نوع مقاله : مقاله پژوهشی
نویسنده
دانشکده مهندسی برق، واحد شبستر، دانشگاه آزاد اسلامی، شبستر، ایران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسنده [English]
Reduced graphene oxide-based field-effect transistors (rGO-FETs), due to their high surface activity, intrinsic bipolar behavior, and direct sensitivity to surface interactions, provide an efficient platform for ultrasensitive chemical and biological sensors. In this study, rGO channels were fabricated on Si/SiO₂ substrates using a solution-based spin-coating method. The structural quality of the rGO sheets was confirmed by Raman spectroscopy and SEM, demonstrating their high uniformity and structural integrity. Electrical characterization of the devices revealed stable bipolar behavior, minimal hysteresis, and ohmic contacts between Cr/Au electrodes and the rGO channel, ensuring effective modulation of the drain current by the gate voltage. The sensing performance of the rGO-FETs was evaluated against pH variations and RDX molecules; results showed significant ΔI_DS/I_DS0 changes with high reproducibility, and a concentration-dependent Dirac point shift, primarily arising from local electrostatic fields generated by the surface interactions of rGO with RDX molecules, rather than structural changes or true channel doping. Comparative analysis with previous studies indicates that the simple solution-based approach, without functionalization or complex bio-receptors, enables the fabrication of uniform channels with stable electrical performance and reliable sensing response. Compared to more complex previous methods, this approach is simpler, more scalable, and holds great potential for developing ultrasensitive sensors with high reproducibility and reliable performance.
کلیدواژهها [English]
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