Geometrical Optimization of Organic Electrochemical Transistor for High Transconductance

Organic electrochemical transistors (OECTs) are used widely as active devices for biosensing applications. OECT geometry can also be optimized by modifying the parameters like channel thickness and width to length ratio of the device to achieve optimum performance. The geometrical optimization of the OECT was conducted in this work using poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS) as the channel material. The fabricated OECTs demonstrate a ON/OFF current ratio (1.1 x 10(3)) and mu C* of 219.1 27.5 F cm(-1)V(-1)s(-1). The devices with a higher width/length (W/L) ratio and a thicker channel of 260 nm demonstrate a transconductance of 2.17 mS. Pulse measurements were conducted on 260 nm thick PEDOT:PSS demonstrate high volumetric capacitance and hole mobility of 57.11 1.92 F cm(-3)and similar to 4 cm(2)V(-1)s(-1)respectively.