METHOD OF MANUFACTURING PIEZOELECTRIC WAFERS OF SAW IDENTIFICATION TAGS

• US 20070001857A1
• Filed: 09/12/2006
• Published: 01/04/2007
• Est. Priority Date: 01/28/2002
• Status: Abandoned Application

• Current Assignee: RF Saw Components Incorporated
• Original Assignee: RF Saw Components Incorporated
• Inventors: Brown, Paul, Hartmann, Clinton
• Application Number:
  US11/531,208
• Publication Number:
  US 20070001857A1
• Time in Patent Office: Days
• US Class Current: 340/572.100
• CPC Class Codes: G01S 13/755 using delay lines, e.g. acoustic delay lines
• 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: H03H 3/08 for the manufacture of resonators or networks using surface acoustic waves
• CPC Class Codes: H03H 9/6406 Filters characterised by a particular frequency characteristic
• CPC Class Codes: Y10T 29/42 Piezoelectric device making
• CPC Class Codes: Y10T 29/49002 Electrical device making
• CPC Class Codes: Y10T 29/49005 Acoustic transducer
• CPC Class Codes: Y10T 29/4908 Acoustic transducer

Abstract

The invention provides a method of manufacturing piezoelectric wafers of surface acoustic wave (SAW) identification tags. In one embodiment, the method includes: (1) using a master reticle to form, on each of the piezoelectric wafers, wafer-independent patterns that encode digits of a first significance for SAW identification tags; and (2) using different ones of a library of coding reticles to form, on each of the piezoelectric wafers, wafer-dependent patterns that encode digits of a second significance for SAW identification tags.

Claims

1. A method of manufacturing piezoelectric wafers of surface acoustic wave (SAW) identification tags, comprising:

using a master reticle on a stepper to form, in multiple fields across each of said piezoelectric wafers, wafer-independent patterns that encode digits of a first significance for said SAW identification tags; and

using different ones of a library of coding reticles on a stepper to form, in multiple fields across each of said piezoelectric wafers, wafer-dependent patterns that encode digits of a second significance for said SAW identification tags.

11. A method of manufacturing piezoelectric wafers of surface acoustic wave (SAW) identification tags, comprising:

establishing wafer-dependent indices for each of said piezoelectric wafers;

using a reticle on a stepper to form, in multiple fields across each of said piezoelectric wafers, wafer-independent patterns that encode digits of a first significance for said SAW identification tags; and

causing said reticle to follow said wafer-dependent indices and thereby form, in multiple fields across each of said piezoelectric wafers, wafer-dependent patterns that encode digits of a second significance for said SAW identification tags.

17. The method as recited in claim 25 wherein said reflectors are structures that reflect a surface acoustic wave.

18. The method as recited in claim 25 further comprising forming a framing reflector on said SAW identification tags, said framing reflector located between said SAW transducer and said group of slots.

19. The method as recited in claim 25 further comprising forming a plurality of said group of slots separated by dead spaces.

20. The method as recited in claim 28 wherein said plurality of group of slots is at least twelve.

2. The method as recited in claim 10 wherein said stepper is a programmable stepper.

3. The method as recited in claim 10, further comprising forming a SAW transducer on each of said SAW identification tags.

4. The method as recited in claim 10, further comprising forming said wafer-independent and wafer-dependent patterns by forming reflectors distributed among a group of slots arranged by both pulse position and by phase position, said reflectors encoding said digits of a first significance and said digits of a second significance.

5. The method as recited in claim 13 wherein said reflectors are structures that reflect a surface acoustic wave.

6. The method as recited in claim 13 further comprising forming a framing reflector on said SAW identification tags, said framing reflector located between said SAW transducer and said group of slots.

7. The method as recited in claim 13 further comprising forming a plurality of said group of slots separated by dead spaces.

8. The method as recited in claim 16 wherein said plurality of group of slots is at least twelve.

9. The method as recited in claim 13 wherein at least some of said reflectors are single strips of conductive metal.

10. The method as recited in claim 13 further comprising forming an end reflector on said SAW identification tags.

12. The method as recited in claim 20 wherein said reticle is a one power reticle.

13. The method as recited in claim 20 wherein said stepper is a programmable stepper.

15. The method as recited in claim 20, further comprising forming a SAW transducer on each of said SAW identification tags.

16. The method as recited in claim 20, further comprising forming said wafer-independent and wafer-dependent patterns by forming reflectors distributed among a group of slots arranged by both pulse position and by phase position, said reflectors encoding said digits of a first significance and said digits of a second significance.

21. The method as recited in claim 25 wherein at least some of said reflectors are single strips of conductive metal.

22. The method as recited in claim 25 further comprising forming an end reflector on said SAW identification tags.

14. The method as recited in claim 22 further comprising programing said stepper for at least one global wafer-dependent index on said wafer.