Nanometre accuracy and resolution metrology over large areas is becoming more and more a necessity for the progressof precision and especially for nano manufacturing. In recent years, the TU Ilmenau has succeeded in developing thescientific-technical basics of new ultra-high precision, so called nanopositioning and nanomeasuring machines. In furtherdevelopment of the first 25 mm machine, known as NMM-1 from SIOS Meßtechnik GmbH, we have developed andbuilt new machines having measuring ranges of 200 mm × 200 mm × 25 mm at a resolution of 20 pm and enablemeasuring reproducibility of up to 80 pm. This means a relative resolution of 10 decades. The enormous accuracy is onlymade possible by the consistent application of error-minimum measurement principles, highly accurate interferometricmeasurement technology in combination with highly developed measurement signal processing and comprehensive errorcorrection algorithms. The probing of the measurement objects can optionally be carried out with the aid of precisionoptical, interference-optical, tactile or atomic force sensors. A complex 3D measurement uncertainty model is used forerror analysis. The high performance could be demonstrated as an example in step height measurements with areproducibility of only 73 pm. The achieved resolution of 10~(-10) also presents new challenges for the frequency stabilityof the He-Ne lasers used. Here, the approach of direct coupling of the lasers to a phase-stabilized optical frequency combsynchronized with an atomic clock is pursued. The frequency stability is thus limited by the relative stability of the Rfreference to better than 4·10~(-12) (1s).
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