| 摘要 |
Methods, apparatus and chip fabrication techniques are described which provide electrostatic discharge (ESD) protection to ion-sensitive field effect transistors (ISFET) based device (250) used to selectively measure ions in liquid (299). According to one aspect of the invention, an ESD protection circuit, made up of conventional protective elements (201, 202, 206), is integrated onto the same silicon chip on which ISFET (250) is formed, along with interface (203) that is in contact with liquid (299) being measured and which does not open up paths for D.C. leakage currents between ISFET (250) and liquid (299). According to a preferred embodiment of the invention, a capacitor structure is used as interface (203) between protection circuit (201, 202, 206) and liquid sample (299). Further aspects of the invention are directed to methods per se for providing ESD protection for ISFET sensors utilizing interface means (203) (e.g., capacitor structure) referred to hereinabove, and processes for fabricating the novel interface on a silicone wafer. |
