Autofocusing on direct laser writing techniques in photoresist using photoluminescence analysis

Abstract

In the Direct Laser Writing (DLW) technique, autofocusing is necessary to determine the position of the laser focal spot precisely to ensure the success of the fabrication process. It can be used to determine the position of the laser focal spot on the glass substrate so that the fabricated structure can stick to the glass substrate and will not be lost during the development process. In the fabrication of layered structures, autofocusing is needed to determine the position of the laser focal spot on the surface of each layer, so that the structures can be formed properly. This study introduces a method for autofocusing in the DLW technique using photoluminescence (PL) analysis. By observing the PL intensity when the laser focal spot is moved across the photoresist, the position of the laser focal spot on the substrate or surface in the photoresist can be determined.