providing an intermediate assembly having a piezoelectric substrate, an acoustic matching layer of substantially uniform thickness and a front carrier plate, wherein the piezoelectric substrate has a front surface overlaid by a front electrode and a rear surface overlaid by a rear electrode, and the acoustic matching layer has a front surface and a rear surface, and wherein the front surfaces of the piezoelectric substrate and the acoustic matching layer are concave along axes perpendicular to an array axis, and wherein the acoustic matching layer is fixed between the piezoelectric substrate and the front carrier plate with the rear surface of the acoustic matching layer mounted to the concave front surface of the piezoelectric substrate;

cutting a series of substantially parallel cuts perpendicular to the array axis through the piezoelectric substrate and into the acoustic matching layer of the intermediate assembly, from the rear surface of the piezoelectric substrate, to form a plurality of individual transducer elements aligned along the array axis;

applying a backing material to the rear surface of the piezoelectric substrate of the intermediate assembly; and

removing the front carrier plate to yield an ultrasonic transducer array;

wherein the concave shapes of the front surfaces of the piezoelectric substrate and the acoustic matching layer of each transducer element are selected to mechanically focus the transducer element in a plane perpendicular to the array axis.

Abstract: An ultrasonic transducer array, and a method for manufacturing it, having a plurality of transducer elements aligned along an array axis in an imaging plane. Each transducer element includes a piezoelectric layer and one or more acoustic matching layers. The piezoelectric layer has a concave front surface overlayed by a front electrode and a rear surface overlayed by a rear electrode. The shape of each transducer element is selected such that it is mechanically focused into the imaging plane. A backing support holds the plurality of transducer elements in a predetermined relationship along the array axis such that each element is mechanically focused in the imaging plane.

U.S. Class: (73/642) (73/861.27)

IPC: (H01L 41/00)

US Patents Cited: 3666979 4281550 4326418 4424465 4523122 4546283 4734963 4747192 4869768 4992692 5042492 5042493 5044053

Related Data: This application is a division of application Ser. No. 08/010,827, filed Jan. 29, 1993, now U.S. Pat. No. 5,423,220.