Atomic force microscope
US5224376A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 6, 1992 |
| Grant date | Jul 6, 1993 |
| Priority date | — |
| Expiry date | Feb 6, 2012 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S977/851
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
This invention is an atomic force microscope having a digitally calculated feedback system which can perform force spectroscopy on a sample in order to map out the local stiffness of the sample in addition to providing the topography of the sample. It consists of a three-dimensional piezoelectric scanner, scanning either the sample or a force sensor. The force sensor is a contact type with a tip mounted on a cantilever and a sensor to detect the deflection of the lever at the tip. The signal from the sensor goes to an A-D convertor and is then processed by high-speed digital electronics to control the vertical motion of the sample or sensor. In operation, the digital electronics raise and lower the piezoelectric scanner during the scan to increase and decrease the force of the tip on the sample and to use the sensor signal to indicate the change in height of the tip to measure the which is the spring constant of the sample. This constant can be determined with nanometer spatial resolution. At the same time, the instrument can determine the topography of the sample with nanometer resolution. In an alternate embodiment, the lever is connected to a separate piezoelectric driver to var…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.