Force sensing probe for scanning probe microscopy

• US 6,121,611 A
• Filed: 05/20/1998
• Issued: 09/19/2000
• Est. Priority Date: 05/20/1998
• Status: Expired due to Term

• Current Assignee: Keysight Technologies, Inc., Arizona Board of Regents (University of Arizona)
• Original Assignee: Molecular Devices, Arizona Board of Regents (University of Arizona)
• Inventors: Jing, Tianwei, Lindsay, Stuart M.
• Primary Examiner(s): NGUYEN, KIET TUAN
• Application Number:
  US09/082,095
• Time in Patent Office: 853 Days
• Field of Search: 250/306, 250/307, 73/105, 324/252
• US Class Current: 850/59
• CPC Class Codes: G01Q 60/40 Conductive probes
• CPC Class Codes: G01Q 70/14 Particular materials
• CPC Class Codes: Y10S 977/865 Magnetic force probe
• CPC Class Codes: Y10S 977/873 Tip holder

Abstract

Force sensing probes for use in scanning probe microscopes and a method for coating such probes with a film comprising a magnetostrictive material are provided. The probes may be magnetized by placing them in a magnetic field which can be oriented in any direction with respect to the probes. The magnetostrictive effect leads to a compression or expansion of the magnetic film, altering its length by the strength of the applied field. This in turn causes the probe, which in a preferred embodiment is in the form of a cantilever, and the applied magnetic film, to deflect or bend. The consequent motion of the probe is much greater than that obtained by direct application of a magnetic force and the effect is not sensitive to the direction of the applied field.

Claims

1. A force sensing probe for sensing the properties of a surface or interface comprising a probe and a film comprising a magnetostrictive material on said probe.

2. A force sensing probe as claimed in claim 1 in which said magnetostrictive material comprises material selected from the group consisting of nickel;

cobalt;

alloys and mixtures of terbium and iron;

alloys and mixtures of iron, neodymium and boron;

alloys and mixtures of nickel and iron;

alloys and mixtures of cobalt and iron;

alloys and mixtures of nickel and vanadium;

alloys and mixtures of nickel and chrome;

alloys and mixtures of nickel and manganese;

alloys and mixtures of nickel and cobalt;

alloys and mixtures of nickel and copper;

alloys and mixtures of beryllium and iron;

alloys and mixtures of aluminum and iron;

alloys and mixtures of germanium and iron;

alloys and mixtures of silicon and iron;

alloys and mixtures of the oxides of titanium and iron;

alloys and mixtures of the oxides of manganese and iron;

alloys and mixtures of the oxides of cobalt and iron;

alloys and mixtures of the oxides of copper and iron;

alloys and mixtures of the oxides of barium and iron; and

alloys and mixtures of the oxides of strontium and iron.

3. A force sensing probe as claimed in claim 1 in which said probe comprises a cantilever having a top surface and a bottom surface, said bottom surface including a probe tip disposed downwardly therefrom.

4. A force sensing probe as claimed in claim 3 in which said magnetostrictive material is coated onto said top surface of said cantilever.

5. A force sensing probe as claimed in claim 4 in which cantilever includes a coating comprising a different material disposed over said bottom surface and said probe tip.

6. A force sensing probe as claimed in claim 5 in which said different material comprises a magnetostrictive material.

7. A force sensing cantilever for an atomic force microscope comprising a cantilever structure having a top surface and a bottom surface, said bottom surface including a probe tip disposed downwardly therefrom, a film comprising a magnetostrictive material coated onto one of said surfaces and a film comprising a different material coated onto the other of said surfaces.

8. A force sensing cantilever as claimed in claim 7 in which said different material comprises a magnetostrictive material.

9. A force sensing cantilever as claimed in claim 7 in which said magnetostrictive material is coated onto said top surface of said cantilever.

10. A force sensing cantilever as claimed in claim 9 in which said magnetostrictive material is coated onto said bottom surface of said cantilever and over said probe tip.

11. A scanning probe microscope for sensing the properties of a surface or interface comprising a probe, a film comprising a magnetostrictive material on said probe, a source for producing a magnetic field to cause deflection of said probe, and a detector for sensing the deflection of said probe.

12. A scanning probe microscope as claimed in claim 11 in which said magnetostrictive material comprises material selected from the group consisting of nickel;

cobalt;

alloys and mixtures of terbium and iron;

alloys and mixtures of iron, neodymium and boron;

alloys and mixtures of nickel and iron;

alloys and mixtures of cobalt and iron;

alloys and mixtures of nickel and vanadium;

alloys and mixtures of nickel and chrome;

alloys and mixtures of nickel and manganese;

alloys and mixtures of nickel and cobalt;

alloys and mixtures of nickel and copper;

alloys and mixtures of beryllium and iron;

alloys and mixtures of aluminum and iron;

alloys and mixtures of germanium and iron;

alloys and mixtures of silicon and iron;

alloys and mixtures of the oxides of titanium and iron;

alloys and mixtures of the oxides of manganese and iron;

alloys and mixtures of the oxides of cobalt and iron;

alloys and mixtures of the oxides of copper and iron;

alloys and mixtures of the oxides of barium and iron; and

alloys and mixtures of the oxides of strontium and iron.

13. A scanning probe microscope as claimed in claim 11 in which said probe comprises a cantilever having a top surface and a bottom surface, said bottom surface including a probe tip disposed downwardly therefrom.

14. A scanning probe microscope as claimed in claim 13 in which said magnetostrictive material is coated onto said top surface of said cantilever.

15. A scanning probe microscope as claimed in claim 14 in which cantilever includes a coating comprising a different material disposed over said bottom surface and said probe tip.

16. A scanning probe microscope as claimed in claim 15 in which said different material comprises a magnetostrictive material.

17. A method of magnetizing a probe for sensing the properties of a surface or interface comprising the steps of forming a film comprising a magnetostrictive material on a surface of said probe and exposing said probe to a magnetic field in the range of from about 0.1 to about 20,000 Oersteds.

18. A method as claimed in claim 17 in which said magnetostrictive material comprises material selected from the group consisting of nickel;

cobalt;

alloys and mixtures of terbium and iron;

alloys and mixtures of iron, neodymium and boron;

alloys and mixtures of nickel and iron;

alloys and mixtures of cobalt and iron;

alloys and mixtures of nickel and vanadium;

alloys and mixtures of nickel and chrome;

alloys and mixtures of nickel and manganese;

alloys and mixtures of nickel and cobalt;

alloys and mixtures of nickel and copper;

alloys and mixtures of beryllium and iron;

alloys and mixtures of aluminum and iron;

alloys and mixtures of germanium and iron;

alloys and mixtures of silicon and iron;

alloys and mixtures of the oxides of titanium and iron;

alloys and mixtures of the oxides of manganese and iron;

alloys and mixtures of the oxides of cobalt and iron;

alloys and mixtures of the oxides of copper and iron;

alloys and mixtures of the oxides of barium and iron; and

alloys and mixtures of the oxides of strontium and iron.

19. A method as claimed in claim 18 in which said probe comprises a cantilever having a top surface and a bottom surface, said bottom surface including a probe tip disposed downwardly therefrom.

20. A method as claimed in claim 19 in which said magnetostrictive material is coated onto said top surface of said cantilever.

21. A method as claimed in claim 20 in which cantilever includes a coating comprising a different material disposed over said bottom surface and said probe tip.

22. A method as claimed in claim 21 in which said different material comprises a magnetostrictive material.

23. A method of magnetizing a force sensing cantilever for a scanning probe microscope comprising the steps of:

forming a cantilever having a top surface, a bottom surface and a probe tip extending downwardly from said bottom surface;

sputter depositing a first film comprising a magnetostrictive material onto said bottom surface of said cantilever; and

sputter depositing a second film comprising a different material onto said top surface of said cantilever.

24. A method as claimed in claim 23 in which said magnetostrictive material is coated onto said top surface of said cantilever.

25. A method as claimed in claim 24 in which said magnetostrictive material is coated onto said bottom surface of said cantilever and over said probe tip.

26. A method as claimed in claim 23 in which said magnetostrictive material comprises material selected from the group consisting of nickel;

cobalt;

alloys and mixtures of terbium and iron;

alloys and mixtures of iron, neodymium and boron;

alloys and mixtures of nickel and iron;

alloys and mixtures of cobalt and iron;

alloys and mixtures of nickel and vanadium;

alloys and mixtures of nickel and chrome;

alloys and mixtures of nickel and manganese;

alloys and mixtures of nickel and cobalt;

alloys and mixtures of nickel and copper;

alloys and mixtures of beryllium and iron;

alloys and mixtures of aluminum and iron;

alloys and mixtures of germanium and iron;

alloys and mixtures of silicon and iron;

alloys and mixtures of the oxides of titanium and iron;

alloys and mixtures of the oxides of manganese and iron;

alloys and mixtures of the oxides of cobalt and iron;

alloys and mixtures of the oxides of copper and iron;

alloys and mixtures of the oxides of barium and iron; and

alloys and mixtures of the oxides of strontium and iron.