Micromachined imaging transducer
AssigneeSciMed Life Systems, Inc.
InventorsPaul W. Rehrig, Xiaoning Jiang, Wesley S. Hackenberger, Jian R. Yuan, Richard Romley
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Abstract
The present invention generally relates to medical devices, and more particularly to an improved medical imaging device. In one embodiment, an imaging device includes a drive shaft having proximal and distal ends received within the lumen; and an imaging transducer assembly coupled to the distal end of the drive shaft and positioned at the distal portion of the elongate member. The imaging transducer assembly includes one or more imaging transducers formed with a piezoelectric composite plate using photolithography based micromachining.
Claims23
An imaging device configured to be located in an imaging catheter, said imaging device comprising:
- a drive shaft having proximal and distal ends;
- and
- an imaging transducer assembly coupled to the drive shaft, wherein the imaging transducer assembly includes one or more imaging transducers, wherein the one or more imaging transducers are formed from a photolithography based micromachined piezoelectric composite plate, the piezoelectric composite plate including a single crystal piezoelectric, wherein each imaging transducer includes a plurality of posts and each of the plurality of posts has an aspect ratio of post height to post width of at least 2 to 1.
A method for fabricating one or more imaging transducers, comprising the steps of:
- using photolithography based micromachining to form a plurality of posts on a piezoelectric material plate, wherein the step of forming a plurality of posts on a piezoelectric material plate using photolithography based micromachining comprises
- forming a hard metal mask over portions of the plate where the plurality of posts are to be formed;
- and
- etching portions of the plate exposed by the hard mask to form a plurality of kerfs between the posts, wherein the kerfs do not extend through the plate after the etching and wherein the posts have an aspect ratio of at least 2 to 1 and a vertical etching profile of at least 80°;
- and
- filling the plurality of kerfs surrounding the plurality of posts with a polymeric material;
- wherein the one or more imaging transducers are ultrasound transducers.
A method for fabricating one or more imaging transducers, comprising the steps of:
- using photolithography based micromachining to form a plurality of posts on a piezoelectric material plate, wherein the step of forming a plurality of posts on a piezoelectric material plate using photolithography based micromachining comprises
- forming a hard metal mask over portions of the plate where the plurality of posts are to be formed;
- and
- selectively etching portions of the plate exposed by the hard mask to form a plurality of kerfs surrounding the post, wherein, after the etching of the portions of the plate, an upper portion of each post is separated from an upper portion of adjacent posts only by the plurality of kerfs;
- and
- filling the plurality of kerfs surrounding the plurality of posts with a polymeric material;
- wherein the one or more imaging transducers includes a plurality of posts and kerfs, wherein each of the plurality of posts has a width in the range of approximately 3 to 36 μm, an aspect ratio of at least 2 to 1, and a vertical etching profile of at least 80°, and each of the plurality of kerfs has a width in the range of approximately 1 to 15 μm.
Dependencies are inferred from the claim text.