MicroscannerCopyright: Fraunhofer ILT
Micro scanners are developed for productive structuring in the volume of transparent materials.
Currently available high speed scanning systems based on galvo mirrors are equipped with objectives with small numerical apertures (NA<0.2) 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 a galvo scanner we have build a microscanner with large maximum scanning velocity (50-400 mm/s), large numerical aperture (NA=0.4-1.2), small focus size (0.6-2.2 µm), high precision (100-400 nm) and computer controlled pre-compensation of spherical aberrations for in-volume focusing. Furthermore, the microscanner is combined with a computer controlled three axis translation stage to process large flat work pieces such as wafers up to 2 mm in thickness.
For high-power fs-laser radiation a high speed micro scanner is in development. A scanning velocity of >10m/s at a focus radius of 1 µm and a precision of 1µm are the goals to demonstrate the scalability of e.g. the ISLE process.