Controlled force microscope for operation in liquids
US5515719A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 19, 1994 |
| Grant date | May 14, 1996 |
| Priority date | — |
| Expiry date | May 19, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S977/865
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An atomic force microscope in which the deflection of the force sensing probe owing to surface forces is canceled by an opposing magnetic force applied to a small magnetic particle on a force sensing cantilever. A deflection of the force sensing cantilever is detected by reflecting a laser beam from the cantilever into a position sensitive detector. The voltage signal from the position sensitive detector is used to drive an integrating servo loop which drives a current in a solenoid placed close to the force sensing cantilever, and exerts a force opposing the atomic force of attraction between the force sensing cantilever and the sample surface via a small magnetic particle attached to the cantilever and having its magnetic moment aligned with the axis of the solenoid. In this way, deflection of the force sensing cantilever is prevented for any force within the range of the servo control system. The driving signal for the cantilever is a measure of the operating force of the microscope and can be used to drive a conventional atomic force microscope controller to generate topographical images of the surface. The system works submerged in water and other liquids and can be used for p…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.