A new design of an Electrochemical (bio)sensor: High Aspect Ratio Fin-FET

Considering the global picture of biosensing, in this work we propose a new FET design with a fin geometry with high aspect ratio for which we optimised the fabrication protocol resulting in reproducible devices with widths ranging from 100 nm to few micrometres. The developed configuration addresses the problems of nano sensors of signal to noise ratio, and reproducibility to fabrication and functionalization, without compromising much on the sensitivity and time of response in diffusion limited assays. The particular geometry of the FET channel also benefits of an intrinsic improved linearity of the transduction with concentration when the linearity does not come from the dielectric used as sensing layer, enabling wider dynamic range for the measurements. Integration with high dielectric constant materials addresses the problem of chemical stability into the fluid environment and influences the transconductance through an enhancement of the capacitive effect.