SCANNING PROBE MICROSCOPE AND PROBE CONTACT DETECTION METHOD

• US 20170285067A1
• Filed: 03/24/2017
• Published: 10/05/2017
• Est. Priority Date: 03/29/2016
• Status: Active Grant

• Current Assignee: Hitachi High-Tech Science Corporation (Hitachi High- Tech Corporation)
• Original Assignee: Hitachi High-Tech Science Corporation (Hitachi High- Tech Corporation)
• Inventors: Shigeno, Masatsugu, Watanabe, Kazutoshi, Watanabe, Masafumi, Yamamoto, Hiroyoshi, Chinone, Kazuo
• Granted Patent: US 10,151,773 B2
• Time in Patent Office: Days
• CPC Class Codes: G01Q 10/02 Coarse scanning or positioning
• CPC Class Codes: G01Q 10/065 Feedback mechanisms, i.e. wherein the signal for driving the probe is modified by a signal coming from the probe itself

Abstract

According to this invention, a scanning probe microscope for scanning a surface of a sample with a probe by bringing the probe into contact with the surface of the sample, comprises a cantilever having the probe at its tip; a displacement detection unit to detect both a bending amount and a torsion amount of the cantilever; and a contact determination unit to determine a primary contact of the probe with the surface of the sample, based on the bending amount and the torsion amount detected by the displacement detection unit in all directions from an undeformed condition of the cantilever.

Claims

1. A scanning probe microscope for scanning a surface of a sample with a probe by bringing the probe into contact with the surface of the sample, comprising a cantilever having the probe at its tip;

a displacement detection unit to detect both a bending amount and a torsion amount of the cantilever; and

a contact determination unit to determine a primary contact of the probe with the surface of the sample, based on the bending amount and the torsion amount detected by the displacement detection unit in all directions from an undeformed condition of the cantilever.

2. The scanning probe microscope according to claim 1, wherein the contact determination unit determines that the probe has been brought into contact with the surface of the sample when at least one of the bending amount and the torsion amount exceeds a predetermined range.

3. The scanning probe microscope according to claim 1, further comprising a measuring unit to measure a relative distance that is a distance by which one of the probe and the surface of the sample is forced to move relative to the other when they are forced to bring into contact with each other.

4. The scanning probe microscope according to claim 3, further comprising a movement driving unit to move the probe backwards in a direction away from the sample and to move it to a next measurement position of the sample after the relative distance has been measured by the measuring unit.

5. The scanning probe microscope according to claim 3, further comprising a calculation unit to calculate a distance by which the probe is moved backwards in the direction away from the sample, based on the bending amount and the torsion amount.

6. The scanning probe microscope according to claim 4, wherein the movement driving unit, after said backwards movement, moves the probe to a before-lowering position for measurement which is positioned directly above the next measurement position and which is not brought into contact with the probe and lowers the probe from the before-lowering position for measurement to the next measurement position.

7. The scanning probe microscope according to claim 2, further comprising a movement driving unit for scanning with the probe, wherein the movement driving unit is configured to control one of the bending amount and the torsion amount detected by the displacement detection unit to be maintained within boundary values, and to control the other amount to be maintained within the predetermined range.

8. A method of detecting a probe contact of a scanning probe microscope for scanning a surface of a sample with a probe by bringing the probe into contact with the surface of the sample, comprising

a displacement detection step of detecting both a bending amount and a torsion amount of a cantilever having the probe at its tip;

and

a contact determination step of determining a primary contact of the probe with the surface of the sample, based on the bending amount and the torsion amount detected by the displacement detection step in all directions from an undeformed condition of the cantilever.