Abstract: The invention relates to an ultrasonic transducer comprising a plurality of micro-cells, arranged in an array having M rows and N columns, and driving electronic means apt to connect in parallel to each other said micro-cells so as to form at least two sub-groups of said micro-cells, the micro-cells of each sub-group being connected in parallel to each other, at least one column of said array comprising micro-cells belonging to at least two different adjacent sub-groups, so that a radiation emitted in a direction perpendicular to the array columns by said at least one column has a phase that is intermediate between the phases of said at least two different adjacent sub-groups.

Abstract: The invention relates to a microfabricated capacitive ultrasonic transducer (20) comprising at least one thin plate (21), provided with a metallization (24), suspended over a conductive substrate (23) through supporting elements integrally coupled to the conductive substrate (23), the conductive substrate (23) forming one or more electrodes corresponding to said at least one thin plate (21), characterized in that said supporting elements comprise an ordered arrangement of columns or “pillars” (22) to which the thin plate (21) is integrally coupled, whereby the pillars (22) operate as substantially punctiform constraints. The invention further relates to a surface micro-mechanical process for fabricating such microfabricated capacitive ultrasonic transducers (20).

Abstract: The invention concerns a manufacturing process, and the related micromachined capacitive ultra-acoustic transducer, that uses commercial silicon wafer 8 already covered on at least one or, more preferably, on both faces by an upper layer 9 and by a lower layer 9? of silicon nitride deposited with low pressure chemical vapour deposition technique, or deposition LPCVD deposition. One of the two layers 9 or 9? of silicon nitride, of optimal quality, covering the wafer 8 is used as emitting membrane of the transducer. As a consequence, the micro-cell array 6 forming the CMUT transducer is grown onto one of the two layers of silicon nitride, i.e. it is grown at the back of the transducer with a sequence of steps that is reversed with respect to the classical technology.

Abstract: Ultrasound transducer comprising an array of electro-acoustic micro-cells, a first and a second group of transducer elements arranged substantially along two directions (x, y), each element being defined by a group of micro-cells of the array, at least part of the micro-cells of each group being electrically interconnected by a first connection pattern having shape with main orientation along one of the two directions (x, y), characterized in that each group of micro-cells defining each element comprises micro-cells interconnected by further connection pattern or patterns having shape with main orientation along the other of the two directions (y, x).

Abstract: The invention relates to an electro-acoustic transducer, particularly an ultrasonic transducer, comprising a plurality of electrostatic micro-cells of the cMUT type. The electrostatic micro-cells are arranged in homogeneous groups of micro-cells having the same geometrical characteristics. The micro-cells of each group have geometries different from the geometry of the micro-cells of the other group or groups.

Abstract: The invention concerns a manufacturing process, and the related micromachined capacitive ultra-acoustic transducer, that uses commercial silicon wafer 8 already covered on at least one or, more preferably, on both faces by an upper layer 9 and by a lower layer 9? of silicon nitride deposited with low pressure chemical vapour deposition technique, or deposition LPCVD deposition. One of the two layers 9 or 9? of silicon nitride, of optimal quality, covering the wafer 8 is used as emitting membrane of the transducer. As a consequence, the micro-cell array 6 forming the CMUT transducer is grown onto one of the two layers of silicon nitride, i.e. it is grown at the back of the transducer with a sequence of steps that is reversed with respect to the classical technology.

Abstract: The invention concerns a capacitive ultrasonic transducer, comprising an external layer operating as an external plate, provided with electrode means, capable to vibrate, and a stiff substrate, in turn provided with electrode means, wherein it further comprises n levels, with n?2, interposed between the plate and the substrate, each level including a plurality of cavities, and m interface intermediate layers, capable to vibrate, among said n levels, with m=(n?1), the cavities of each one of said n levels being further defined by support means connected between faced surfaces of layers adjacent to said cavities, each one of said m intermediate layers being provided with electrode means, whereby the cavities of each level are interposed between a pair of electrode means belonging to either two adjacent intermediate layers or to an intermediate layer and to one out of the substrate and the plate.

Abstract: The invention concerns a capacitive ultrasonic transducer, comprising an external layer operating as an external plate, provided with electrode means, capable to vibrate, and a stiff substrate, in turn provided with electrode means, wherein it further comprises n levels, with n?2, interposed between the plate and the substrate, each level including a plurality of cavities, and m interface intermediate layers, capable to vibrate, among said n levels, with m=(n?1), the cavities of each one of said n levels being further defined by support means connected between faced surfaces of layers adjacent to said cavities, each one of said m intermediate layers being provided with electrode means, whereby the cavities of each level are interposed between a pair of electrode means belonging to either two adjacent intermediate layers or to an intermediate layer and to one out of the substrate and the plate.

Abstract: The invention relates to an electro-acoustic transducer, particularly an ultrasonic transducer, comprising a plurality of electrostatic micro-cells of the cMUT type. The electrostatic micro-cells are arranged in homogeneous groups of micro-cells having the same geometrical characteristics. The micro-cells of each group have geometries different from the geometry of the micro-cells of the other group or groups.

Abstract: A surface micromachining process for manufacturing Electro-acoustic transducers, particularly ultrasonic transducers, the transducers comprising a silicon semiconductor substrate (1), on an upper surface of which one or more membranes (18) of resilient materials are supported by a structural layer (11) of insulating material, rigidly connected to the semiconductor substrate (1), the resilient material having a Young's modulus not lower than 50 GPa, the membranes (18) being metallised, the transducers including one or more lower electrodes (23, 25), rigidly connected to the semiconductor substrate. The process is characterised in that the structural layer (11) includes silicon monoxide. The invention further relates to an Electro-acoustic transducer, particularly an ultrasonic transducer, characterised in that the insulating material of the structural layer (11) is silicon monoxide.

Abstract: The invention relates to an ultrasonic transducer comprising a plurality of micro-cells, arranged in an array having M rows and N columns, and driving electronic means apt to connect in parallel to each other said micro-cells so as to form at least two sub-groups of said micro-cells, the micro-cells of each sub-group being connected in parallel to each other, at least one column of said array comprising micro-cells belonging to at least two different adjacent sub-groups, so that a radiation emitted in a direction perpendicular to the array columns by said at least one column has a phase that is intermediate between the phases of said at least two different adjacent sub-groups.

Abstract: The invention relates to a microfabricated capacitive ultrasonic transducer (20) comprising at least one thin plate (21), provided with a metallization (24), suspended over a conductive substrate (23) through supporting elements integrally coupled to the conductive substrate (23), the conductive substrate (23) forming one or more electrodes corresponding to said at least one thin plate (21), characterised in that said supporting elements comprise an ordered arrangement of columns or “pillars” (22) to which the thin plate (21) is integrally coupled, whereby the pillars (22) operate as substantially punctiform constraints. The invention further relates to a surface micro-mechanical process for fabricating such microfabricated capacitive ultrasonic transducers (20).

Abstract: This invention relates to a surface micromachining process for manufacturing Electro-acoustic transducers, particularly ultrasonic transducers, said transducers comprising a silicon semiconductor substrate (1), on an upper surface of which one or more membranes (18) of resilient materials are supported by a structural layer (11) of insulating materiel, rigidly connected to said semiconductor substrate (1), said resilient material having a Young's modulus not lower than 50 GPa, said membranes (18) being metallised, said transducers including one or more lower electrodes (23, 25), rigidly connected to said semiconductor substrate (1), the process being characterised in that said structural layer (11) includes silicon monoxide. The invention further relates to an Electro-acoustic transducer, particularly an ultrasonic transducer, characterised in that the insulating material of the structural layer (11) is silicon monoxide.

Abstract: Method for providing ultraacoustic transducers of the line curtain or point matrix type, and products obtained therefrom, wherein it is provided the step of forming a bar (10) of piezoelectric material having any length but width and thickness almost equal to each other, metalizing the faces (2, 4) of this bar (10) normal to the polarization axis, sticking one of the non-metalized faces (3) with a face of a substrate (5), depositing at least one metallic electrode (8) on both opposite faces (6, 7) of the substrate (5) normal to the face thereof connected with the bar (10), connecting these electrodes (8) with the metalized faces (2, 4) of the bar (10) by depositing a layer (9) of conductive epoxy resin on both opposite faces (6, 7) of the substrate (5) and coating the whole assembly by a complete jacket (11) of epoxy resin. (FIG. 5).

Abstract: Method for providing ultraacoustic transducers of the line curtain or point matrix type, and products obtained therefrom, comprising the steps of forming a bar of piezoelectric material having any length but width and thickness almost equal to each other, metalizing the faces of this bar normal to the polarization axis, sticking one of the non-metalized faces with a face of a substrate (5), depositing at least one metallic electrode on both opposite faces of the substrate normal to the face thereof connected with the bar, connecting these electrodes (8) with the metalized faces of the bar by depositing a layer of conductive epoxy resin on both opposite faces of the substrate and coating the whole assembly with a complete jacket of epoxy resin.