A novel positive tone development method for defect reduction in the semiconductor 193 nm immersion lithography process

Abstract

Patterning defects are considered primary killers for device yield and effective defect reduction is critical for semiconductor manufacturing. In the current work, a new positive tone development method is discussed to reduce defects for the 193 nm immersion lithography process. Photoresist develop processing is optimized via tuning of different process related parameters for complete coverage of the developer solution. Meanwhile, splash during development was minimized to achieve superior lithography performances and defect reduction. Lithographic depth of focus, critical dimension uniformity and line edge/width roughness were improved after 193 nm immersion exposure and etching for pattern transfer. Impact of the development method on defect reduction was also investigated. There was a 10x reduction in the bridging defect after patterning transfer for line/space patterning. The current work provides a strategy for positive tone development with significant defect reduction and improving our understanding of defect control from track related processing, which is of far-reaching significance for improvement in production yield for semiconductor manufacturing.