Influence of Gate Voltage Operation on Effective Mobility of Electrolyte-Gated Organic Transistors

Low-voltage operation has long been a beneficial characteristic of electrolyte-gated organic transistors (EGOTs) because of the high capacitance of the electrolyte dielectric layer. Operating below 3 V, several reported EGOTs have effective mobilities above 1 cm(2) V-1 s(-1) based on the recently introduced reliability factor for organic field-effect transistors (OFETs). In this study, we report on the influence of gate voltage operation on the effective mobilities of EGOTs using poly(3-hexylth-iophene) (P3HT) semiconductor and electrolyte dielectric operating at different gate voltages of -1, -1.5, and -2 V. Average field-effect mobilities (mu(FET)) of 2.35 +/- 0.41 (2.39 +/- 0.27), 3.74 +/- 0.33 (2.95 +/- 0.32), and 3.30 +/- 0.44 (2.81 +/- 0.38) cm(2) V-1 s(-1) are measured in the saturation (linear) regimes for devices operating at -1, -1.5 and -2 V, respectively. With a reliability factor of 74.9 +/- 2.8% (86.2 +/- 2.2%) in the saturation (linear) regime, devices at -1.5 V measured the highest average effective mobility (mu(eff)) of 2.79 +/- 0.22 (2.54 +/- 0.29) cm(2) V-1 s(-1) in the saturation (linear) regime due to efficient charge transport with minimal charge scattering. Our results highlight fundamental optimization techniques helpful for achieving optimal effects.

Automated summary

This study investigated the influence of gate voltage operation on the effective mobilities of EGOTs. The results showed that devices operated at -1.5V gate voltage exhibited the highest average effective mobility and the highest reliability factor, which can be attributed to efficient charge transport and minimal charge scattering.