title: 16 nm-resolution lithography using ultra-small-gap bowtie apertures.
abstract: Photolithography has long been a critical technology for nanoscale manufacturing, especially in the semiconductor industry. However, the diffractive nature of light has limited the continuous advance of optical lithography resolution. To overcome this obstacle, near-field scanning optical lithography (NSOL) is an alternative low-cost technique, whose resolution is determined by the near-field localization that can be achieved. Here, we apply the newly-developed backside milling method to fabricate bowtie apertures with a sub-15 nm gap, which can substantially improve the resolution of NSOL.  A highly confined electric near field is produced by localized surface plasmon excitation and nanofocusing of the closely-tapered gap. We show contact lithography results with a record 16 nm resolution (FWHM). This photolithography scheme promises potential applications in data storage, high-speed computation, energy harvesting, and other nanotechnology areas.
authors.affiliation: Micro and Nano Engineering Lab, University of Science and Technology of China, Hefei City, Anhui Province 230026, People's Republic of China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Chen
authors.forename: Jin
authors.initials: J
authors.lastname: Qin
authors.forename: Jianfeng
authors.initials: J
authors.lastname: Chen
authors.forename: Liang
authors.initials: L
authors.lastname: Zhang
authors.forename: Chengfu
authors.initials: C
authors.lastname: Ma
authors.forename: Jiaru
authors.initials: J
authors.lastname: Chu
authors.forename: Xianfan
authors.initials: X
authors.lastname: Xu
authors.forename: Liang
authors.initials: L
authors.lastname: Wang