Step-gate polysilicon nanowires field effect transistor compatible with CMOS technology for label-free DNA biosensor

Gertrude Godem-Wenga (1) , Emmanuel Jacques (2) , Anne-Claire Salaün (2) , Régis Rogel (2) , Laurent Pichon (2) , Florence Geneste (3)

1 IETR - Institut d'Electronique et de Télécommunications de Rennes
2 IETR - Institut d'Électronique et des Technologies du numéRique
3 ISCR - Institut des Sciences Chimiques de Rennes

Currently, detection of DNA hybridization using fluorescence-based detection technique requires expensive optical systems and complex bioinformatics tools. Hence, the development of new low cost devices that enable direct and highly sensitive detection stimulates a lot of research efforts. Particularly, devices based on silicon nanowires are emerging as ultrasensitive electrical sensors for the direct detection of biological species thanks to their high surface to volume ratio. In this study, we propose innovative devices using step-gate polycrystalline silicon nanowire FET (poly-Si NW FETs), fabricated with simple and low cost fabrication process, and used as ultrasensitive electronic sensor for DNA hybridization. The poly-SiNWs are synthesized using the sidewall spacer formation technique. The detailed fabrication procedure for a step-gate NWFET sensor is described in this paper. No-complementary and complementary DNA sequences were clearly discriminated and detection limit to 1fM range is observed. This first result using this nano-device is promising for the development of low cost and ultrasensitive polysilicon nanowires based DNA sensors compatible with the CMOS technology.

Mots clés: Spacer formation technique; DNA hybridization; Bio-sensor; Polycrystalline silicon nanowire FET (poly-Si NW FET); CMOS compatibility

Domaines: Micro et nanotechnologies/Microélectronique

Gertrude Godem-Wenga, Emmanuel Jacques, Anne-Claire Salaün, Régis Rogel, Laurent Pichon, et al.. Step-gate polysilicon nanowires field effect transistor compatible with CMOS technology for label-free DNA biosensor. Biosensors and Bioelectronics, 2013, 40 (1), pp.141-146. ⟨10.1016/j.bios.2012.07.001⟩. ⟨hal-00787263⟩