Abstract
Fabricating reference field effect transistor (FET) sensors instead of reference electrodes are important for the miniaturization and variegated applications of FET sensors. To make a reference FET, the gate surface of FET was modified with the self-assembled monolayer (SAM) of n-octadecyltrimethoxysilane (ODS). Though an ODS-SAM FET had low pH-sensitivity, it was cation-sensitive. This work demonstrates the relation between the surface morphology and the cationic and pH-sensitivity of ODS-SAM FETs. A roughness parameter of atomic force microscope images, the mean summit curvature (Ssc) has correlation with the cationic and pH-sensitivity of ODS-SAM FETs.
