Holograms recording with pulsed laser on diazonaphthoquinone-novolac-based photoresists and their nanocomposites

Abstract

Direct write digital holography technique (DWDH) using a single 440-nm pulsed laser exposure has been proposed to record master holograms on commercially available positive-tone photoresist systems based on a mixture of diazonaphthoquinone and novolac resin (DNQ-novolac) of different thicknesses. The DNQ-novolac nanocomposite doped with copper nanoparticles (CuNPs) films was also used. The method for numerical evaluation of hologram quality based on reflected beam diffraction intensity measurements was proposed and verified. It was found that all investigated photoresist nanocomposites were sensitive enough to record holographic structures at low single pulse laser exposures (from 3.3 to 18.0 mJ∕cm 2 ). Moreover, doping DNQ-novolac nanocomposite with CuNPs s increases its sensitivity to pulsed laser exposure by more than 30%. The potential of single pulsed laser exposures to record high quality master holograms on commercially available and metal nanoparticles doped photoresists with at least five times lower exposures values as compared to the continuous-wave laser exposures usually used to expose photoresist materials in holographic applications, opens the possibility to use pulsed lasers for quick master-originals origination for embossed holograms applying a DWDH technique or analog methods.

Printable Nanophotonic Devices via Holographic Laser Ablation

“…12 Practical approaches can be realized by recording images in photoresist, which can be transformed into a nickel surface relief grating for embossing holograms in hydrophobic polymers. 13 The use of photoresist requires high-cost and customized equipment for fabricating the master holograms. Surface gratings can also be written by complex techniques such as E-beam lithography (EBL) and focused ion beam (FIB) milling.…”

“…While photopolymers are recorded in the same mode, they can be cured by heat treatment or ultraviolet/visible light exposure . Practical approaches can be realized by recording images in photoresist, which can be transformed into a nickel surface relief grating for embossing holograms in hydrophobic polymers . The use of photoresist requires high-cost and customized equipment for fabricating the master holograms.…”