A fast thermal-curing nanoimprint resist based on cationic polymerizable epoxysiloxane
1 Department of Materials Science and Engineering, College of Engineering and Applied Sciences, National Laboratory of Solid State Microstructures, Nanjing University, Nanjing, 210093, People's Republic of China
2 Hewlett-Packard Laboratories, 1501 Page Mill Road, Palo Alto, CA, 94304, USA
3 Department of Electrical and Computer Engineering, University of Massachusetts, Amherst, MA, 01003, USA
Nanoscale Research Letters 2012, 7:380 doi:10.1186/1556-276X-7-380Published: 9 July 2012
We synthesized a series of epoxysiloxane oligomers with controllable viscosity and polarity and developed upon them a thermal-curable nanoimprint resist that was cross-linked in air at 110°C within 30 s if preexposed to UV light. The oligomers were designed and synthesized via hydrosilylation of 4-vinyl-cyclohexane-1,2-epoxide with poly(methylhydrosiloxane) with tunable viscosity, polarity, and cross-linking density. The resist exhibits excellent chemical and physical properties such as insensitivity toward oxygen, strong mechanical strength, and high etching resistance. Using this resist, nanoscale patterns of different geometries with feature sizes as small as 30 nm were fabricated via a nanoimprint process based on UV-assisted thermal curing. The curing time for the resist was on the order of 10 s at a moderate temperature with the help of UV light preexposure. This fast thermal curing speed was attributed to the large number of active cations generated upon UV exposure that facilitated the thermal polymerization process.