Options
2009
Journal Article
Titel
High speed and high precision Fs-laser writing using a scanner with large numerical aperture
Abstract
Currently available high speed scanning systems based on galvo mirrors are equipped with ob-jectives with small numerical apertures (NA < 0.2) which are not sufficient for most of the in-volume micro structuring processes. Whereas high precision air bearing translation stages are used with microscope objectives the speed is limited to approximately 100 mm/s. In order to overcome these limitations we integrated a galvo scanner into a system with large maximum scanning velocity (50 - 400 mm/s), large numerical aperture (NA = 0.4-1.2), small focus size (0.6 - 2.2 mm), high pre-cision (100 - 400 nm) and computer controlled pre-compensation of spherical aberrations for in-volume focusing. Furthermore, we combined the scanning system with a computer controlled three axis translation stage to process large flat work pieces such as wafers up to 2 mm in thickness. As application of the scanner high speed direct writing of waveguides, markings, nano structures inside transparent materials as well as the high speed fabrication of 3D micro structures by in-volume se-lective laser etching are demonstrated.