Investigate a practical high sensitivity PVDF multielement SBCT ultrasound transd

描述（由申请人提供）：医疗超声换能器的世界市场每年超过10亿美元，每个换能器的平均成本超过5，000美元。换能器几乎完全由锆钛酸铅（PZT）制成，这种陶瓷具有限制图像轴向分辨率的不良窄带宽特性。在过去的十年里，电容式微机械超声换能器（CMUT）的挑战并没有对PZT在这个大市场中的排他性产生任何影响。 该应用是用聚偏二乙烯（PVDF）制造传感器，基于经过验证的模型和正式分析，发现多层低成本PVDF以独特的模式堆叠（开关巴克码传感器（SBCT））时，保留了材料的极宽带宽，并在创新的电子耦合方法中克服了PVDF的低介电特性。SBCT建模进一步预测了十一层SBCT的脉冲回波灵敏度等于或优于PZT。光刻生产的多元件换能器的层将由新开发的“纳米胶水”粘合，该胶水提供纳米层分离，并将促进通过市售拾取和放置设备每小时简单低成本组装数千个换能器。 通过所提出的方法制造的换能器可以在当今生产换能器的所有25种应用中取代PZT换能器，从OB/GYN到一次性心内换能器。该方法还在分辨率、灵敏度和成本方面得到改进。简单的光刻方法将定义传感器的尺寸、元件数量、形状和用途的特性。这将允许许多定制换能器以非常低的成本构建，频率从100 KHz到40 MHz。 由于更高的带宽，作为当今超声图像的特征的散斑将变得更加详细，但是同时频率复合也将变得更加有效，从而呈现具有整体更高分辨率和更深穿透的更清晰图像。弹性成像等模式将大大受益于这种带宽的改善，在诊断特异性。 本项目将构建一个13层15 MHz SBCT PVDF换能器，可与公司生产的15 MHz PZT换能器（60%带宽）进行比较，PZT换能器主要用于临床前弹性成像和光声，其中可以定量和单独评估传输和接收带宽。 该方法将允许以几十美元的成本来构造换能器，这大大降低了预计的医生成本，并且这，加上预计的分辨率增益，可以预期对医疗保健的质量和成本具有重大影响。 公共卫生相关性：在这个项目中，医疗超声换能器将由多层塑料（PVDF）使用巴克编码的安排，提供相当于当今最先进的陶瓷（PZT）换能器的灵敏度在不到1/10的成本，并提供极高的带宽为上级轴向分辨率，将找到应用在弹性成像和光声的新领域。该方法可以通过低成本光刻应用于所有应用的所有换能器，并且通过商业电子拾取和放置机器每小时可以容纳数千个生产。目前每年花费在医疗换能器上的10亿美元将大大减少，同时提供更清晰，更高分辨率的超声图像，具有更高的诊断用途。

DESCRIPTION (provided by applicant): The world market for medical ultrasound transducers exceeds one billion dollars annually, with an average cost to the physician exceeding $5,000 for each transducer. Transducers are made almost exclusively from lead zirconate titanate (PZT), a ceramic which has undesirable narrow bandwidth characteristics that limit the image's axial resolution. A challenge by Capacitive Micromachined Ultrasonic Transducers (CMUT) over the last ten years has not made any impact on PZT's exclusivity in this large market. This application, to make transducers from Polyvinylidene (PVDF), is grounded in a proven model and formal analysis which finds that multiple layers of low cost PVDF when stacked in a unique pattern (Switched Barker Code Transducer (SBCT)), preserves the material's extremely wide bandwidth and overcomes the PVDF's low dielectric characteristics in an innovative electronic coupling method. The SBCT modeling further predicts the pulse-echo sensitivity of an eleven layer SBCT to be equal or better than PZT. The lithographically produced multi-element transducer's layers will be bonded by newly developed "nanoglue" which provides a nanometer layer separation and will facilitate the simple low cost assembly of thousands of transducers per hour by commercially available pick and place equipment. Transducers manufactured by the proposed method can replace PZT transducers in all 25 of the applications where transducers are in production today, from OB/GYN to disposable intra cardiac transducers. This method also yields improvements in resolution, sensitivity, and cost. Simple lithographic methods will define the transducer's characteristics of size, number of elements, shape and use. This will allow many custom transducers to be constructed at very low cost for frequencies from 100 KHz through to 40 MHz. The speckle that is a characteristic of today's ultrasound images will become more detailed due to the much higher bandwidth, but simultaneous frequency compounding will also become much more effective rendering clearer images of overall higher resolution and deeper penetration. Modalities such as elastography will benefit greatly in diagnostic specificity from this bandwidth improvement. A thirteen layer 15 MHz SBCT PVDF transducer will be constructed in this project which can be compared with the company's production 15 MHz PZT transducer (60% bandwidth) that is primarily used in preclinical elastography and photoacoustics, where bandwidth of transmission and reception can be quantitatively and separately evaluated. This proposed method will allow transducers to be constructed for tens of dollars which greatly reduces the projected physician's cost, and this, plus the projected gains in resolution, can be expected to have a major effect on the quality and cost of health care. PUBLIC HEALTH RELEVANCE: In this project medical ultrasound transducers will be constructed by a multilayer plastic (PVDF) using Barker Coded arrangement that provides equivalent sensitivity to today's state of the art ceramic (PZT) transducers at less than 1/10 of the cost and provides extremely high bandwidth for superior axial resolution that wil find application in the new fields of elastography and photoacoustics. The method can be applied to all transducers of all applications by low cost lithography and production an be accommodated in thousands per hour by commercial electronic pick and place machines. The current $ 1 billion spent on medical transducers per year will be greatly reduced while providing clearer, higher resolution ultrasound images with higher diagnostic use.