Development of laser positioning system of high accuracy in the nanometer range

Direct Laser Writing techniques like two-photon-polymerization or UV-lithography have become common tools for the micro- and nanofabrication of precise devices like photonic crystals. A decrease in the size of structures of special devices requires a significant better resolution of the laser beam system that can be determined by using different photoinitiators or a second depletion laser for STED-lithography. However, besides the optical limits for the resolution of the laser system due to diffraction effects, the positioning systems for the laser beam or the sample stage lead to further imprecisenesses. To benefit from the high resolution techniques for the structuring process, the need for highly accurate positioning systems has dramatically grown during the last years. A combination of lithographic techniques with a nanopositioning and nanomeasuring machine NMM-1, developed at the TU Ilmenau, enables high precision structuring capability in an extended range. The large positioning volume of 25mm x 25mm x 5mm with a resolution in the sub-nanometer range is a good condition for ultra precision manufacturing with large area 3D-Laser-Lithography. Advantages and disadvantages as well as further developments of the NMM-1 system will be discussed related to current developments in the laser beam and nanopositioning system optimization. Part of the further development is an analysis of the implementability of additional ultra precise rotational systems in the NMM-1 for the unlimited addressability perpendicular to the surface of a hemisphere as key strategy for multiaxial nanopositioning and nanofabrication systems.