Twymann Green interferometry in study of AlN material as an actuation layer in MEMS

C. Gorecki; K. Krupa; A. Andrei; M. Jozwik; L. Nieradko; P. Delobelle; L. Hirsinger

doi:10.1117/12.796072

Translator Disclaimer

11 August 2008 Twymann Green interferometry in study of AlN material as an actuation layer in MEMS

C. Gorecki, K. Krupa, A. Andrei, M. Jozwik, L. Nieradko, P. Delobelle, L. Hirsinger

Author Affiliations +

Proceedings Volume 7064, Interferometry XIV: Applications; 706402 (2008) https://doi.org/10.1117/12.796072
Event: Optical Engineering + Applications, 2008, San Diego, California, United States

Abstract

In this study we focus on the aluminium nitride (AlN). This material shows a large number of advantages associated with good piezoelectric properties. Therefore, AlN is an excellent candidate for MEMS actuation where low dielectric loss, low thermal drift and high signal-to-noise ratios are required. In this paper, the case of AlN driven cantilevers composed of three thin layers deposited on the silicon substrate will be considered. Precise knowledge of physical and material parameters of AlN applied in these simple elements are necessary for their further applications. However, up to now, AlN still represents a technological challenge and many of its micromechanical and piezoelectric properties are not precisely described. That is why, our study has been concentrated on determination of such parameters like the residual thin film stresses, thermal expansion coefficient α and piezoelectric coefficient d₃₁. In this paper the interactions between the theoretical solution, the numerical FEM simulations and experimental results were performed. This hybrid methodology allows to identify the main source of behaviors discrepancy between the physical and numerical model of tested cantilevers. Obtained knowledge leads to optimization of the technological process and required parameters of actuator functionality achievement by better understanding of the tested microdevices properties. In experimental procedure, it was used nanoindentation tests for obtaining an elastic properties of AlN, interferometric techniques for performing the static and dynamic measurements of cantilevers and scanning electron microscope for measuring topography.

Citation Download Citation

C. Gorecki, K. Krupa, A. Andrei, M. Jozwik, L. Nieradko, P. Delobelle, and L. Hirsinger "Twymann Green interferometry in study of AlN material as an actuation layer in MEMS", Proc. SPIE 7064, Interferometry XIV: Applications, 706402 (11 August 2008); https://doi.org/10.1117/12.796072

ACCESS THE FULL ARTICLE