Ultrasound Transducer Manufactured by Using Micromachining Process, its Device, Endoscopic Ultrasound Diagnosis System Thereof, and Method for Controlling the Same

• US 20100201222A1
• Filed: 04/20/2010
• Published: 08/12/2010
• Est. Priority Date: 03/03/2006
• Status: Active Grant

• Current Assignee: Olympus Corporation
• Original Assignee: Olympus Medical Systems Corporation (Olympus Corporation)
• Inventors: Imahashi, Takuya, Mizunuma, Akiko, Adachi, Hideo, Wakabayashi, Katsuhiro, Sawada, Yukihiko, Fujimura, Takanao, Doh, Ki
• Granted Patent: US 7,982,362 B2
• Time in Patent Office: Days
• US Class Current: 310/317
• CPC Class Codes: A61B 8/12 in body cavities or body tracts, e.g. by using catheters catheters per se A61M25/00
• CPC Class Codes: A61B 8/445 Details of catheter construction
• CPC Class Codes: A61B 8/4483 characterised by features of the ultrasound transducer
• CPC Class Codes: B06B 1/0292 Electrostatic transducers, e.g. electret-type
• CPC Class Codes: B06B 1/0622 on one surface

Abstract

An ultrasound transducer manufactured by using a micromachining process comprises: a first electrode into which a control signal for transmitting ultrasound is input; a substrate on which the first electrode is formed; a second electrode that is a ground electrode facing the first electrode with a prescribed space between the first and second electrodes; a membrane on which the second electrode is formed and which vibrates and generates the ultrasound when a voltage is applied between the first and second electrodes; a piezoelectric film contacting the membrane; and a third electrode electrically continuous to the piezoelectric film.

Claims

1. An ultrasound transducer manufactured by using a micromachining process, comprising:

a first electrode into which a control signal for transmitting ultrasound is input;

a substrate on which the first electrode is formed;

a second electrode facing the first electrode;

a membrane on which the second electrode is formed and which vibrates and generates the ultrasound when voltage is applied between the first and second electrodes;

a supporting member formed by a first piezoelectric film, the supporting member being supporting the membrane; and

a third electrode jointed to the supporting member.

2. The ultrasound transducer according to claim 1, wherein:

the supporting member supports the membrane via the second electrode.

3. The ultrasound transducer according to claim 1, wherein:

a second piezoelectric film and the second electrode are stacked and arranged in sequence on an upper surface side of the membrane;

the third electrode is stacked and arranged on a bottom surface side of the membrane; and

the third electrode has a control signal input to it, wherein the control signal controls an operation of the first piezoelectric film forming the supporting member.

4. The ultrasound transducer according to claim 3, wherein:

the first piezoelectric film as the supporting member supports an end of the membrane; and

when ultrasound that has been received by the membrane is converted into a pulse signal by the second piezoelectric film, damping is performed on a tailing portion of the pulse signal by applying to the third electrode the control signal for canceling the tailing portion of the pulse signal.

5. A method of controlling an ultrasound transducer manufactured by using a micromachining process, wherein the ultrasound transducer comprises:

a first electrode into which a control signal for transmitting ultrasound is input;

a substrate on which the first electrode is formed;

a second electrode facing the first electrode;

a membrane on which the second electrode is formed and which vibrates and generates the ultrasound when voltage is applied between the first and second electrodes;

a supporting member formed by a first piezoelectric film, the supporting member being for supporting the membrane; and

a third electrode jointed to the supporting member, and wherein;

ultrasound is transmitted by deformation of the membrane vibrating on the basis of voltage applied between the first and second electrodes and by deformation of the supporting member by voltage applied to the third electrode.

6. The method of controlling an ultrasound transducer according to claim 5, wherein:

a second piezoelectric film and the second electrode are stacked and arranged in sequence on an upper surface side of the membrane;

a third electrode is stacked and arranged on a bottom surface side of the membrane; and

the second piezoelectric film detects deformation of the membrane that deforms corresponding to the control signal input into the first electrode.

7. The method of controlling an ultrasound transducer device according to claim 6, wherein:

deformation of the membrane vibrating on the basis of voltage applied between the first and second electrodes and deformation of the supporting member by voltage applied to the third electrode are superposed so that the deformations are in phase so that ultrasound is transmitted.