Scan control for scanning probe microscopes
US5557156A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 2, 1994 |
| Grant date | Sep 17, 1996 |
| Priority date | — |
| Expiry date | Dec 2, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S977/851
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method of controlling a scanner, particularly a scanner for use in scanning probe microscopes such as an atomic force microscope, including the steps of generating a scan voltage which varies as a parametric function of time, applying the scan voltage to the scanner, sensing plural positions of the scanner upon application of the scan voltage, fitting a parametric function to the sensed scanner positions, and controlling at least one parameter of the scan voltage function based on the parametric function fitted to the sensed scanner positions in the fitting step. In a preferred embodiment, the scan voltage is a polynomial parametric function of time and the order of terms of the polynomial is set in relation to the size of the scan being controlled, with small scans having at least one order term and relatively larger scans having plural order terms. Thus, the sensed position data are used, not to control the motion of the scanner directly in a closed loop system, but instead to optimize the transducer calibration parameters for subsequent open looped scan control of a portion of a total scan, with the calibration of the transducer scan voltage parameters periodically occurring.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.