Project: AkteMUS - Development of a highly efficient method for active acoustic testing of miniaturized ultrasonic structures in substrate and carrier composites

Ultrasonic sensors are used in a variety of applications today, from diagnostics to 3D imaging in medical technology and industrial measurement technology. Miniaturized ultrasonic transducers based on MEMS structures, such as the capacitive micromachined ultrasonic transducers (CMUT) from Fraunhofer IPMS, enable an innovative leap to new applications (e.g. more reliable detection of middle ear infections and reactive gripping in robotics) due to their reduced sensor size. The use of these silicon-based capacitive ultrasonic transducers opens up the potential to manufacture ultrasonic sensors in high volumes at very low cost.

For quality assurance purposes, ultrasonic sensors must be carefully tested for functionality before they are used. The currently applied electrical test is the main cost driver during the whole manufacturing process due to the time required, causing up to half of the manufacturing costs.

The aim of the project is to develop a new acoustic test method to test miniaturized ultrasonic elements for their properties and functional parameters after they have been separated from the silicon substrate composite. The innovative acoustic functional testing as well as the measurements on miniaturized and diced devices ("frame probing") will result in new powerful and flexible test systems. The test procedure researched in the AkteMUS project comes very close to the operating conditions of a device and reduces the measurement time of devices with a high number of channels. The research and development project addresses active test procedures, which can also be used for other MEMS devices and active principles in the future. In addition, the influence of handling, packaging and environmental influences will be evaluated in close cooperation with the joint venture partner aSpect Systems GmbH. This opens up new possibilities and markets for the testing of MEMS devices in addition to the currently established test scenarios. The continuous further development of MEMS sensors and actuators at Fraunhofer IPMS thus benefits in the long term in a very broad overall context from the provision of efficient test procedures for miniaturized components in substrate composites by the AkteMUS project.