Investigation of Switching mechanism Thermal Electrochemical and Structural properties of Solid Electrolytic Superionic α-AgI based Silver Molybdate glass for Resistive Memory RRAM Applications

Abstract

Developing efficient, fast performing and thermally stable AgI-Ag2O-MoO3glasses are of great interest for Resistive Random Access Memory (RRAM) applications; however there many challenges such as metallization in bulk, behavior of Vth profile over composition and corrosion reactions. In this thesis work, fast ion conducting (FIC) AgI-Ag2O-MoO3 glasses have been investigated with an idea to solve some technical challenges such as thermal stability, corrosion etc. with the help of deep understanding of the material. Employing various experimental and characterization techniques, this research work aims to identify the links between various material and technical aspects and how to tune these aspects to solve the challenges envisaged. Bulk AgI-Ag2O-MoO3 (50:25:25) glasses have been prepared by melt quenching method (Microwave heating and quenched between two heavy steel plates). The electrical switching experiments have been carried out using a Keithley Source Meter (model 2410) controlled by Lab VIEW 6i, on samples of thicknesses (d) 0.1, 0.2 and 0.3 mm at different ON state currents (Imax) (3 mA, 2 mA, 1 mA, 0.6 mA, 0.4 mA and 0.25 mA); It has been found that these samples exhibit fast near ideal memory switching. The power dissipation (P) increases with both d and Imax. It is also found that the threshold voltage (Vth) increases with d; and for a given thickness, the Vth decreases with increasing Imax. A sample of d = 0.1 mm exhibits near ideal memory switching with the least P for Imax = 0.25 mA. These samples can be used for fast switching applications with minimum power dissipation. Further, the electrical switching behavior of bulk, FIC (AgI)50+x-(Ag2O)25-(MoO3)25-x, for 10 and#8804; x and#8804; -10 glasses has been investigated, in order to understand the switching mechanism of bulk samples with the inert electrodes. It is found that by using inert electrodes, the switching becomes irreversible, memory type. In these samples, the switching mechanism is an electrochemical metallization process...