Multi-dimensional capacitive transducer

• US 5,661,235 A
• Filed: 12/20/1995
• Issued: 08/26/1997
• Est. Priority Date: 10/01/1993
• Status: Expired due to Term

• Current Assignee: Hysitron Incorporated (Bruker Corporation)
• Original Assignee: Hysitron Incorporated (Bruker Corporation)
• Inventors: Bonin, Wayne A.
• Primary Examiner(s): Brock, Michael
• Assistant Examiner(s): LARKIN, DANIEL SEAN
• Application Number:
  US08/579,996
• Time in Patent Office: 615 Days
• Field of Search: 73/105, 73/98, 73/81, 73/82, 73/718, 73/720, 73/724, 73/862.626, 73/862.043, 73/862.041, 73/862.68, 73/862.628, 73/862.042, 361/271, 361/280, 361/281, 361/283.1, 361/283.2, 361/283.3, 361/283.4, 177/210 C
• US Class Current: 73/105
• CPC Class Codes: G01B 7/22 using change in capacitance
• CPC Class Codes: G01B 7/34 for measuring roughness or irregularity of surfaces
• CPC Class Codes: G01D 5/2417 by varying separation
• CPC Class Codes: G01G 7/06 by electrostatic action
• CPC Class Codes: G01L 1/142 using capacitors
• CPC Class Codes: G01L 1/144 with associated circuitry G01L1/146 and G01L1/148 take precedence
• CPC Class Codes: G01L 5/165 using variations in capacitance
• CPC Class Codes: G01L 5/168 using counterbalancing forces
• CPC Class Codes: G01N 2203/0051 Piezoelectric means
• CPC Class Codes: G01N 2203/0286 Miniature specimen; Testing on microregions of a specimen
• CPC Class Codes: G01N 2203/0647 Image analysis
• CPC Class Codes: G01N 3/42 by performing impressions under a steady load by indentors, e.g. sphere, pyramid G01N3/54 takes precedence
• CPC Class Codes: G01Q 10/04 Fine scanning or positioning
• CPC Class Codes: G01Q 20/04 Self-detecting probes, i.e. wherein the probe itself generates a signal representative of its position, e.g. piezoelectric gauge
• CPC Class Codes: G01Q 60/366 Nanoindenters, i.e. wherein the indenting force is measured
• CPC Class Codes: Y10S 977/872 Positioner

Abstract

High precision force imparting and/or a force (including weight) and displacement measuring/indicating device which includes a multi-dimensional capacitor transducer system. The multi-dimensional transducer includes a first capacitive transducer for imparting force or movement and/or detecting force, weight or position in a first direction and a second capacitive transducer for imparting force or movement and/or detecting force, weight or position in a second direction. The multi-dimensional transducer may be used to provide in situ imaging in micro-mechanical test systems.

Claims

1. A high precision multi-dimensional transducer comprising:

a first capacitive transducer including means for imparting force or movement and/or detecting force, weight, or position in a first direction via a pick-up plate movably mounted relative to a drive plate therein; and

a second capacitive transducer including means for imparting force or movement and/or detecting force, weight, or position in a second direction via a pick-up plate movably mounted relative to a drive plate therein.

2. The transducer of claim 1, further wherein each transducer includes means for transmitting force between an object remote from each pick-up plate and said pick-up plate.

3. The transducer of claim 2, further comprising means responsive to the position of each pick-up plate relative to the respective drive plate for providing an output signal proportional to said relative position.

4. The transducer of claim 1, further comprising means for selectively controlling each pick-up plate.

5. The transducer of claim 4, wherein the means for selectively controlling each pick-up plate further includes means for selectively imparting a force on the remote object via the pick-up plate.

6. The transducer of claim 5, wherein the means for selectively imparting a force on the remote object via the pick-up plate includes electrostatic actuation.

7. The transducer of claim 4, wherein the means for selectively controlling each pick-up plate includes a controller having an electrostatic actuator coupled to each transducer.

8. The transducer of claim 1, further comprising a third capacitive transducer including means for imparting force or movement and/or detecting force, weight or position in a third direction having a pick-up plate movably mounted therein.

9. A high precision multi-dimensional transducer comprising:

a first capacitive transducer for imparting force or movement and/or detecting force, weight, or position in a first direction having a pick-up plate movably mounted relative to a drive plate therein;

a second capacitive transducer for imparting force or movement and/or detecting force, weight, or position in a second direction having a pick-up plate movably mounted relative to a drive plate therein;

a third capacitive transducer for imparting force or movement and/or detecting force, weight or position in a third direction having a pick-up plate movably mounted therein; and

a fourth capacitive transducer for imparting force or movement and/or detecting force, weight or position in the second direction having a pick-up plate movably mounted relative to a drive plate therein.

10. A high precision multi-dimensional transducer comprising:

a first capacitive transducer for imparting force or movement and/or detecting force, weight, or position in a first direction having a pick-up plate movably mounted relative to a drive plate therein;

a second capacitive transducer for imparting force or movement and/or detecting force, weight, or position in a second direction having a pick-up plate movably mounted relative to a drive plate therein; and

a third capacitive transducer for imparting force or movement and/or detecting force, weight or position in the second direction having a pick-up plate movably mounted relative to a drive plate therein.

11. A high precision, multi-dimensional transducer comprising:

a first capacitive transducer for detecting force, weight or position in a first direction having a pick-up plate movably mounted relative to a drive plate therein;

a second capacitive transducer for detecting force, weight or position in a second direction having a pick-up plate movably mounted relative to a drive plate therein;

means to couple each pick-up plate to a remote object; and

means to generate an output signal proportional to the force, weight or position detected.

12. The transducer of claim 11, further including means for selectively controlling the position of each pick-up plate and/or a force generated by each pick-up plate.

13. The transducer of claim 12, wherein the means for controlling the position and/or force includes electrostatic actuation.

14. The transducer of claim 12, further comprising means for drift compensation in the second direction, including a third transducer similar to the second transducer.

15. The transducer of claim 11, further comprising a third capacitive transducer including means for detecting force, weight or position in a third direction having a pick-up plate movably mounted relative to a drive plate therein.

16. In a scanned probe microscope apparatus, the improvement comprising a high precision multi-dimensional transducer including:

a first capacitive transducer including means for imparting force or movement and/or detecting force, weight or position in a first direction via a pick-up plate movably mounted relative to a drive plate therein; and

a second capacitive transducer including means for imparting force or movement and/or detecting force, weight, or position in a second direction via a pick-up plate movably mounted relative to a drive plate therein.

17. The transducer of claim 16, further wherein each transducer includes means for transmitting force between an object remote from each pick-up plate and said pick-up plate.

18. The transducer of claim 17, further comprising means responsive to the position of each pick-up plate relative to the drive plate for providing an output signal proportional to said relative position.

19. The transducer of claim 16, further comprising means for selectively controlling each pick-up plate.

20. The transducer of claim 19, wherein the means for selectively controlling each pick-up plate further includes means for selectively imparting a force on the remote object via the pick-up plate.

21. The apparatus of claim 20, wherein the means for selectively imparting a force on the remote object via the pick-up plate includes electrostatic actuation.

22. The apparatus of claim 19, wherein the means for selectively controlling each pick-up plate includes a controller having an electrostatic actuator coupled to each transducer.

23. The transducer of claim 16, further comprising a third capacitive transducer including means for imparting force or movement and/or detecting force, weight, or position in a third direction having a pick-up plate movably mounted therein.

24. In a scanned probe microscope apparatus, the improvement comprising a high precision multi-dimensional transducer including:

a first capacitive transducer for imparting force or movement and/or detecting force, weight or position in a first direction having a pick-up plate movably mounted relative to a drive plate therein;

a second capacitive transducer for imparting force or movement and/or detecting force, weight, or position in a second direction having a pick-up plate movably mounted relative to a drive plate therein; and

a third capacitive transducer for imparting force or movement and/or detecting force, weight, or position in the second direction having a pick-up plate movably mounted therein.

25. A method of performing a micro-mechanical test on a sample comprising the steps of placing the sample, and performing the micro-mechanical test using a high-precision, multi-dimensional capacitive transducer, wherein the step of performing the micro-mechanical test using the multi-dimensional capacitive transducer further comprises the steps of:

imparting force or movement and/or detecting force weight, or position in a first direction; and

imparting force or movement and/or detecting force, weight, or position in a second direction.

26. A method of performing a micro-mechanical test on a sample comprising the steps of placing the sample, and performing the micro-mechanical test using a high-precision, multi-dimensional capacitive transducer, wherein the step of performing the micro-mechanical test using the multi-dimensional capacitive transducer further comprises the steps of:

imparting force or movement and/or detecting force, weight, or position in a first direction; and

imparting force or movement and/or detecting force, weight, or position in a second direction

wherein the step of performing the micro-mechanical test using a high-precision, multi-dimensional capacitive transducer further comprises the step of imparting force or movement and/or detecting force, weight or position in a third direction.

27. In a scanned probe microscope apparatus having a piezo scanner for moving a sample relative to a tip, the improvement comprising:

means for surface imaging and multi-axis force and/or displacement measurement including a multi-dimensional transducer having,

a first capacitive transducer including means for detecting force, weight or position in a first direction having a pick-up plate movably mounted relative to a drive plate therein, and

a second capacitive transducer including means for detecting force, weight or position in a second direction having a pick-up plate movably mounted relative to a drive plate therein;

means to couple each pick-up plate to a remote object; and

means to generate an output signal proportional to the force, weight or position detected.

28. The apparatus of claim 27, further comprising means for providing application of multi-axis force and/or displacement.

29. In a scanned probe microscope apparatus, the improvement comprising:

a multi-dimensional capacitive transducer;

means coupled to the transducer for surface imaging, multi-axis force and/or displacement measurement; and

means coupled to the transducer for application of multi-axis force and/or displacement.

30. An instrument for providing high resolution surface imaging and micro-mechanical properties test, the instrument comprising:

a probe;

means for scanning, including providing relative motion between the probe and a sample, the means for scanning including a multi-dimensional transducer; and

a controller coupled to the multi-dimensional transducer, including a data acquisition and control system and an electrostatic controller.

31. The instrument of claim 30, further comprising:

a video display monitor coupled to the controller; and

a means for operator control coupled to the controller.

32. A high precision multi-dimensional transducer comprising:

a first capacitive transducer including means for imparting force or movement and/or detecting force, weight, or position in a first direction via a pick-up plate movably mounted relative to a drive plate therein;

a second capacitive transducer including means for imparting force or movement and/or detecting force, weight, or position in a second direction via a pick-up plate movably mounted relative to a drive plate therein; and

means for mechanically coupling the first capacitive transducer pick-up plate to the second capacitive transducer pick-up plate.

33. The transducer of claim 32, wherein the means for mechanically coupling includes means for maintaining each pick-up plate relatively parallel to its respective drive plate during movement of the pick-up plate.

34. The transducer of claim 32, wherein the means for mechanically coupling moves the first capacitive transducer pick-up plate in the same direction as the second capacitive transducer pick-up plate during movement of each pick-up plate.