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Areal optical surface topography measurement is an emerging technology for industrial quality control. However, neither calibration procedures nor the utilization of material measures are standardized. State of the art is the calibration of a set of metrological characteristics with multiple calibration samples (material measures). Here, we propose a new calibration sample (artefact) capable of providing the entire set of relevant metrological characteristics within only one single sample. Our calibration artefact features multiple material measures and is manufactured with two-photon laser lithography (direct laser writing, DLW). This enables a holistic calibration of areal topography measuring instruments with only one series of measurements and without changing the sample.

The calibration of the height axis of optical topography measurement instruments is essential for reliable topography measurements. A state of the art technology for the calibration of the linearity and amplification of the z-axis is the use of step height artefacts. However, a proper calibration requires numerous step heights at different positions within the measurement range. The procedure is extensive and uses artificial surface structures that are not related to real measurement tasks. Concerning these limitations, approaches should to be developed that work for arbitrary topography measurement devices and require little effort. Hence, we propose calibration artefacts which are based on the 3D-Abbott-Curve and image desired surface characteristics. Further, real geometric structure s are used as an initial point of the calibration artefact. Based on these considerations, an algorithm is introduced which transforms an arbitrary measured surface into a measurement artefact for the z-axis linearity. The method works both for profiles and topographies. For considering effects of manufacturing, measuring, and evaluation an iterative approach is chosen. The mathematical impact of these processes can be calculated with morphological signal processing. The artefact is manufactured with 3D laser lithography and characterized with different optical measurement devices. An introduced calibration routine can calibrate the entire z-axis-range within one measurement and minimizes the required effort. With the results it is possible to locate potential linearity deviations an d to adjust the z-axis. Results of different optical measurement principles are compared in order to evaluate the capabilities of the new artefact

Controlling the point-spread-function in three-dimensional laser lithography is crucial for fabricating structures with highest definition and resolution. In contrast to microscopy, aberrations have to be physically corrected prior to writing, to create well defined doughnut modes, bottlebeams or multi foci modes. We report on a modified Gerchberg-Saxton algorithm for spatial-light-modulator based automated aberration compensation to optimize arbitrary laser-modes in a high numerical aperture system. Using circularly polarized light for the measurement and first-guess initial conditions for amplitude and phase of the pupil function our scalar approach outperforms recent algorithms with vectorial corrections. Besides laser lithography also applications like optical tweezers and microscopy might benefit from the method presented.

The standard ISO 25178-70 defines material measures for the calibration of 2D-and 3D-topography measurement devices. Some of the suggested material measures are established within the industrial application for a long time while others have not yet been extensively researched regarding their practical abilities. This paper describes a holistic and systematic investigation of the ISO 25178-70 material measures. The manufacturing of the suggested geometries is executed with twophoton laser lithography, alias direct laser writing (DLW). Since this manufacturing process is not yet frequently used in a material measures context, it is examined regarding its suitability for the fabrication of the ISO 25178-70 material measures. With DLW, it is possible to manufacture multiple material measures on one sample in order to enable a comprehensive calibration of optical topography measurement devices. The manufactured ISO 25178-70 geometries are examined using different 3D-topography measuring devices. In doing so, their abilities regarding the calibration of the devices can be evaluated and the practical feasibility of their industrial application is assessed. For the review of this practical usefulness, varying calibration and evaluation strategies are taken into account.