Wireless SAW sensors having integrated antennas

• US 9,106,205 B2
• Filed: 12/29/2011
• Issued: 08/11/2015
• Est. Priority Date: 12/29/2010
• Status: Active Grant

• Current Assignee: University of Central Florida Research Foundation Inc. (State University System of Florida)
• Original Assignee: University of Central Florida Research Foundation Inc. (State University System of Florida)
• Inventors: Gallagher, Mark, Malocha, Donald C.
• Primary Examiner(s): SAINT SURIN, JACQUES M
• Application Number:
  US13/374,446
• Publication Number:
  US 20120174678A1
• Time in Patent Office: 1,321 Days
• Field of Search: 736/58, 736/49, 73/240.6, 73/310.6, 73/530.1, 310/313.B, 310/313.D
• US Class Current: 1/1
• CPC Class Codes: G06K 19/0675 the resonating marks being of the surface acoustic wave [SAW] kind SAW devices per se H03H9/64
• CPC Class Codes: G06K 19/07786 the antenna being of the HF type, such as a dipole
• CPC Class Codes: H03H 9/642 SAW transducers details for remote interrogation systems, e.g. surface acoustic wave transducers details for ID-tags remote interrogation systems per se G06K7/10009, G01S13/74
• CPC Class Codes: H04R 17/00 Piezoelectric transducers; Electrostrictive transducers piezoelectric or electrostrictive elements in general H10N30/00; details of piezoelectric or electrostrictive motors, generators or positioners H10N30/00
• CPC Class Codes: H04R 31/00 Apparatus or processes specially adapted for the manufacture of transducers or diaphragms therefor manufacture of microstructural arrangements of deformable or non-deformable structures in general B81C1/00182
• CPC Class Codes: Y10T 29/42 Piezoelectric device making

Abstract

A wireless surface acoustic wave sensor includes a piezoelectric substrate, a surface acoustic wave device formed on the substrate, and an antenna formed on the substrate. In some embodiments, the antenna is formed on the surface of the substrate using one or more of photolithography, thin film processing, thick film processing, plating, and printing.

Claims

1. A wireless surface acoustic wave sensor comprising:

a piezoelectric substrate having an outer surface;

a surface acoustic wave device formed on the substrate outer surface, the device comprising a transducer and a reflector grating both formed directly on the substrate;

a planar antenna formed on the substrate outer surface, wherein the antenna is wholly contained on the outer surface; and

an independent sensor formed on the substrate outer surface and interposed between the transducer and the antenna.

2. The sensor of claim 1, wherein the piezoelectric substrate is composed of one or more of quartz, lithium niobate, lithium tantalate, and lanthanum gallium silicate.

3. The sensor of claim 1, wherein the surface acoustic wave device comprises a transducer formed on the substrate outer surface.

4. The sensor of claim 3, wherein the surface acoustic wave device further comprises a reflector grating formed on the substrate outer surface.

5. The sensor of claim 3, further comprising a matching network formed on the substrate outer surface and interposed between the transducer and the antenna.

6. The sensor of claim 1, wherein the planar antenna is directly formed on the surface of the substrate using one or more of photolithography, thin film processing, thick film processing, plating, and printing.

7. The sensor of claim 1, wherein the antenna is composed of one or more of copper, titanium, gold, platinum, zirconia, or palladium.

8. The sensor of claim 1, wherein the antenna is a meandered dipole antenna.

9. The sensor of claim 1, wherein the antenna is a disk monopole antenna.

10. The sensor of claim 1, wherein the antenna is a loop antenna.

11. The sensor of claim 1, wherein the antenna is a slot antenna.

12. The sensor of claim 1, further comprising a second planar antenna formed on the substrate outer surface.

13. The sensor of claim 12, wherein the second planar antenna is formed on the same side of the substrate as the first planar antenna.

14. The sensor of claim 13, wherein the second planar antenna is orthogonal to the first antenna.

15. The sensor of claim 12, further comprising a second planar antenna the second planar antenna that is formed on a second outer surface of the substrate that is opposite to the first outer surface.

16. The sensor of claim 1, further comprising a second independent sensor formed on the substrate outer surface and interposed between the transducer and the antenna.

17. The sensor of claim 1, further comprising a matching network interposed between the transducer and the antenna.

18. The sensor of claim 17, wherein the matching network comprises a strip line and a stub.

19. The sensor of claim 18, wherein the independent sensor is connected to the stub.

20. A method for making a wireless surface acoustic wave sensor, the method comprising:

forming a piezoelectric substrate having a surface;

forming a surface acoustic wave device directly on the surface of the substrate, the device comprising a transducer and a reflector grating;

forming a planar antenna directly on the surface of the substrate using one or more of photolithography, thin film processing, thick film processing, plating, and printing such that the antenna is wholly contained on the substrate; and

forming an independent sensor directly on the surface of the substrate interposed between the transducer and the antenna.