Measuring the Deformation of a Magnetically Levitated Plate
Deformations in lightweight moving structures such as the wafer stages in semiconductor lithography systems hinder the fabrication process with a high throughput rate. To compensate these deformations, accurate measurements are required. C. H. H. M. Custers and I. Proimadis at the Eindhoven University of Technology (NL) designed a prototype based on attocube’s interferometer IDS3010 to study these properties in more detail. A grid of 5 x 5 M12/F40 sensor heads detects the deformation of the mover inside a bearingless planar motor with nm accuracy. By accurately detecting the induced deformation, the goal of the experiment was the active attenuation of the deformation by properly shaping the force distribution on the magnetically levitated translator.
Characterizing a scanning fluorescence X-ray microscope
When developing an X-Ray microscope capable of nm resolution, careful design is a must. Thermal and mechanical stability of the components and assemblies has to be followed throughout the process. The FPS shows superior performance regarding its outstanding stability and its capability of measuring sub-nm displacements. The senor has a better than 1.25 nm stability over 40 hours, and a better then 300 pm resolution at 100 Hz bandwidth in a controlled environment. The FPS is therefore the ideal supplement for the mechanical control of all components used in the described X-Ray microscope setup achieving a resolution in the order of 40 nm, while the stability is below 45 nm over the entire time needed for data collection.
Measuring Water Surface Displacements
To measure the displacements of a cup’s water surface compared to the displacements of the table the cup is positioned on, two focused sensor heads were used: one of them focused on the water surface, the other focused on a mirror fixed to the table, while the table was hit by a hammer. The water surface oscillates with a maximum deflection of approximately ± 20 µm and the table oscillates with a maximum amplitude of around ± 0.7µm. The zoom highlights that the two measurement arms show similar behaviors in the high frequency range for the first milliseconds after the excitation.