Employment of fluorescence for autofocusing in direct laser writing micro-/nano-lithography

Abstract

Herein we present the implementation of autofocusing in multi-photon Direct Laser Writing (DLW) lithography. It is based on fluorescence occurring within the confined volume of a photopolymer/photoresin excitation resulting to a voxel generation. The proposed method is further successfully employed for the nanofabrication of large scale (500 nm in height, up to 25 mm 2 in area) Diffractive Optical Elements (DOE). The produced structures are characterized using Scanning Electron Microscope (SEM) and confocal optical profilometry. The introduced technique is potential for a simple, price and effort efficient upgrade of currently existing DLW micro-/nano-lithography setups.

3D Micro-Optics Via Ultrafast Laser Writing: Miniaturization, Integration, and Multifunctionalities

“…The technique has originated from nonlinear microscopy providing 3D-confined recording inside a ultraviolet (UV)-sensitive polymer [19,20]. Despite already appearing as commercially available setup still some active engineering is being carried out, for instance, implementation of active autofocusing and machine vision for sample detection and positioning [26,27]. Despite already appearing as commercially available setup still some active engineering is being carried out, for instance, implementation of active autofocusing and machine vision for sample detection and positioning [26,27].…”