Cantilevered probe detector with piezoelectric element

• US 8,434,160 B1
• Filed: 07/02/2012
• Issued: 04/30/2013
• Est. Priority Date: 10/01/2004
• Status: Active Grant

• Current Assignee: Board of Regents Nevada System of Higher Education (State of Nevada)
• Original Assignee: Board of Regents Nevada System of Higher Education (State of Nevada)
• Inventors: Adams, Jesse D., Sulchek, Todd A., Feigin, Stuart C.
• Primary Examiner(s): Berman, Jack
• Assistant Examiner(s): Sahu, Meenakshi
• Application Number:
  US13/539,604
• Publication Number:
  US 20130101466A1
• Time in Patent Office: 302 Days
• Field of Search: 250/234, 250/288, 422/50, 422/82.01, 422/68.01, 436/183, 436/164, 850/7, 850/57, 850/56, 850/9, 850/10, 850/59
• US Class Current: 850/56
• CPC Class Codes: G01N 2291/0257 with a layer containing at least one organic compound
• CPC Class Codes: G01N 25/00 Investigating or analyzing materials by the use of thermal means G01N3/00 - G01N23/00 take precedence
• CPC Class Codes: G01N 27/007 by investigating the electric dipolar moment measuring piezoelectric properties G01R29/22
• CPC Class Codes: G01N 29/022 Fluid sensors based on microsensors, e.g. quartz crystal-microbalance [QCM], surface acoustic wave [SAW] devices, tuning forks, cantilevers, flexural plate wave [FPW] devices microdevices per se B81B
• CPC Class Codes: G01N 29/036 by measuring frequency or resonance of acoustic waves
• CPC Class Codes: G01N 33/0031 comprising two or more sensors, e.g. a sensor array electrochemical electrode arrays G01N27/27
• CPC Class Codes: G01N 33/0057 for warfare agents or explosives properties of explosives G01N33/227
• CPC Class Codes: G01N 33/227 Explosives, e.g. combustive properties thereof detecting explosives in air G01N33/0057

Abstract

A disclosed chemical detection system for detecting a target material, such as an explosive material, can include a cantilevered probe, a probe heater coupled to the cantilevered probe, and a piezoelectric element disposed on the cantilevered probe. The piezoelectric element can be configured as a detector and/or an actuator. Detection can include, for example, detecting a movement of the cantilevered probe or a property of the cantilevered probe. The movement or a change in the property of the cantilevered probe can occur, for example, by adsorption of the target material, desorption of the target material, reaction of the target material and/or phase change of the target material. Examples of detectable movements and properties include temperature shifts, impedance shifts, and resonant frequency shifts of the cantilevered probe. The overall chemical detection system can be incorporated, for example, into a handheld explosive material detection system.

Claims

1. A chemical analyzing system comprising:

a substrate having a plurality of sensor probes, each sensor probe including an outer surface including a material that interacts with one or more target chemical species;

an electronic interface circuit that cooperates with each sensor probe to drive signals to and to sense input signals received from the sensor probes; and

a controller that controls the driving signals from and analyzes input signals sensed by the electronic interface circuit,

wherein at least one sensor probe is configured to detect, identify, and/or characterize the target chemical species via a first process and another sensor probe is configured to detect, identify, and/or characterize the target chemical species via a second process that is different than the first.

2. The system of claim 1 wherein the material of the outer surface differs from sensor probe to sensor probe.

3. The system of claim 1 wherein the sensor probes are identical except for the material of the outer surface that interacts with one or more target chemical species.

4. The system of claim 1 wherein the at least one sensor probe configured to detect, identify, and/or characterize the target chemical species via a first process includes a polymeric material that interacts with one or more target chemical species and the other sensor probe configured to detect, identify, and/or characterize the target chemical species via a second different process includes a non-polymeric material that interacts with one or more target chemical species.

5. The system of claim 1 wherein the sensor probes define an array.

6. The system of claim 1 wherein the sensor probes include one or more reference sensor probes.

7. The system of claim 1 wherein the sensor probes vary in length.

8. The system of claim 1 wherein the sensor probes include a cantilevered element.

9. The system of claim 1 wherein at least one sensor probe includes at least one element that performs drive and sense operations.

10. The system of claim 9 wherein the element that performs drive and sense operations is a piezoelectric element.

11. The system of claim 1 wherein at least one sensor probe includes a piezoelectric element that performs drive and sense operations.

12. The system of claim 1 wherein the first or second process includes where a change in mass of the target chemical species is detectable over time as the probe heater heats and evaporates the target chemical species.

13. The system of claim 1 further including another sensor probe that is configured to detect, identify, and/or characterize the target chemical species via a third process that is different than the first and second processes.

14. The system of claim 1 wherein the first process includes a plurality of processes.

15. The system of claim 14 wherein the plurality of processes are selected from selective adsorption of the target chemical species, selective absorption of the target chemical species, reaction of the target chemical species, phase change of the target chemical species, deflagration of the target chemical species, an impedance shift of one or more sensor probes among the plurality of sensor probes in the presence of the target chemical species, or any combination thereof.

16. The system of claim 1 wherein the sensor probes are connected in parallel.

17. The system of claim 1 further comprising a temperature sensor that senses the temperature of at least one of the sensor probes.

18. The system of claim 1 further comprising at least one probe heater thermally coupled to one of the sensor probes.

19. The system of claim 18 wherein the probe heater defines a temperature sensor that senses the temperature of at least one of the sensor probes.

20. The system of claim 1 further including a concentrator to concentrate the target chemical species.

21. The system of claim 20 wherein the concentrator evaporates the target chemical species when heated to increase concentration of the target chemical species proximate the sensor probe.

22. A chemical analyzing system comprising:

a substrate having a plurality of sensor probes, each sensor probe including an outer surface including a material that interacts with one or more target chemical species;

an electronic interface circuit that cooperates with each sensor probe to drive signals to and to sense input signals received from the sensor probes; and

a controller that controls the driving signals from and analyzes input signals sensed by the electronic interface circuit,

wherein a plurality of the sensor probes are configured to detect, identify, and/or characterize the target chemical species via a plurality of processes.

23. The system of claim 22 wherein the material of the outer surface of at least one sensor probe differs from another sensor probe.

24. The system of claim 22 wherein the material of the outer surface of at least one sensor probe is a polymeric material.

25. The system of claim 22 wherein the sensor probes define an array.

26. The system of claim 22 wherein at least one sensor probe includes a cantilevered element.

27. The system of claim 22 wherein at least one sensor probe includes a piezoelectric element that performs drive and sense operations.

28. The system of claim 22 wherein the plurality of processes are selected from selective adsorption of the target chemical species, selective absorption of the target chemical species, reaction of the target chemical species, phase change of the target chemical species, deflagration of the target chemical species, an impedance shift of one or more sensor probes among the plurality of sensor probes in the presence of the target chemical species, or any combination thereof.

29. The system of claim 22 wherein the sensor probes are connected in parallel.

30. The system of claim 22 further comprising a temperature sensor that senses the temperature of at least one of the sensor probes.

31. The system of claim 22 further comprising at least one probe heater thermally coupled to one of the sensor probes.

32. The system of claim 31 wherein the probe heater defines a temperature sensor that senses the temperature of at least one of the sensor probes.

33. The system of claim 22 further including a concentrator to concentrate the target chemical species.

34. The system of claim 33 wherein the concentrator evaporates the target chemical species when heated to increase concentration of the target chemical species proximate the sensor probe.

35. A chemical analyzing system comprising:

a substrate having a plurality of sensor probes defining an array, each sensor probe including an outer surface including a material that interacts with one or more target chemical species;

an electronic interface circuit that cooperates with each sensor probe to drive signals to and to sense input signals received from the sensor probes; and

a controller that controls the driving signals from and analyzes input signals sensed by the electronic interface circuit,

wherein at least one sensor probe is configured to detect, identify, and/or characterize the target chemical species via a plurality of processes and includes a polymeric material that interacts with one or more target chemical species, another sensor probe is configured to detect, identify, and/or characterize the target chemical species via a second process that is different than the plurality of processes and includes a non-polymeric material that interacts with one or more target chemical species, and another sensor probe is configured to detect, identify, and/or characterize the target chemical species via a third process that is different than the plurality of processes and second process.

36. The system of claim 35 wherein at least one sensor probe includes a piezoelectric element that performs drive and sense operations.

37. The system of claim 35 wherein the plurality of processes are selected from selective adsorption of the target chemical species, selective absorption of the target chemical species, reaction of the target chemical species, phase change of the target chemical species, deflagration of the target chemical species, an impedance shift of one or more sensor probes among the plurality of sensor probes in the presence of the target chemical species, or any combination thereof.

38. The system of claim 35 wherein the sensor probes are connected in parallel.

39. The system of claim 35 further comprising a temperature sensor that senses the temperature of at least one of the sensor probes.

40. The system of claim 35 further comprising at least one probe heater thermally coupled to one of the sensor probes.

41. The system of claim 40 wherein the probe heater defines a temperature sensor that senses the temperature of at least one of the sensor probes.

42. The system of claim 35 further comprising one or more reference sensor probes.

43. The system of claim 35 further including a concentrator to concentrate the target chemical species.

44. The system of claim 43 wherein the concentrator evaporates the target chemical species when heated to increase concentration of the target chemical species proximate the sensor probe.