Electrochemical identification of molecules in a scanning probe microscope
US5495109A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 7, 1995 |
| Grant date | Feb 27, 1996 |
| Priority date | — |
| Expiry date | Mar 7, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S977/873
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus for high resolution mapping of the chemical composition of a thin film utilizes scanning probe microscopy techniques. The sample to be studied is prepared as a thin film disposed on a conductive backing electrode. A sensitive electrometer is connected to the backing electrode to detect current passing through it. According to a first aspect of the invention, a force sensing cantilever is scanned relative to the sample surface a plurality of times. Topographic information about the sample surface is obtained in a conventional manner by studying deflections of the cantilever or feedback current used to minimize deflections of the cantilever. Simultaneously, a voltage is applied to the probe tip. This voltage, through a tunneling current to the backing electrode, causes reduction and/or oxidation reactions in the sample surface. On successive scans, different voltages may be used. In this way, the tunneling current at each of a number of different voltages for each location in the sample surface is obtained. Because specific oxidation and reduction reactions take place only at well defined voltages, it is possible, from the current measured at a certain location…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.