Large contrast enhancement by sonication assisted cold development process for low dose and ultrahigh resolution patterning on ZEP520A positive tone resist

• Main Authors: Tobing, Landobasa Yosef Mario A. L., Tjahjana, Liliana, Zhang, Dao Hua
• Other Authors: School of Electrical and Electronic Engineering
• Format: Article
• Language: English
• Published: 2013
• Subjects: DRNTU::Engineering::Electrical and electronic engineering::Microelectronics
• Online Access: https://hdl.handle.net/10356/99454; http://hdl.handle.net/10220/17831
• Institution: Nanyang Technological University

The authors demonstrate a robust, low dose, high contrast, and ultrahigh resolution patterning process based on sonication assisted development of ZEP520A positive tone resist in both room and cold temperature. The contrast as high as γ ∼ 25 and γ ∼ 9.14 can readily be achieved in 6 °C and room temperature development, respectively, in diluted n-amyl acetate solution. The high contrast is demonstrated on 90 nm thick ZEP resist at 20 kV acceleration voltage, from which 20 nm thick titanium lift-off of 60 nm pitch lines and 50 nm pitch dots can be successfully achieved.