Evaluating the effect of pressure on the diaphragm micro- electro-mechanical thickness and the amount of shift in medical applications

Subject Areas : Renewable energy

Nazli Zargarpour ¹

1 - Young Researchers and Elite Club, Ilkhchi Branch, Islamic Azad University, Ilkhchi, Iran.

Received: 2016-02-28 Accepted : 2017-03-12 Published : 2017-05-05

Keywords: displacement, Piezoelectric, COMSOL, Micro-Electro-Mechanical System, Diaphragm,

Abstract :

In this paper, the influence of design parameters on the sensitive microphone diaphragm for use in implantable medical applications is presented.The different parameters such as diaphragm shape, size, thickness and different applied pressures on the diaphragm has been considered. The effect of changes in these parameters on the displacement and stress in a variety of shapes of diaphragm is discussed. In order to design the optimal shape of the proposed diaphragm for the considered parameters, it has been simulated and analyzed in software COMSOL.According to the parameters, the diaphragm shapes of square, rectangular and oval with respect to the intended user, average central displacement in human hearing frequency range 20Hz-20KHz are nm 5. 5, nm2. 6, and nm 130 respectively .According to the results of the simulations, the oval-shaped diaphragm that has been studies in this paper, the possibility of implanted medical applications, performance is optimal than other shapes. In addition, the piezoelectric material is PZT which used in the design of the diaphragm.

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