Abstract    In this paper we present a new model for calculating the capacitance of MEMS sensor with corrugated diaphragm. In this work the effect of residual stress is considered on deflection of diaphragm and capacitance of sensor. First, a new analytical analyzes have been carried out to derive mathematic expressions for central deflection of corrugated diaphragm and its relationship with residual stress. Then the capacitance and sensitivity of sensor using corrugated diaphragm with residual stress are calculated under various parameters such as bias voltage and pressure. The analytical results are compared with simulation using Finite Element Method (FEM). The results show that the new analytical model is very close with simulation results.

Keywords    residual stress, capacitance, corrugated diaphragm, sensor sensitivity

چکیده    در این مقاله روش جدیدی برای محاسبه ظرفیت خازنی سنسور میکروالکترومکانیکی با دیافراگم موج دار ارائه می­شود. همچنین اثر تنش پسماند بر روی جابجایی دیافراگم و ظرفیت خازنی سنسور در نظر گرفته می­شود. در ابتدا آنالیز تحلیلی برای بدست آوردن مقدار جابجایی مرکزی دیافراگم موج دار و رابطه­ی آن با تنش پس ماند صورت می­گیرد. سپس مقدار ظرفیت خازنی و حساسیت سنسور با دیافراگم موج دار دارای تنش پسماند تحت ولتاژ بایاس و فشار بدست آورده می­شود. نتایج تحلیلی با شبیه سازی که با استفاده از روش اجزاء محدود انجام شده است، مقایسه می­شود. مقایسه نشان می­دهد روش تحلیلی جدید به خوبی توانسته است نتایج شبیه سازی را دنبال کند.

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