This paper presents a new method to manipulate microdevices’ membranes using nano-electrodeposits for directional microphones in hearing aid applications. The key to achieving high directionality is to minimize the mismatch of the omni-directional microphones using in-situ tuning by the integrated electrodeposition of metallic nanostructures. The nanostructures can be grown/retracted upon external bias at room temperature. The growth/retraction changes mass/stress distribution on the diaphragm of microdevices to precisely manipulate sensitivities to incoming acoustic waves. The omni-directional microphones are capacitive and have a parylene membrane integrated with the nanostructures. The microphone capacitance can be tuned up to 0.7 dB and acoustic mismatch reduces by 1.2 dB. This represents directivity index (DI) increase of 1.2 dB, which is crucial to achieve high directionality in composite microphones. The technology has many applications, including post-packaging trimming and calibration of micro-devices.

Original languageEnglish (US)
Title of host publication2008 Solid-State Sensors, Actuators, and Microsystems Workshop
EditorsKimberly L. Turner, Leland Spangler
PublisherTransducer Research Foundation
Number of pages4
ISBN (Electronic)0964002477, 9780964002470
StatePublished - 2008
Event2008 Solid-State Sensors, Actuators, and Microsystems Workshop - Hilton Head Island, United States
Duration: Jun 1 2008Jun 5 2008

Publication series

NameTechnical Digest - Solid-State Sensors, Actuators, and Microsystems Workshop


Conference2008 Solid-State Sensors, Actuators, and Microsystems Workshop
Country/TerritoryUnited States
CityHilton Head Island

ASJC Scopus subject areas

  • Control and Systems Engineering
  • Electrical and Electronic Engineering
  • Hardware and Architecture


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