Akademik Veri Yönetim Sistemi
Applied Surface Science, cilt.745, 2026 (SCI-Expanded, Scopus)
Interfacial engineering of hybrid organic semiconductor systems plays a critical role in improving charge injection and transport characteristics in organic field-effect transistors (OFETs). In this study, substituent-selective interfacial electronic modulation in poly(3-hexylthiophene) (P3HT)-based OFET devices is achieved using diazonium-functionalized reduced graphene oxide (RGO) derivatives containing –NO2, –COOH, and –OH functional groups as hybrid channel modifiers. The functionalized RGO materials were synthesized via diazonium-treatment-induced surface chemical modification and incorporated into P3HT thin films deposited on pre-patterned indium tin oxide (ITO) electrodes. Devices fabricated with poly(isobutyl methacrylate) (PiBMA) dielectric layers of 100- and 150-nm thicknesses enabled evaluation of dielectric–thickness–dependent electrostatic modulation effects. Compared to pristine P3HT devices, incorporation of NO2-functionalized RGO increased the field-effect mobility from 0.86 to 1.58 cm2 V⁻1 s⁻1 for 100 nm PiBMA devices, while simultaneously reducing the threshold voltage from − 6.11 to − 2.51 V and decreasing the subthreshold swing from 0.546 to 0.446 V dec⁻1. In addition, the interface trap density decreased, and the on/off current ratio increased to 3.02 × 10⁶, indicating improved switching behavior. Devices fabricated with thicker dielectric layers (150 nm) exhibited reduced apparent mobility due to weaker electrostatic gate coupling, suggesting that dielectric scaling governs carrier accumulation while interfacial electronic modification is associated with charge-injection behavior. The observed transport behavior is consistent with substituent-dependent interfacial electronic modification associated with diazonium-treatment-induced surface chemical modification. These findings suggest a viable strategy for modulating interfacial charge-injection behavior and improving device performance.