%0 Journal Article
%T An influence of polyHEMA gate layer on properties of ChemFETs
%A Marek Dawgul
%A Dorota G. Pijanowska
%A Alfred Krzyskow
%A Jerzy Kruk
%A Wladyslaw Torbicz
%J Sensors
%D 2003
%I MDPI AG
%R 10.3390/s30600146
%X A complex deposition procedure of the hydrogel layer of modified poly(2-hydroxyethyl methacrylate) (polyHEMA) covalently linked to the silicon nitride surface and covering only the gate area of the ISFET, was optimized for photolithographic technology, using standard silicon wafers of 3¡± diameter. The influence of hydrogel composition and layer thickness on the sensors¡¯ parameters was investigated. It was shown, that ISFETs covered with more than 100 ¦̀m thick polyHEMA layers in restricted pH-range could be practically insensitive to pH. Regarding mechanical stability of ion-selective sensors, a polyHEMA layer of ca. 20 ¦̀m thickness was found to be the best suitable for further manufacturing of durable ion selective sensors (Chemically modified Field-Effect Transistors ¨C ChemFETs). The weak buffering properties of the thin polyHEMA layers had no disadvantageous influence on the sensors¡¯ function.
%K Ion-sensitive field-effect transistor(ISFET)
%K Poly(2-hydroxyethyl methacrylate)
%K hydrogel buffering layer
%K Photolithography
%U http://www.mdpi.com/1424-8220/3/6/146