Characterization of the doped silicon dioxide and its implications on the resistive switching phenomena in the electrochemical metallization cells

Abstract

In this Master's thesis, the switching behavior of the doped and undoped SiO2-based memory cells was compared. The aim of doping was to enhance the switching behavior of the ECM memory cells. About 270 samples were sputtered using the CT1000 cluster deposition tool in the IWE2 of RWTH Aachen University. For the deposition of the thin films, the platinum, titanium nitride and Al2O3 substrates were used. The deposition was performed by using three differently doped targets. The physical characterization of the thin films was done using SEM, XRR, XRD, and EDX. Electroforming and electric characterization of the fabricated memory cells were made in the probe station with the light microscope and the Keithley electrometer. The results of the physical and electrical characterization were analyzed using the principle of Exploratory Data Analysis (EDA). The analysis of the result shows that two undoped samples on the platinum substrate and some doped samples exhibit the unexpected volatile threshold switching of metallic and semiconductive origin, respectively. Linear fitting of the measurement data in a logarithmic scale suggests that Schottky- and Frenkel- Poole conduction mechanisms are not dominant.