Abstract: A transducer device and method include affixing a preamplifier or other suitable circuit to a thin piezoelectric membrane. The membrane fully supports the circuit at an inactive region of the membrane. The membrane has at least one piezoelectrically active region that is connected to the circuit by a signal line. Preferably, the signal line is fabricated onto the membrane using integrated circuit fabrication techniques. In the preferred embodiment, the piezoelectrically active region has a diameter of less than one hundred microns and the membrane has a thickness of less than ten microns. A potting compound provides structural support of the membrane and insulates the on-membrane circuit.

Abstract: A method of patterning interconnect lines on a flexible membrane film of piezoelectric material includes securing the membrane film to a temporary support structure to allow direct patterning of the interconnect lines. A barrier plane is deposited onto the membrane film. A photoresist then coats the barrier plane. In a subsequent step of photolithographically exposing the photoresist, the barrier plane acts as a screen to prevent radiation from reaching the membrane film. The barrier film is also used as a focusing and alignment structure during photolithographic exposure. Optionally, the resulting structure is soaked in chlorobenzene, with the barrier plane functioning to prevent diffusion of the chlorobenzene through the back side of the porous membrane film to form undesired development-retarding regions of the photoresist. Openings are formed in the photoresist during a development step. A metallic interconnect layer is then deposited.

Abstract: A method of fabricating a membrane acoustic device includes utilizing integrated circuit fabrication techniques to form a support structure for a piezoelectric membrane, to pattern interconnect schemes on the membrane and on a semiconductor substrate, and to form electronic components for amplifying and driving signals generated at one or more piezoelectrically strong active areas. The support structure is a lithographically patterned metal layer on the semiconductor substrate. A matching metallization on the piezoelectric membrane is conductively bonded to the metal support structure of the semiconductor substrate. An acoustic cavity area is etched through the semiconductor substrate to the back surface of the membrane. An extremely small membrane hydrophone can thereby be fabricated for operation at frequencies above 50 MHz.

Abstract: Apparatus and method for representing slow motion of an oscillating heart by forming strobed images of the heart at a sequence of uniformly spaced times with controllable time interval lengths that are related to, but not identical to, the primary oscillation period T of the heart. The heart images may be formed at a sequence of times t=t.sub.0 +kMT.sub.h /N where t.sub.0 is an initial time, N is a positive integer, k=1,2, . . . , N-1 and M is a positive integer. Alternatively, the heart images may be formed at a sequence of times determined in part by the current oscillation cycle of the heart.