Scanning Electron Microscope (SEM) has been typical methods for measuring CD of nanopatterns until ArF process was introduced. However in case of ArF process, this method has serious drawback such as shrinkage of organic material by the irradiation of high-energy electron beam. The optical scatterometry system is considered to be promising method for measuring CD due to no damage on organic materials. Sub-80nm node gate was selected because of its measurement stability. CD, profile and thickness are compared with those measured by CD-SEM, cress-section SEM. The correlation degree is shown as GOF, R2, and Profile. Based on merit of speed, easiness and accurate measurement, optical CD method has been applied to CD uniformity. CD uniformity measured by OCD was very similar to that measured by SEM on gate pattern. Based on this result, OCD was applied for the improvement of CD uniformity combined with ASML's does-mapper in technology. We investigated the variation of thickness of organic BARC over topology of various size line and space patterned poly-Si by OCD.
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