Formation of a magnetic film on an atomic force microscope cantilever

• US 5,612,491 A
• Filed: 11/07/1995
• Issued: 03/18/1997
• Est. Priority Date: 05/19/1994
• Status: Expired due to Term

• Current Assignee: Keysight Technologies, Inc.
• Original Assignee: Molecular Imaging Corp (Agilent Technologies, Inc.)
• Inventors: Lindsay, Stuart M.
• Primary Examiner(s): Williams, Hezron E.
• Assistant Examiner(s): LARKIN, DANIEL SEAN
• Application Number:
  US08/553,111
• Time in Patent Office: 497 Days
• Field of Search: 73/105, 250/306, 250/307
• US Class Current: 73/105
• CPC Class Codes: B82Y 35/00 Methods or apparatus for measurement or analysis of nanostructures
• CPC Class Codes: G01Q 10/06 Circuits or algorithms therefor
• CPC Class Codes: G01Q 30/14 Liquid environment
• CPC Class Codes: G01Q 60/32 AC mode
• CPC Class Codes: G01Q 60/38 Probes, their manufacture, or their related instrumentation, e.g. holders
• CPC Class Codes: Y10S 977/849 with scanning probe
• CPC Class Codes: Y10S 977/851 Particular movement or positioning of scanning tip
• CPC Class Codes: Y10S 977/86 Scanning probe structure
• CPC Class Codes: Y10S 977/863 Atomic force probe
• CPC Class Codes: Y10S 977/865 Magnetic force probe
• CPC Class Codes: Y10S 977/872 Positioner
• CPC Class Codes: Y10S 977/873 Tip holder
• CPC Class Codes: Y10S 977/879 Material
• CPC Class Codes: Y10S 977/881 Microscopy or spectroscopy, e.g. sem, tem
• CPC Class Codes: Y10S 977/951 Laser

Abstract

A thin film of a magnetic material is applied to one or both surfaces of a force sensing cantilever for use in a scanning force microscope. The cantilevers are then placed between the poles of an electromagnet and a magnetizing field applied in the direction of the soft axis of the cantilevers. The field is chosen so as to be bigger than the saturation field for the magnetic film.

Claims

1. A method for magnetizing a thin film of magnetizable material disposed on a force sensing cantilever comprising:

placing the thin film of magnetizable material on the force sensing cantilever;

placing the force sensing cantilever between two opposite poles of an electromagnet; and

applying current to said electromagnet so as to generate a magnetic field between said opposite poles of said electromagnet while said force sensing cantilever is between said opposite poles.

2. A method according to claim 1 further comprising:

placing a flat calibration object between said opposite poles during the applying current step.

3. A method according to claim 2 further comprising:

using an ellipsometer to obtain a measurement of the magnetization of said flat calibration object; and

determining, from said measurement, the magnetization of said force sensing cantilever.

4. A method according to claim 1 further comprising:

forming a flat calibration object out of a non-conductive material; and

placing a thin film of magnetizable material on the flat calibration object, said film of the same material as the film placed on said force sensing cantilever, said film having the same thickness as the film placed on said force sensing cantilever, and said film having the same overall mass as the film placed on said force sensing cantilever.