A design and a manufacturing method of
ultrasound transducers based on films of ferro-electric
ceramic material is presented, the transducers being particularly useful for operating at frequencies above 10 MHz. The designs also involve acoustic load matching
layers that provides particularly wide bandwidth of the transducers, and also multiple electric port transducers using multiple piezoelectric
layers, for multi-band operation of the transducers over an even wider band of frequencies that covers ~4
harmonics of a fundamental band. A
transceiver drive
system for the multi-port transducers that provides simple selection of the frequency bands of transmitted pulses as well as transmission of multi-band pulses, and reception of scattered signals in
multiple frequency bands, is presented. The basic designs can be used for elements in a
transducer array, that provides all the features of the
single element transducer for array steering of the focus and possibly also direction of a
pulsed ultrasound beam at high frequencies and multi-band frequencies. The manufacturing technique can involve tape-
casting of the
ceramic films, deposition of the
ceramic films onto a substrate with thick film printing,
sol-gel, or other deposition techniques, where manufacturing methods for load matching
layers and
composite ceramic layers are described.