As the semiconductor chip size continues to decrease, extreme ultra violet lithography (EUVL) is becoming a vital technology to achieve the high resolution patterning required for sub-7 nm node technologies. The patterning resolution of EUVL is highly dependent on the performance of EUV photoresists (PR) which can lead to variations in the patterning process and affects the overall quality of the semiconductor. Although there are several traditional methods to determine a patterning performance of PR, it becomes more challenging as scale tighten. To this end, we develop a new analysis method, named ‘W-curve’, defining EUV PR resolution using ADI SEM images, that visualizes micro-bridge and -break defect cliffs and local CD uniformity at the same time. Using W-curve method, 3 different PR performance at 36 nm-pitch line/space pattern was clearly distinguished. Also, the obtained result was well correlated with time-series trend data and electric test data. Therefore, we believe that W-curve method could provide a new insight for understanding EUV PR performance and improve patterning performance in a facile and versatile manner.
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