ISFET´s with ion-sensitive membranes fabricated by ion implantation

Author

Ito, Tadashi ; Inagaki, Hazime ; Igarashi, Isemi

Author_Institution

Toyota Central Res. & Dev. Labs., Aichi, Japan

Volume

35

Issue

1

fYear

1988

fDate

1/1/1988 12:00:00 AM

Firstpage

56

Lastpage

64

Abstract

Ion sensitive FETs (ISFETs) for sodium ions (Na⁺) fabricated by ion-implantation are investigated. The sensing layers are produced by implanting Na⁺ ions into the surface of an oxidized Si₃N₄ layer through an Al buffer layer deposited beforehand, in order to reduce the damage to the gate insulator of the ISFET during ion implantation. The Na⁺ sensitivity, selectivity, repeatability, thermal characteristics, and long-term stability are evaluated. The ISFET responds to Na⁺ ions independent of pH within the range of pH 7-10, and the Na⁺ sensitivity is nearly Nernstian. The ISFETs repeatability and long-term stability (about 1300 h), suggests that the ion-implantation technique is a suitable method for fabricating a stable ion-sensing layer

Keywords

chemical variables measurement; electric sensing devices; insulated gate field effect transistors; ion implantation; 1300 h; Al buffer layer; ISFETs; Na⁺ sensitivity; Si-SiO₂-Si₃N₄; ion implantation; ion sensitive FET; ion-sensitive membranes; long-term stability; repeatability; selectivity; thermal characteristics; Artificial intelligence; Biomembranes; Electrodes; Fabrication; Glass; Indium tin oxide; Insulation; Ion implantation; Thermal stability; Windows;

fLanguage

English

Journal_Title

Electron Devices, IEEE Transactions on

Publisher

ieee

ISSN

0018-9383

Type

jour

DOI

10.1109/16.2415

Filename

2415