Claims
- 1. A two-dimensional array of piezoelectrically actuated flextensional fluid drop ejectors comprising:a plurality of membranes of semiconductor material having a selected area, said membranes each including one or more apertures, a support structure engaging the outer edges of each of said membranes to flexibly support the membranes, said support structure and said membranes configured to form fluid reservoirs so that fluid to be ejected is in contact with said membranes, a piezoelectric transducer carried on one surface of each of said membranes surrounding said aperture, said transducer including a body of piezoelectric material having first and second spaced opposite surfaces, conductive contacts on the opposite surfaces of said body of piezoelectric material for each of said transducers for applying a voltage across said piezoelectric material to cause flextensional movement of said body of piezoelectric material whereby the associated membrane flexes responsive to applied voltage whereby the application of an ac voltage of predetermined frequency causes said membrane to resonate, and conductive means for applying said voltages across selected piezoelectric transducer to selectively bring membranes into resonance to selectively eject droplets perpendicular to the surface of said membranes through said one or more apertures.
- 2. A piezoelectrically actuated flextensional transducer as in claim 1 in which the membranes are silicon nitride.
- 3. A piezoelectrically actuated flextensional transducer as in claim 1 in which said membranes are polysilicon.
- 4. A piezoelectrically actuated flextensional transducer as in claim 1 in which said support structure is silicon oxide.
- 5. A piezoelectrically actuated flextensional transducer as in claim 1 in which said membranes are circular and said piezoelectric transducers are annular.
- 6. A piezoelectrically actuated flextensional transducer as in claim 1 in which the membranes merge to form a single membrane with multiple piezoelectric transducers.
- 7. A piezoelectrically actuated flextensional transducer as in claims 1, 2, 3, 4, or 5 in which the apertures are spaced apart a distance less than 100 μm.
- 8. A piezoelectrically actuated flextensional transducer as in claims 1, 2, 3, 4, or 5 in which the apertures are spaced apart a distance between 50 and 100 μm.
RELATED APPLICATION
This application is a continuation of co-pending application Ser. No. 09/098,011 filed Jun. 15, 1998, now U.S. Pat. No. 6,291,927, which is a continuation-in-part of application Ser. No. 08/530,919 filed Sep. 20, 1995, now U.S. Pat. No. 5,828,394 issued Oct. 27, 1998.
GOVERNMENT SUPPORT
The research leading to this invention was supported by the Defense Advanced Research Projects Agency of the Department of Defense, and was monitored by the Air Force Office of Scientific Research under Grant No. F49620-95-1-0525.
US Referenced Citations (15)
Foreign Referenced Citations (10)
Number |
Date |
Country |
0077636 |
Apr 1983 |
EP |
0542723 |
May 1993 |
EP |
59073963 |
Apr 1984 |
JP |
60068071 |
Apr 1985 |
JP |
62030048 |
Feb 1987 |
JP |
62088408 |
Apr 1987 |
JP |
WO9211050 |
Jul 1992 |
WO |
WO9301404 |
Jan 1993 |
WO |
10910 |
Jun 1993 |
WO |
WO9310910 |
Jun 1993 |
WO |
Non-Patent Literature Citations (3)
Entry |
Bernstein, J. et al., “Micromachined Ferroelectric Transducers For Acoustic Imaging,” Int'l Conference on Solid State Sensors and Actuators, Chicago, Jun. 16-19, 1997, pp. 421-424. |
Percin, G. et al., “Piezoelectrically Actuated Droplet Ejector,” Rev. Sci. Instrum. 68(12), Dec. 1997, pp. 4561-4563. |
Percin, G. et al., “Micromachined Two-Dimensional Array Piezoelectrically Actuated Transducers,” Applied Physics Letters, vol. 72., Num. 11, Mar. 16, 1998, pp. 1397-1399. |
Continuations (1)
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Number |
Date |
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Parent |
09/098011 |
Jun 1998 |
US |
Child |
09/795812 |
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US |
Continuation in Parts (1)
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Number |
Date |
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Parent |
08/530919 |
Sep 1995 |
US |
Child |
09/098011 |
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US |