Ion-sensitive field-effect transistors fabricated in a commercial CMOS technology

摘要

We report the fabrication of pH-sensitive ISFET devices in an unmodified two-metal commercial CMOS technology (1.0μm from Atmel-ES2). An ISFET amplifier circuit has also been integrated in the same chip. The ISFETs have a gate structure with afloating electrode consisting on polysilicon plus metal-1 plus metal-2. The passivation oxynitride layer acts as the pH-sensitive material in contact with the liquid solution. The devices have shown good operating characteristics, with a 46 mV/pH response.