The Nanostage3D translation stage is developed within the Control Systems Technology group at the Technische Universiteit Eindhoven. It is an elastically guided, low hysteresis stage with a measurement volume of 1x1x1 mm and integrated interferometric displacement sensors. The stage measures ø250x190mm.

The translation stage forms part of a metrological atomic force microscope (AFM) designed for the Dutch Metrology Institute VSL. The stage moves the sample, the AFM remains stationary to fulfil the Abbe principle. Since the AFM is kinematically connected to the stage it can easily be replaced with any other appropriate measurement probe.

Three identical axes which are aligned symmetrically around the vertical make up the Nanostage3D. This parallel setup results in improved dynamical behaviour over stacked designs and better environmental disturbance attenuation. Furthermore, the higher allowable scanning speed reduces measurement time and subsequently minimizes the influence of temperature variations on the measurement results.

Custom, differential interferometers (DPMI's) measure the translations of the stage. The optical axes of these orthogonally orientated interferometers are aligned with the measurement probe for minimal Abbe offset. The 3D position resolution is 0.3 nm, the specified combined measurement uncertainty is in the nanometre range.

The stage contains the measurement mirror while the reference mirror is kinematically connected directly to the AFM or similar probe, resulting in a favourably short measurement loop. The thermal centre of expansion of the mirrors coincides with the measurement probe for optimal thermal stability.

Lorentz-type motors are used for the actuation of the stage. To minimize the heat generated by these actuators, weight and stiffness compensation mechanisms are included.

The project is supported by Nanoned.

Technische Universiteit Eindhoven VSL - Dutch Metrology Institute NanoNed