Show simple item record

dc.contributor.advisorHall, Neal A.en
dc.creatorKirk, Karen Deniseen
dc.date.accessioned2012-08-16T14:58:04Zen
dc.date.available2012-08-16T14:58:04Zen
dc.date.issued2012-05en
dc.date.submittedMay 2012en
dc.identifier.urihttp://hdl.handle.net/2152/ETD-UT-2012-05-5321en
dc.descriptiontexten
dc.description.abstractDirectional microphones, which suppress noise coming from unwanted directions while preserving sound signals arriving from a desired direction, are essential to hearing aid technology. The device presented in this paper abandons the principles of standard pressure sensor microphones, dual port microphones, and multi-chip array systems and instead employs a new method of operation. The proposed device uses a lightweight silicon micromachined structure that becomes “entrained” in the oscillatory motion of air vibrations, and thus maintains the vector component of the air velocity. The mechanical structures are made as compliant as possible so that the motion of the diaphragm directly replicates the motion of the sound wave as it travels through air. The microphone discussed in this paper achieves the bi-directionality seen in a ribbon microphone but is built using standard semiconductor fabrication techniques and utilizes piezoelectric readout of a circular diaphragm suspended on compliant silicon springs. Finite element analysis and lumped element modeling have been performed to aid in structural design and device verification. The proposed microphone was successfully fabricated in a cleanroom facility at The University of Texas at Austin. Testing procedures verified that the resonant frequency of the microphone, as expected, was much lower than in traditional microphones. This report discusses the theory, modeling, fabrication and testing of the microphone.en
dc.format.mimetypeapplication/pdfen
dc.language.isoengen
dc.subjectMicromachineden
dc.subjectMEMSen
dc.subjectMicrophoneen
dc.subjectPiezoelectricen
dc.subjectSensorsen
dc.subjectFabricationen
dc.subjectSiliconen
dc.titleDesign, fabrication, and testing of a MEMS z-axis Directional Piezoelectric Microphoneen
dc.date.updated2012-08-16T14:58:15Zen
dc.identifier.slug2152/ETD-UT-2012-05-5321en
dc.contributor.committeeMemberNeikirk, Dean P.en
dc.description.departmentMechanical Engineeringen
dc.type.genrethesisen
thesis.degree.departmentMechanical Engineeringen
thesis.degree.disciplineMechanical Engineeringen
thesis.degree.grantorUniversity of Texas at Austinen
thesis.degree.levelMastersen
thesis.degree.nameMaster of Science in Engineeringen


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record