Sensing and noise characteristics of si-nanowire ion-sensitive-field-effect-transistors for future biosensor applications

Si-nanowire biologically-active field effect transistors (Si-NW BioFETs) have been considered recently for biosensing applications because the nanowire structures with the high surface-to-volume ratio are capable of detecting extremely low concentration of biomolecules in solution. Charges from specific binding of biomolecules on the surface of nanowires can affect the channel conductance of the entire volume of nanowires. In order to achieve high performance with low power consumption of the device, understanding of the sensing and noise mechanisms is very important. This work will present the pH sensing characteristics and the low-frequency noise (1/f noise) characteristics of the Si-NW BioFETs. The Si-NW BioFETs have been fabricated using well-established microfabrication technology which enables large wafer processing of sensor devices with high regularity to reduce the production costs. From the carcinoembryonic antigen (CEA) sensing performances, the sensitivity and the resolution of devices have been also discussed. This work is supported by the WCU program through the Korea Science and Engineering Foundation funded by the Ministry of Education, Science, and Technology.