Miniaturized potassium ion sensor
US4508613A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 19, 1983 |
| Grant date | Apr 2, 1985 |
| Priority date | — |
| Expiry date | Dec 19, 2003 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/414
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A chemically sensitive device for monitoring chemical properties is described. The device includes a depletion-mode field-effect transistor. Two electrical leads are connected between source and drain region of the field-effect transistor to monitor changes in current or potential resulting from changes in the amount of chemical to be monitored. A reference electrode is attached to a lower substrate surface of the field-effect transistor and electrically connected to the source via a highly doped region adjacent to the source and another highly doped region adjacent to the reference electrode, both having a polarity identical to the substrate. A sensing membrane which is specific to the chemical to be monitored is located on a portion of the substrate remote from the gate region but electrically connected to the gate region to alter conductance between the source and the drain in accordance with the presence or absence of the chemical to be monitored. Thus, the source, gate, drain regions may be completely encapsulated to prevent contamination of the FET by the chemical to be monitored.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.