Pattern defects of nanoimprint in atmospheric conditions

A nanoimprint technology is a promising candidate to fabricate sub-50 nm patterns with high-throughput and low cost. Especially, the nanoimprint using photo solidification is suitable for precise patterning because of suppression of pattern placement errors due to thermal expansion and/or strain of mold and wafer generated by high pressure between them. However, when nanoimprint is carried out in air with rather low pressure, a small volume of air remained in concave mold pattern gives rise to pattern defects (called as bubble defects) in the replicated patterns. In this paper, we investigate characteristics of generation of bubble defects in atmospheric conditions' nanoimprint.