عنوان

Development of a Pull-In Free Electrostatic MEMS Microphone

شماره

TLpq2437830916

زبان متن نوشتاري يا گفتاري و مانند آن

انگلیسی

عنوان اصلي

Development of a Pull-In Free Electrostatic MEMS Microphone

نام عام مواد

[Thesis]

نام نخستين پديدآور

Ozdogan, Mehmet

نام ساير پديدآوران

Towfighian, Shahrzad

نام ناشر، پخش کننده و غيره

State University of New York at Binghamton

تاریخ نشرو بخش و غیره

2020

نام خاص و کميت اثر

135

جزئيات پايان نامه و نوع درجه آن

Ph.D.

کسي که مدرک را اعطا کرده

State University of New York at Binghamton

امتياز متن

2020

متن يادداشت

Today, sensors are everywhere with recent developments in technology, such as artificial intelligence and internet-of-things (IoT). Miniature microphones are one of the most commonly used sensors that have been integrated into billions of devices such as laptops, hearing aids, virtual reality headsets, smart speakers, and headphones. However, the sensitivity of the conventional electrostatic microphones has almost reached its theoretical limits. One approach for better-performing microphones is to increase the bias and reduce the noise, which eventually results in devices with a higher signal-to-noise ratio. However, with the current technology, one cannot increase the bias voltage at will due to the pull-in instability, which has a great potential to cause permanent damage to the released micro-structures. In this study, we propose an electrostatic micro-electro-mechanical-systems (MEMS) microphone with a radical change to the electrode configuration. This particular electrode scheme, which is called levitation based electrode design, enables capacitive MEMS sensors to work for large bias voltages without failing due to pull-in. The study presents the design, fabrication, and characterization of the microphone, which is made of approximately 2 μm thick highly-doped polysilicon diaphragm with a 1 mm2 surface area. The diaphragm is incorporated with finger-like electrodes on three sides of it. Right underneath these moving electrodes, there are 2 μm thick fixed electrodes with a 2 μm thick air gap. After the fabrication process, the mechanical and electrical responses of the microphones are measured in an acoustic chamber. The experimental results indicate that the microphone worked for a wide range of bias voltages (27-200 Volts) without any pull-in failure. They also reveal that the acoustic sensitivity increased up to a specific bias voltage, which suggests that there is an optimum bias to achieve the highest possible acoustic sensitivity. For some of the microphones, it was measured to be 16.1 mV/Pa at 200 V bias voltage, and the bandwidth was from 100 Hz to 4.9 kHz. Overall, the experimental results and simulations prove that integrating the levitation based electrode scheme to a MEMS sensor could yield high sensitivity devices that can handle high DC voltages, which is not feasible for most of the electrostatic microphones.

موضوع مستند نشده

Acoustics

موضوع مستند نشده

Engineering

موضوع مستند نشده

Mechanical engineering

مستند نام اشخاص تاييد نشده

Ozdogan, Mehmet

مستند نام اشخاص تاييد نشده

Towfighian, Shahrzad

نام الکترونيکي

فرمت انتشار

p

نوع ماده

[Thesis]

کد کاربرگه

276903

سطح دسترسي

a

تكميل شده

Y