A cleanroom-free approach towards a robust CMUT-based High Resolution 3D NDT system

虽然超声波是一种常见的无损检测(NDT)技术，但在性能和能力方面确实存在显著改进的需求。该项目旨在开发一种颠覆性和健壮的技术，以实现使用现有技术无法实现的高精度检查。产品的制造通常涉及金属或不同材料的连接。执行这项任务的一个常见过程是焊接，它通过将能量施加到感兴趣的区域来熔化和连接工件。激光焊接和电子束焊接两种焊接工艺被广泛应用于制造精密金属器件。一些例子包括电子包装、设备连接器和医疗组件。然而，温度变化引起的收缩和应力会在焊缝中产生裂纹。由于焊接接头较小，且通常不易接触，因此使用常规超声波探头进行检测非常困难。目前，这些焊接接头通常是通过对设备进行冶金切片来检验的，这是一种破坏性的解决方案。我们建议开发一种无洁净室的电容式微机械超声换能器(CMUT)，以便于在小型器件中实现激光焊接和电子束焊接的超声无损检测。CMUT具有高频、高带宽、高度小型化等特点，是一种理想的解决方案。无晶圆厂和坚固耐用的CMUT的可用性不仅将极大地提高检测性能；它还将是经济、耐用的，并允许巨大的设计灵活性和快速周转设计和制造时间。这项拟议的研究将推动加拿大走在无损检测技术的前沿，帮助加拿大的行业更具竞争力，降低成本，创造新的市场和创造就业机会。

Although ultrasound is a common Non-Destructive Testing (NDT) technology, there exists real demand for significant improvement in performance and capability. This project aims to develop a disruptive and robust technology to enable high accuracy inspections that are not achievable using current technologies. Manufacturing of products often involves jointing of metal or different materials. A common process to perform this task is welding, which melts and joins the workpieces by applying energy to the area of interest. Two types of welding process, namely laser welding and electron beam welding, have been widely used to produce delicate metallic devices. Some examples are electronic packaging, connectors for equipment, and medical components. However, shrinkage and stress due to temperature change can produce cracks in the weld. Because the weld joint is small and is usually not easily accessible, it is very difficult to use conventional ultrasonic probe to perform inspection. Currently, these weld joints are often examined by metallurgical sectioning of the device, which is a destructive solution. We propose to develop a cleanroom-free Capacitive Micromachined Ultrasound Transducers (CMUTs) to facilitate the ultrasonic NDT of laser welding and electron beam welding in small devices. The CMUT is the ideal solution because of its attributes such as high frequency, high bandwidth, and a high degree of miniaturization. The availability of fabless and robust CMUT will not only provide a huge improvement in detection performance; it will also be economical, robust and allow huge design flexibility and quick turnaround design and fabrication time. The proposed research will propel Canada to the fore-front of NDT technology, help Canadian industries to be more competitive, reduce cost, create new market and generate employment opportunities.