Interferometric measurement of thickness of silicon nitride layer in bi-morph silicon MEMS
Year: 2006
Authors: Ferraro P., Paturzo M., De Nicola S., Finizio A., Pierattini G., Coppola G., Iodice M., Striano V., Gagliardi M.
Autors Affiliation: CNR – Istituto Nazionale di Ottica Applicata, Via Campi Flegrei 34, 80078 Pozzuoli (NA), Italy;
CNR – Istituto di Cibernetica, Via Campi Flegrei 34, 80078 Pozzuoli (NA), Italy;
Istituto per la Microelettronica e i Microsistemi – CNR, Via P. Castellino 111, 80131 Napoli, Italy;
LENS – European Laboratory for NonLinear Spectroscopy,Via G. Sansone 1, 50019, Sesto Fiorentino (FI), Italy
Abstract: In this paper is reported a method for measuring the thickness of a silicone nitride layers employed for fabricating silicon MEMS bi-morph structures. The method allows the precise evaluation of layer thickness by adopting Digital Holographic Microscope. The measurement is based on the fact that the silicon nitride layer is transparent to the visible light. The optical phase difference (OPD) between the light beam traveling through the layer and portion of the beam in air is measured exploiting an interferometric technique. The approach is very simple and can be utilized even for inspection of non-planar or stressed structures. Experimental values have been compared with ellipsornetric measurements.
Journal/Review: PROCEEDINGS OF SPIE
Volume: 6188 Pages from: 61880R to: 61880R
More Information: This research was partially funded by the Ministero dellKeyWords: interferometry; MEMS; Digital Holography; thickness measurement; DOI: 10.1117/12.664096Connecting to view paper tab on IsiWeb: Click here