Piezoelectric MEMS microphones for hearing aids

描述（由申请人提供）：大约有3000万美国人患有听力损失，他们将从某种形式的助听器中受益。然而，助听器（HA）的采用率很低，不到25% [Kochkin，（2009）]，而那些收养助听器的人要等10年以上才会这样做[Donahue，（2010）]。ha使用率低、迟迟不采用的原因有很多，包括有效性、价格、舒适度、尺寸和外观问题。显然，有必要改善HAs，以便那些患有听力障碍的人可以通过更好的治疗更有效地帮助他们提高生活质量和生产力。在本提案中，寻求开发一种用于HA应用的新麦克风，作为提高HA有效性和提高利用率的一种途径。特别是，将开发第一个满足助听器行业严格声学规格的压电，微机电系统（MEMS）麦克风。拨款的三个具体目标是：(1)设计和制造MEMS压电换能器元件，(2)设计和制造用于读出换能器电信号的放大电子元件，以及(3)为机械和电气元件设计符合HA应用要求的适当外壳。与已经主导该领域多年的现有驻极体电容麦克风（ECM）技术相比，新型麦克风将：对外部环境更坚固，随着时间的推移更稳定，易于助听器组装，并且以更小的尺寸提供卓越的声学性能。由于用于制造这种设备的MEMS制造是基于半导体工业中使用的相同工艺，因此一旦这些设备的设计完善，它们就可以以低成本制造，并且很容易与加工电子设备集成。我们的最终目标是开发一种比现有的麦克风提供更好的声学性能，而成本与手机麦克风相当的麦克风。鲁棒、稳定和微型麦克风的可用性将改善现有的高可用性系统，并促进利用多个麦克风进行方向传感和噪声消除的新高可用性系统的发展。NIH SBIR的目标是制造这些麦克风原型，这将作为助听器行业改进麦克风的基础。

DESCRIPTION (provided by applicant): Roughly 30 million Americans suffer from hearing loss and would benefit from some form of hearing augmentation. However, the hearing aid (HA) adoption rate is low, less than 25% [Kochkin, (2009)] and those who do adopt wait more than 10 years before doing so [Donahue, (2010)]. There are a variety of reasons for the low utilization rate and long delay in adopting HAs including effectiveness, price, comfort, size, and cosmetic issues. Clearly there is a need to improve HAs so that those who suffer from hearing impairment can be more effectively helped to improve their quality of life and productivity through better treatment. In this proposal, the development of a new microphone for HA applications is sought as one avenue to improve HA effectiveness and increase utilization. In particular, development of the first piezoelectric, micro-electromechanical system (MEMS) microphones that satisfy the stringent acoustical specifications of the hearing aid industry will be undertaken. The three specific aims of the grant are to (1) design and fabricate the MEMS piezoelectric transducer element, (2) design and fabricate the amplifying electronics for readout of the transducer's electrical signal, and (3) design an appropriate housing for the mechanical and electrical elements that meets the requirements for HA applications. Compared to the existing electret condenser microphone (ECM) based technology that has dominated the field for many years, the new microphone will: be more robust to the external environment, stable over time, ease hearing aid assembly, and deliver superior acoustic performance at a smaller size. Because the MEMS fabrication applied to create this device is based on the same processes used in the semiconductor industry, once the design of these devices is perfected they can be made at low cost and easily integrated with processing electronics. Our ultimate goal is to develop a microphone that provides better acoustic performance than present HAs at a cost comparable to microphones used for cell phones. The availability of robust, stable, and miniature microphones will improve existing and facilitate the development of new HA systems that utilize multiple microphones for directional sensing and noise cancellation. The goal of this NIH SBIR is to build these microphone prototypes, which will serve as the basis for improved microphones for the hearing aid industry.