Optical, mechanical and dielectric properties of sol-gel PMMA-GPTMS-ZrO₂ hybrid thin films with variable GPTMS content

We report the synthesis, characterization, and dielectric gate application of organic-inorganic PMMA-GPTMS-ZrO₂ hybrid films, where GPTMS (3-glycidyloxypropyl(trimethoxy)silane) is the coupling agent. Three hybrid films were deposited by sol-gel varying the GPTMS concentration in the precursor solution, and their properties were analyzed by UV-Vis, FTIR, TGA, AFM, FE-SEM, EDS, XPS, and nanoindentation. Their electrical properties were measured on MIM devices. The homogeneity and high optical transparency of the hybrid films bear out the achievement of cross-linked organic-inorganic phases. The optical, mechanical, and dielectric properties of the hybrid films depend on the amount of GPTMS in their composition. The refractive index, mechanical hardness, elastic modulus, and dielectric constant of the hybrid films varied in the ranges of 1.54-1.61, 2.2-2.7 GPa, 87-123 GPa, and 7.6-13.6, respectively, depending on the GPTMS amount. The hybrid films were applied as dielectric gate in TFTs with ZnO as the semiconductor exhibiting good performance at low operating voltages.