Fabrication of nano-sized resist patterns on flexible plastic film using thermal curing nano-imprint lithography

• Published in: Microelectronic engineering Vol. 83; no. 2; pp. 323 - 327
• Main Authors: Lee, Heon, Hong, Sunghoon, Yang, Kiyeon, Choi, Kyungwoo
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.02.2006; Elsevier Science
• Subjects: Applied sciences; Benzyl-methacrylate monomer; Electronics; Exact sciences and technology; Flexible substrate; Hot embossing nano-imprinting lithography; Microelectronic fabrication (materials and surfaces technology); Monomer based imprinting lithography; PET (polyethylene-terephthalate) film; Polymerization; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Thermal initiator; Transparent polymer film; Flexible substrate; Hot embossing nano-imprinting lithography; Monomer based imprinting lithography; PET (polyethylene-terephthalate) film; Transparent polymer film; Benzyl-methacrylate monomer; Polymerization; Thermal initiator; Polyethylene; Patterning; Heat treatment; Polymer films; Experimental study; Nanolithography; Plastic film; Terephthalate polymer; Transparent thin film; Microelectronic fabrication; Experimental result; Curing(plastics); Flexible structure; Resist
• ISSN: 0167-9317; 1873-5568
• DOI: 10.1016/j.mee.2005.09.006

Due to polymer’s excellent flexibility, transparency, reliability and light weight, it is a good candidate material for substrate of devices including organic electronic devices, biomedical devices, and flexible displays (LCD and OLED). In order to build such devices on polymer, nano- to micron-sized patterning must be accomplished. Since polymer materials reacts with organic solvents or developer solutions which are inevitably used in photolithography and cannot bear high temperature (∼140 °C) process for photoresist baking, conventional photolithography cannot be used to polymer substrate. In this research, monomer based thermal curing imprinting lithography was used to make as small as 100 nm dense line and space patterns on flexible PET (polyethylene-terephthalate) film. Compared to hot embossing lithography, monomer based thermal curing imprint lithography uses monomer based imprint resin which consists of base monomer and thermal initiator. Since it is liquid phase at room temperature and polymerization can be initiated at 85 °C, which is much lower than glass temperature of polymer resin, the pattern transfer can be done at much lower temperature and pressure. Hence, patterns as small as 100 nm were successfully fabricated on flexible PET film substrate by monomer based thermal curing imprinting lithography at 85 °C and 5 atm without any noticeable degradation of PET substrate.