A first operational nanometric transfer standard
For several years now, the Optics Metrology Laboratory in Optics Group at SOLEIL (LMO) has benefited from LNE (Laboratoire National de metrologie et d'Essais)'s expertise in dimensional metrology by Atomic Force Microscopy (AFM) for the characterisation of the diffractive optics used in SOLEIL's beamlines. This ongoing interaction has helped LMO to control its measurement uncertainties, and in return the LNE has benefited from LMO's measurement resources and the Dimensional Metrology Laboratory (MetroDim) at SOLEIL for the development of a metrological AFM.
The signing of a partnership agreement in December 2018 therefore consolidated an already very active interaction situation and formalises the beginning of new joint projects, targeting the development of new calibration methods for AFM and in particular the development of standards based on innovative principles : A virtual step standard. It would be carried out by means of an Interferometer controlled translation plate, which would generate traceable displacements directly under the tip of the AFM. This would provide a single standard for coverage of the entire measurement range of the instrument, thereby improving its accuracy.
Under this agreement, the SOLEIL teams will have access to the metrological characterisation of the nanomaterials platform at LNE (Carmen platform based in Saint Quentin en Yvelines). In return, the LNE will have access to the LMO and MétroDim measuring equipment at SOLEIL.
The LMO has undertaken to apply for accreditation of part of its metrology activities according to the ISO 17025 standard "General requirements for the competence of testing and calibration laboratories". This requires that its instruments be directly linked to the International System of Units. The new collaboration framework will facilitate cross calibrations.
An essential step in this process was taken on April 1, 2019, with the presentation by LNE to SOLEIL of a first standard with its calibration certificate (see picture below).
Figure 1: The first standard, with its calibration certificate, is delivered by LNE to the LMO. From left to right: M. Ramaz (LNE) F. Polack and M. Thomasset (SOLEIL- LMO), S. Ducourtieux and A. Delvallée (LNE)