title: Dual-electrode CMUT with non-uniform membranes for high electromechanical coupling coefficient and high bandwidth operation.
abstract: In this paper, we report measurement results on dual-electrode CMUT demonstrating electromechanical coupling coefficient (k(2)) of 0.82 at 90% of collapse voltage as well as 136% 3 dB one-way fractional bandwidth at the transducer surface around the design frequency of 8 MHz. These results are within 5% of the predictions of the finite element simulations. The large bandwidth is achieved mainly by utilizing a non-uniform membrane, introducing center mass to the design, whereas the dual-electrode structure provides high coupling coefficient in a large dc bias range without collapsing the membrane. In addition, the non-uniform membrane structure improves the transmit sensitivity of the dual-electrode CMUT by about 2dB as compared with a dual electrode CMUT with uniform membrane.
authors: Rasim O
authors: RO
authors: Guldiken
authors: Jaime
authors: J
authors: Zahorian
authors: F Y
authors: FY
authors: Yamaner
authors: F Levent
authors: FL
authors: Degertekin
mesh_terms: D017076:Computer-Aided Design; D004566:Electrodes; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008567:Membranes, Artificial; D055617:Micro-Electrical-Mechanical Systems / Q000295:instrumentation*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014159:Transducers; D014463:Ultrasonography / Q000295:instrumentation*
chemical_list: D008567:Membranes, Artificial