Ultrasonography is a well-established technology. Common areas of application include material characterization and testing as well as medical diagnostics. Currently, ultrasonic transducers are manufactured based mainly on a piezoelectric material or piezo composite. These transducers possess properties adequate for applications across spaces of open air (distance measurement) or in the field of high-frequency material testing. However, they fall short particularly with high-resolution imaging, invasive testing and material testing of liquids.
Ultrasonic transducers manufactured with micromachining technology (MUT) can overcome these drawbacks. MUTs are basically MEMS structures which consist of two electrodes. One of the electrodes is fixed, the other is movable. An insulating layer and a vacuum-sealed gap separate the electrodes. The movable electrode in piezoelectric ultrasonic transducers (PMUT) are stimulated by a piezoelectrical film, e.g. AIN. In capacitive micromachined ultrasonic transducers (CMUT), stimulation occurs through electrostatic deflection of the movable electrode.
Fraunhofer IPMS offers research as well as development and pilot production of micromachined components for innovative areas of application.