International Business Machines Corporation
Ion-sensitive field-effect transistor with sawtooth well to enhance sensitivity

Abstract:

A method for fabricating a semiconductor device including an ion-sensitive field-effect transistor (ISFET) with enhanced sensitivity includes forming a sawtooth microwell within a base structure formed on a semiconductor chip corresponding to an ISFET, including using a sawtooth mask to etch through the base structure to expose the semiconductor chip, removing the sawtooth mask, and forming a sawtooth macrowell from the sawtooth microwell.