Abstract    This paper proposes a Micro-electro-mechanical (MEMS) capacitive pressure sensor that relies on the movable electrode displaced like a flat plate equal to the maximum center deflection of diaphragm. The diaphragm, movable electrode and mechanical coupling are made of polysilicon, gold and Si3N4, respectively. The fixed electrode is gold and the substrate is Pyrex glass. This proposed method increased the effective surface of capacitor and the displacement of movable electrode. The size of this sensor is 250×250 µm2 and the thickness of diaphragm is 1µm with 1 µm air gap. According to the results the sensitivity of sensor is 58.5

Keywords    BioMEMS, capacitive pressure sensor, Small size, High sensitivity, Mechanical coupling.

چکیده    این مقاله حس­گر فشار خازنی MEMS را ارائه داده است. در این طراحی الکترود متحرک مانند یک صفحه ثابت حرکت می­کند که میزان جابه­جایی آن برابر با حداکثر جابه­جایی مرکزی دیافراگم است. جنس دیافراگم، الکترود متحرک و کوپلینگ مکانیکی به ترتیب پلی سیلیکون، طلا و Si3N4 است. همچنین، الکترود ثابت از طلا و زیر لایه از شیشه­ی پیرکس تشکیل شده است. روش پیشنهادی موجب افزایش سطح موثر صفحات خازن و افزایش جابه­جایی الکترود متحرک می­شود. اندازه­ی این حس­گر برابر است با 250×250 میکرومترمربع، ضخامت دیافراگم 1 میکرومتر و فاصله­ی هوایی 1 میکرومتر می­باشد. مطابق با نتایج حساسیت حس­گر 58.5 است.

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