Authors: O. Tigli, M.E. Zaghloul
Affilation: Washington State University Vancouver, United States
Pages: 601 - 604
Keywords: MEMS, biosensor, FEM, CMOS, surface acoustic wave
Finite element (FE) modeling and performance analysis of Surface Acoustic Wave (SAW) devices that are developed in CMOS (Complementary Metal Oxide Semiconductor) technology are presented. CMOS-SAW devices were designed, fabricated and characterized as a biosensor for breast cancer biomarker detection . A detailed 3D model with 18 CMOS layers and a structured FE analyses methodology are laid out to extract the acoustic behavior of the substrate and the piezoelectric material of interest, zinc oxide (ZnO). The model represents 0.5 μm AMIS 3-metal, 2-poly process that was used to fabricate CMOS-SAW devices. A three-step analysis encompassing modal, harmonic and transient simulations is detailed. Experimental characterization results for the fabricated CMOS-SAW devices with operating frequency of 322.7 MHz show close agreement to the FE simulations with only 0.8 % deviations for operation frequency. Displacement, stress/strain maps for wave propagation, induced voltage distribution and phase responses are also presented. The results demonstrate that commercial FEM toolsets can provide valuable insight into understanding acoustoelectric interactions and wave characteristics or can readily be used for accurate design parameter extraction through reliable simulation of SAW device performance.