Development of All-Around SiO2/Al2O3 Gate, Suspended Silicon Nanowire Chemical Field Effect Transistors Si-nw-ChemFET

Abstract

We present a sensor platform associated to silicon-nanowire chemical field effect transistors (Si-nw-ChemFET). Innovations concern the use of networks of suspended silicon N+/P/N+ nanowires as conducting channel, the realization by thermal oxidation and Atomic-Layer Deposition (ALD) of a SiO2/Al2O3 gate insulator all-around the silicon nanowires, and their final integration into covered SU8-based microfluidic channels. The Si-nw-MOSFET/ChemFET fabrication process and electrical/electrochemical characterizations are presented. The fabrication process did not need an expensive and time-consuming e-beam lithography, but only fast and “low cost” standard photolithography protocols. Such microdevice will provide new opportunities for bio-chemical analysis at the micro/nanoscale.

Keywords

• ChemFET
• finFET
• MOSFET
• ISFET
• silicon nanowire
• biosensor
• potentiometric sensor
• nanosensor
• microsensor
• pH measurement
• microfluidics
• gate all-around