity. All process-regarding SEM pictures were captured to determine the best ADI pattern resolution and the related CD measurement was also performed by CD-SEM. From the OPC resolution and available CD information we would set an appropriate process condition for these CAR. After that, a critical layer pattern on the mask was designed to find the optimal process settings. Moreover, all defects were inspected with KLA Tencor Tera Star SLF27 inspection system to give the defect status of CAR. The test masks were written by JBX-9000MV E-beam writing system. The basic property of CAR process for mask fabrication was evaluated in this study.
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