Design and Development of 1-D CMUT Array with Diamond Membrane

Karacaer, Berkay
This thesis presents a new microfabrication method of 1-D capacitive micromachined ultrasonic transducer (CMUT) array featuring diamond membrane. This microfabrication method for diamond membrane CMUT array is based on the sacrificial etching of polysilicon in XeF2 plasma. The stiction problem of membranes due to capillary force in wet etching processes is avoided since the XeF2 is a gaseous chemical in plasma form that etches silicon and its derivatives with very high selectivity over silicon dioxide and diamond. The developed microfabrication process flow, the realization of the microfabrication process flow in the computer environment, and the design of the 64-element 1-D diamond membrane CMUT array are explained and demonstrated. In this thesis, in addition to the proposed microfabrication, a CMUT array structure named Faraday caged CMUT and a transmit and receive operation are proposed for electrical crosstalk and parasitic capacitance reduction. The finite element method (FEM) modeling of the regular 2-element 1-D CMUT array and the 2-element 1-D Faraday caged CMUT array are performed. The electrical properties and the electrical crosstalk of these CMUT arrays are examined and compared through computational analysis.


Development and microfabrication of capacitive micromachinedultrasound transducers with diamond membranes
Cezar, Mehmet; Bayram, Barış; Department of Electrical and Electronics Engineering (2011)
This thesis presents the development and microfabrication of capacitive micromachined ultrasonic transducers (CMUT) with diamond membranes for the first time in the literature. Although silicon and silicon nitride (Si3N4) membranes have been generally used as the membrane material in CMUTs. These membrane materials have moderate properties that can cause damage during the operation of CMUTs. In this thesis, a new material for the membrane is introduced for CMUTs. Diamond has exceptional potential in the are...
Design and Optimization of an Electromagnetic Micro Energy Scavenger with Parylene Cantilevers
Sarı, İbrahim; Balkan, Raif Tuna; Külah, Haluk (2007-11-29)
This paper presents the design, optimization, and implementation of an electromagnetic micro energy scavenger that uses an array of parylene cantilevers on which planar coils are fabricated. The coils are connected electrically in series to increase the voltage that is generated by virtue of the relative motion between the coils and the magnet. A detailed mathematical modeling and optimization of the design for various cases are carried out.
Design of a microbial sensor using conducting polymer of 4-(2,5-di(thiophen-2-yl)-1H-pyrrole-1-l) benzenamine
Tuncagil, Sevinc; ODACI DEMİRKOL, DİLEK; Yidiz, Ersin; TİMUR, SUNA; Toppare, Levent Kamil (Elsevier BV, 2009-03-28)
A microbial biosensor based on Gluconobacter oxydans cells immobilized on the conducting polymer of 4-(2,5-di(thiophen-2-yl)-1H-pyrrol-1-yl)benzenamine (SNS-NH2) coated onto the Surface of graphite electrode was constructed. The proposed biosensor was characterized using glucose as the Substrate. The linear relation was observed in the range of 0.1-2.5 mM and defined by the equation y = 0.415x + 0.377 (R-2 = 0.986). Analytical characterization, effects of electropolymerization time, pH, cell amount and the ...
Bayram, Barış; Kupnik, Mario; Khuri-Yakub, Butrus T. (2006-01-01)
This paper reports on the finite element analysis (FEA) of crosstalk in capacitive micromachined ultrasonic transducer (CMUT) arrays. Finite element calculations using a commercial package (LS-DYNA) were performed for an immersed I-D CMUT array operating in the conventional and collapsed modes. LS-DYNA was used to model the crosstalk in CMUT arrays under specific voltage bias and excitation conditions, and such a modeling is well worth the effort for special-purpose CMUT arrays for ultrasound applications s...
Experimental characterization of collapse-mode CMUT operation
Oralkan, Omer; Bayram, Barış; Yaralioglu, Goksen G.; Ergun, A. Sanli; Kupnik, Mario; Yeh, David T.; Wygant, Ira O.; Khuri-Yakub, Butrus T. (2006-08-01)
This paper reports on the experimental characterization of collapse-mode operation of capacitive micromachined ultrasonic transducers (CMUTs). CMUTs are conventionally operated by applying a direct current (DC) bias voltage less than the collapse voltage of the membrane, so that the membrane is deflected toward the bottom electrode. In the conventional regime, there is no contact between the membrane and the substrate; the maximum alternating current (AC) displacement occurs at the center of the membrane. I...
Citation Formats
B. Karacaer, “Design and Development of 1-D CMUT Array with Diamond Membrane,” M.S. - Master of Science, Middle East Technical University, 2022.