Regarding nano-sciences and nano-technologies there is a permanent confusion between resolution and accuracy. Many sophisticated devices (APM, AFM, SNOM, confocal microscopes) characterized by their resolution, are used to observe at the nano-scale but they are far from being metrological devices, i.e. they do not measure. A metrological instrument must be traceable to the internationally accepted unit: meter in our case. We present an optical setup able to measure in micrometer range with nanometer resolution and ten nanometers accuracy. Its utility for MEMS geometrical parameter is obvious. The setup is working on a passive vibration-isolated table and contains a SIOS laser interferometer which assures the traceability of the measurement, a high resolution translation table, and a long working distance microscope. Few hundred measurements were done to a linear grating to measure the micrometric range pitch with nanometer accuracy. A 2 10^-4 relative error was obtained.

Date Published: 7 January 2009
PDF: 4 pages
Proc. SPIE 7297, Advanced Topics in Optoelectronics, Microelectronics, and Nanotechnologies IV, 72971I (7 January 2009); doi: 10.1117/12.823665

Published in SPIE Proceedings Vol. 7297:
Advanced Topics in Optoelectronics, Microelectronics, and Nanotechnologies IV
Paul Schiopu; Cornel Panait; George Caruntu; Adrian Manea, Editor(s)