title: High-performance transistors for bioelectronics through tuning of channel thickness.
abstract: Despite recent interest in organic electrochemical transistors (OECTs), sparked by their straightforward fabrication and high performance, the fundamental mechanism behind their operation remains largely unexplored. OECTs use an electrolyte in direct contact with a polymer channel as part of their device structure. Hence, they offer facile integration with biological milieux and are currently used as amplifying transducers for bioelectronics. Ion exchange between electrolyte and channel is believed to take place in OECTs, although the extent of this process and its impact on device characteristics are still unknown. We show that the uptake of ions from an electrolyte into a film of poly(3,4-ethylenedioxythiophene) doped with polystyrene sulfonate (
  PSS) leads to a purely volumetric capacitance of 39 F/cm(3). This results in a dependence of the transconductance on channel thickness, a new degree of freedom that we exploit to demonstrate high-quality recordings of human brain rhythms. Our results bring to the forefront a transistor class in which performance can be tuned independently of device footprint and provide guidelines for the design of materials that will lead to state-of-the-art transistor performance.
authors.affiliation: Department of Bioelectronics, École Nationale Supérieure des Mines, CMP-EMSE, MOC, 13541 Gardanne, France.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Rivnay
authors.affiliation: Department of Bioelectronics, École Nationale Supérieure des Mines, CMP-EMSE, MOC, 13541 Gardanne, France. ; MicroVitae Technologies, Pôle d'Activité Y. Morandat, 1480 rue d'Arménie, 13120 Gardanne, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Leleux
authors.affiliation: Department of Bioelectronics, École Nationale Supérieure des Mines, CMP-EMSE, MOC, 13541 Gardanne, France.
authors.forename: Marc
authors.initials: M
authors.lastname: Ferro
authors.affiliation: Department of Bioelectronics, École Nationale Supérieure des Mines, CMP-EMSE, MOC, 13541 Gardanne, France.
authors.forename: Michele
authors.initials: M
authors.lastname: Sessolo
authors.affiliation: Aix-Marseille Université, Institut de Neurosciences des Systèmes, 13005 Marseille, France. ; INSERM, UMR_S 1106, 13005 Marseille, France.
authors.forename: Adam
authors.initials: A
authors.lastname: Williamson
authors.affiliation: Department of Bioelectronics, École Nationale Supérieure des Mines, CMP-EMSE, MOC, 13541 Gardanne, France.
authors.forename: Dimitrios A
authors.initials: DA
authors.lastname: Koutsouras
authors.affiliation: Department of Bioelectronics, École Nationale Supérieure des Mines, CMP-EMSE, MOC, 13541 Gardanne, France.
authors.forename: Dion
authors.initials: D
authors.lastname: Khodagholy
authors.affiliation: Department of Bioelectronics, École Nationale Supérieure des Mines, CMP-EMSE, MOC, 13541 Gardanne, France.
authors.forename: Marc
authors.initials: M
authors.lastname: Ramuz
authors.affiliation: Department of Bioelectronics, École Nationale Supérieure des Mines, CMP-EMSE, MOC, 13541 Gardanne, France.
authors.forename: Xenofon
authors.initials: X
authors.lastname: Strakosas
authors.affiliation: Department of Bioelectronics, École Nationale Supérieure des Mines, CMP-EMSE, MOC, 13541 Gardanne, France.
authors.forename: Roisin M
authors.initials: RM
authors.lastname: Owens
authors.affiliation: Aix-Marseille Université, Institut de Neurosciences des Systèmes, 13005 Marseille, France. ; INSERM, UMR_S 1106, 13005 Marseille, France.
authors.forename: Christian
authors.initials: C
authors.lastname: Benar
authors.affiliation: Aix-Marseille Université, Institut de Neurosciences des Systèmes, 13005 Marseille, France. ; INSERM, UMR_S 1106, 13005 Marseille, France.
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Badier
authors.affiliation: Aix-Marseille Université, Institut de Neurosciences des Systèmes, 13005 Marseille, France. ; INSERM, UMR_S 1106, 13005 Marseille, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Bernard
authors.affiliation: Department of Bioelectronics, École Nationale Supérieure des Mines, CMP-EMSE, MOC, 13541 Gardanne, France.
authors.forename: George G
authors.initials: GG
authors.lastname: Malliaras
keywords: Organic electronics; bioelectronics; electrochemical transistors