RT Conference Proceedings
SR 00
A1 Clement Lorenzo, Marta
A1 Olivares Roza, Jimena
A1 Iborra Grau, Enrique
A1 González Castilla, Sheila
A1 Sangrador García, Jesús
A1 Rimmer, Nick
A1 Rastogi, A.
A1 Ivira, B.
A1 Reinhardt, Alexandre
T1 Aluminium Nitride Solidly Mounted BAW Resonators with Iridium Electrodes
YR 2008
FD 22/04/2008-25/04/2008
AB In this work we investigated the performance of aluminium nitride (AlN)-based solidly mounted resonators (SMR) made with iridium (Ir) bottom electrodes. Ir/AlN/metal stacks were grown on top of insulating Bragg mirrors composed of alternate λ/4 layers of silicon oxi-carbide (SiOC) and silicon nitride (Si3N4).Ir electrodes of various thicknesses were electron-beam evaporated on different adhesion layers, which also acted as seed layers. AlN was deposited by sputtering after conditioning the Ir electrode by a soft-etch with Ar+ ions, which was essential to achieve high quality AlN films. The structure and morphology of the different layers were analysed by x-ray diffraction (XRD) and atomic force microscopy (AFM). The frequency response of the SMRs was assessed by measuring the input scattering parameterS11 with a network analyzer. The experimental results were fitted to the Butterworth-Van Dyke circuital model. The effective electromechanical coupling factor k2eff, and the quality factor Q of the resonators were derived from the experimental data. The influence of the thickness, crystal quality and roughness of the Ir bottom electrodes on the performance of the resonators was investigated.
T2 22nd European Frequency and Time Forum (EFTF) 2008
ED Toulouse, Francia
AV Published
LK http://oa.upm.es/3928/
UL http://www.eftf.org/proceedings/PDFs/FPE-0159.pdf