Abstract
The development of nanofacula array is an effective methods to improve the performance of Near-field Scanning Optical Microscopy (NSOM) and achieve high-throughput array scanning. The nanofacula array is realized by preparing metal nanopore array through the "two etching-one development" method of double-layer resists and the negative lift-off process after metal film coating. The shading property of metal film plays important rules in nanofacula array fabrication. We investigate the shading coefficient of three kinds of metal films (gold–palladium alloy (Au/Pd), platinum (Pt), chromium (Cr)) under different coating times, and 3.5 min Au/Pd film is determined as the candidate of the nanofacula array fabrication for its lower thickness (about 23 nm) and higher shading coefficient (≥ 90%). The nanofacula array is obtained by irradiating with white light (central wavelength of 500 nm) through the metal nanopore array (250/450 nm pore diameter, 2 μm pore spacing and 7 μm group spacing). Moreover, the finite difference and time domain (FDTD) simulation proves that the combination of nanopore array and microlens array achieves high-energy focused nanofacula array, which shows a 3.2 times enhancement of electric field. It provides a new idea for NSOM to realize fast super-resolution focusing facula array.
Highlights
The development of nanofacula array is an effective methods to improve the performance of Near-field Scanning Optical Microscopy (NSOM) and achieve high-throughput array scanning
Synge suggested that super-resolution imaging could be achieved by scanning and collecting the light signal of sample point by point with a detector of sub-wavelength size placed in the nearfield range of the sample, which is the origin of near-field scanning optical microscope (NSOM)[1]
We optimized the shading coefficient and coating time of different metal films, as well as the thickness of the polymethyl methacrylate (PMMA) according to the thickness of the metal film for development of a metal nanopore array applied to improve the performance of NSOM
Summary
The development of nanofacula array is an effective methods to improve the performance of Near-field Scanning Optical Microscopy (NSOM) and achieve high-throughput array scanning. The nanofacula array is realized by preparing metal nanopore array through the "two etching-one development" method of double-layer resists and the negative lift-off process after metal film coating. The finite difference and time domain (FDTD) simulation proves that the combination of nanopore array and microlens array achieves high-energy focused nanofacula array, which shows a 3.2 times enhancement of electric field It provides a new idea for NSOM to realize fast super-resolution focusing facula array. Substrate, positive resist is usually applied in EBL; whereas, it is necessary to fabricate sunken metal structure using PMMA-HSQ double-layer resist With this method, the Rommel’s group made a square metal block array of side-length 100 nm and a spacing less than 10 nm in a large range of 100 μm × 100 μm[12]. It provides a new way for NSOM to realize super-resolution focused facula array
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
