Electrolyte-Insulator-Semiconductor pH Sensors with Arrayed Patterns Manufactured by Nano Imprint Technology

This work focuses on the sensing properties of electrolyte-insulator-semiconductor (EIS) pH sensors with arrayed patterns manufactured by integrating nano imprint technology (NIL) and CMOS process. The arrayed patterns, made of line and square at about ∼200-400nm with a width/space ratio of about ∼1/1-1/2, were fabricated by NIL; followed by the manufacturing of the EIS sensors. The patterns were studied by atomic force microscopy (AFM) and scanning electron microscopy (SEM). The sensors, with arrayed patterns, all exhibited higher sensitivity, lower hysteresis, and lower drift properties than the single one did. The effects of arrayed patterns (square or line) and pattern density on the sensing area were also investigated. With this approach, the sensors can be fabricated for future high performance biochemical sensing applications.