Bio-inspired adaptive sensing through electropolymerization of organic\n electrochemical transistors

Abstract

Organic Electrochemical Transistors are considered today as a key technology\nto interact with biological medium through their intrinsic ionic-electronic\ncoupling. In this paper, we show how this coupling can be finely tuned (in\noperando) post-microfabrication via electropolymerization technique. This\nstrategy exploits the concept of adaptive sensing where both transconductance\nand impedance are tunable and can be modified on-demand to match different\nsensing requirements. Material investigation through Raman spectroscopy, atomic\nforce microscopy and scanning electron microscopy reveals that\nelectropolymerization can lead to a fine control of PEDOT microdomains\norganization, which directly affect the iono-electronic properties of OECTs. We\nfurther highlight how volumetric capacitance and effective mobility of\nPEDOT:PSS influence distinctively the transconductance and impedance of OECTs.\nThis approach shows to improve the transconductance by 150% while reducing\ntheir variability by 60% in comparison with standard spin-coated OECTs.\nFinally, we show how to the technique can influence voltage spike rate hardware\nclassificationwith direct interest in bio-signals sorting applications.\n