© The Author(s) 2015. Published by ECS. The possible mechanisms governing the enhancement of sensitivities of Electrolyte-insulator-semiconductor (EIS) devices upon surface modification (texturing) realized by electrostatic attachment of silica particles using 3-aminopropyl triethoxysilane (APTES) as a linker are presented. EIS devices were fabricated with a textured dielectric surface using SiO 2 particles (of diameters 475, 135, and 70 nm) and screen printed Ag/AgCl electrodes. A maximum pH sensitivity of 52.4 mV/pH was achieved for the EIS device textured with 70 nm particle size while the sensitivity with the planar dielectric was 37.1 mV/pH. The APTES modification enhanced the adsorption of H+ ions by protonation of the -NH 2 to -NH 3 + sites as seen from the capacitance versus voltage (C-V) hysteresis voltages. UV-Vis absorption and photoluminescence (PL) spectra indicated that the surface defects on the textured surface increased with decreasing particle size. Zeta potential measurements suggested a combined acid-base behavior of textured surface with the formation of -NH 3 + and -Si-O - groups. The flatband voltage study showed that surface textured with 70 nm SiO 2 particles provided the optimum ratio of Si-OH and -NH 2 groups. The various chemical treatments during texturization did not affect the characteristics at the Si/SiO 2 interface.
Kumar, N., Kumar, J., & Panda, S. (2015). Sensitivity enhancement mechanisms in textured dielectric based Electrolyte-insulator-semiconductor (EIS) sensors. ECS Journal of Solid State Science and Technology, 4(3), N18–N23. https://doi.org/10.1149/2.0141503jss