DEVELOPMENT OF HIGH FREQUENCY(>30 MHZ) ARRAY TRANSDUCERS

多层陶瓷加工将被研究作为一种方法，形成2- 2 PZT-聚合物复合材料的超声换能器的工作频率超过30 MHz。由压电PZT-聚合物复合材料制成的线性和相控阵列的制造目前被限制在小于10 MHz，这是由于需要加工成压电陶瓷的精细特征尺寸。切割锯技术目前仅限于15 μ m的切割宽度（切口）和> 20 μ m的柱宽度。然而，通过使用流延技术结合印刷的短效材料来形成切口，对于PZT射束宽度和30 MHz，尺寸&lt; 10 μ m< 5 um for kerf widths can be formed. This will allow the fabrication of linear and phased arrays with operating frequencies>，提供电子射束转向和动态聚焦，用于在诸如皮肤病学、眼科学和血管内成像的应用中的高分辨率成像。对于第一阶段的努力的可行性将证明通过制造一个单一的元素复合30兆赫换能器使用多层技术。在第二阶段，该技术将扩展到制造线性和相控阵列，并将在临床试验中进行测试。拟议的商业应用：高频相控阵超声换能器的潜在商业应用包括医学成像，其中感兴趣的特征尺寸非常小或需要高分辨率以获得准确度。 例如皮肤科（皮肤癌肿瘤成像）、眼科和微创手术的血管内成像。

Multilayer ceramic processing will be investigated as a method of forming 2- 2 PZT-polymer composites for ultrasound transducers with operating frequencies over 30 MHz. The fabrication of linear and phased arrays made from piezoelectric PZT-polymer composites is currently limited to less than 10 MHz by the fine feature sizes that need to be machined into piezoelectric ceramic. Dicing saw technology is currently limited to cut widths (kerf) of 15 um and post widths of > 20 um. However, by using tape casting technology in combination with a printed fugitive material to form kerfs, dimensions < 10 um for PZT beam widths and < 5 um for kerf widths can be formed. This will allow the fabrication of linear and phased arrays with operating frequencies> 30 MHz providing electronic beam steering and dynamic focus for high resolution imaging in applications such as dermatology, ophthalmology, and intravascular imaging. For the Phase I effort feasibility will be demonstrated by fabricating a single element composite 30 MHz transducer using multilayer technology. In Phase II the technique will be expanded to the fabrication of linear and phased arrays which will be tested in clinical trials. PROPOSED COMMERCIAL APPLICATIONS: Potential commercial applications of high frequency, phased array ultrasound transducers include medical imaging where feature sizes of interest are very small or where high resolution is needed for accuracy. Examples include dermatology (imaging of skin cancer tumors), ophthalmology, and intravascular imaging for minimally invasive surgery.