Development and Application of Dielectric Heating-assisted Nanoimprint for Sensors

• Main Authors: Tsung-Yeh Wu, 吳宗曄
• Other Authors: 楊申語
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/e3fxu9

博士 === 國立臺灣大學 === 機械工程學研究所 === 105 === This study developed dielectric heating-assisted nanoimprint lithography (NIL) for fabrication of nanostructures for sensors. Two kinds of dielectric heating sensitivity polymer solution were spin-coated onto different substrates, namely, Polyethylene terephthalate glycol-modified (PETG) on polycarbonate (PC) substrate, and polyvinyl chloride (PVC) on cyclic olefin polymer (COP) and glass substrates. Using the nanoimprint process, taking advantage of rapid heating of dielectric materials, the nanostructure on the Ni-Co master mold can be replicated onto substrates in a few seconds. The nanostructure were then coated with metal thin film using DC sputtering system. The characteristics of surface plasmon resonance (SPR) and surface enhanced Raman scattering (SERS) for sensing were evaluated. For PETG spin-coated film, patterned nanostructures including nanowire, nanorod, and nanogrid arrays were successfully fabricated on PC substrate. For SPR sensing, the silver-capped nanowires achieved a full width at half maximum (FWHM) of 6.01 nm and wavelength sensitivity of 550 nm / RIU. The functionality of the sensor was verified by the specificity of label-free antigen–antibody interactions with BSA and Anti-BSA, the minimum detection biomolecules of Anti-BSA reached 0.795 nM under 0.02 nm wavelength resolution. For PVC spin-coated film, the imprinted nanowire and nanorod nanostructures on COP and glass substrates were successfully made. The functionality of the label-free antigen–antibody interactions for BSA and Anti-BSA were used to verify the sensing ability under SPR measurement. In addition, taking advantage of the flexibility of PVC, ultraflexible film sensor was developed. Using the silver-capped nanowires in the bending condition to measure SPR, the angular sensitivity was 0.12 degree/nm and the minimum detection angle was 2.4x10-3 degree under 0.02 nm wavelength resolution. In SERS sensing, the curved gold-capped nanorods immobilized by 4-mercaptobenzoic acid (pMBA) can increase the density of Raman hot spot. Under curved radius of 6 mm, enhanced SERS signal was two times of that detected using a planar SERS substrate. This study confirmed the feasibility and potential of biosensors and ultraflexible film sensors fabricated using dielectric heating-assisted nanoimprint.