Studying saturation mobility, threshold voltage, and stability of PMMA-SiO2-TMSPM nano-hybrid as OFET gate dielectric

PMMA-SiO2-TMSPM (polymethyl methacrylate-silicon oxide- (3-trimethoxysilyepropyl methacrylate) nano-hybrid solutions were synthesized using sol-gel process with the constant weight ratio of PMMA-SiO2 and different weight ratios of TMSPM. Hybrid solutions were deposited on p-type Si (111) substrate using the spin coating technique. Surface morphology was studied using scanning electron microscopy (SEM) technique and the size of the nanoparticles was about 6 nm to 13 nm. Capacitance-voltage (C-f) measurements and current-voltage (I-V) curves were also studied in metal-insulator-semiconductor (MIS) structures. According to the results presented from J(GS) curves in terms of V-GS, the gate leakage current densities were small enough to be used as gate dielectric material in OFETs. At V-DS = - 10 V, in the saturation region, it is considered (transfer characteristic curves), maximum mobility mu(S,PET) was related to the sample without TMSPM because of its minimum dielectric constant. However, the surface morphology of this sample shows discontinuous nanoparticles with maximum traps on the path, which led to decreased I-DS in the channel. To overcome this challenge, other samples were produced in the presence of TMSPM as the coupling agent. The sample with 0.15 wt ratio of TMSPM has flatter surface morphology and more continuous dispersion than that of other samples so that the number of traps on the path decrease, nanoparticles distribute continuously on the surface of the thin films, and I-DS increased in the channel. By applying high gate voltages (V-GS = 80 V), according to I-DS curves in terms of V-DS, the OFETs show good stability. (C) 2016 Elsevier B.V. All rights reserved.