Method of monitoring radiation using a floating gate field effect transistor dosimeter, and dosimeter for use therein
US6172368A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Aug 24, 1998 |
| Grant date | Jan 9, 2001 |
| Priority date | — |
| Expiry date | Aug 24, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01T1/026
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
An insulated gate field effect transistor dosimeter has a source and drain defining a channel region, a floating gate having a first portion extending over the channel region, and a second, larger portion extending away from said region, a control gate having at least a portion thereof overlapping a first part of the floating gate, and a charging gate overlapping a second part of the floating gate. The area of the second part of the floating gate is much smaller than the area of the first part, and the charging gate is separated from the channel region by the control gate. The dosimeter is charged, before irradiation, by connecting the source, drain and control gate to a common ground and applying a potential difference between the charging gate and the common ground. The charge is supplied to the floating gate by a path which does not require a significant electric stress to be created in the region of the gate oxide and the channel. The dosimeter may comprise two such transistors fabricated on a common substrate, conveniently with a common source. The pair of transistors may be charged by maintaining the sources, drains and control gates within the normal maximum operating voltag…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.