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

虽然超声是一种常见的无损检测技术，但在性能和能力方面存在着巨大的改进需求。该项目旨在开发一种颠覆性和强大的技术，以实现使用当前技术无法实现的高精度检测。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，它通过向感兴趣的区域施加能量来熔化并连接工件。两种焊接工艺，即激光焊接和电子束焊接，已广泛用于生产精密金属器件。例如电子封装、设备连接器和医疗组件。然而，由于温度变化引起的收缩和应力会在焊缝中产生裂纹。由于焊缝接头很小，通常不容易接近，使用常规超声探头进行检测非常困难。目前，这些焊接接头通常通过设备的冶金切片进行检查，这是一种破坏性的解决方案。我们提出了一种无洁净室的电容式微机械超声换能器（CMUTs），以促进小型器件中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，是理想的解决方案。无晶圆厂和鲁棒CMUT的可用性不仅将大大提高检测性能；它也将是经济的，强大的，并允许巨大的设计灵活性和快速周转设计和制造时间。拟议的研究将推动加拿大走向无损检测技术的前沿，帮助加拿大工业更具竞争力，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.