In the last decades, modern information and communication technology have become part of daily life, which is unequivocally linked with the progressive scaling of electronic components and particularly with the ongoing miniaturization of transistors and memory devices such as Flash. As the scaling limit of conventional memory technology is approaching, new concepts are part of current research. In this context, nonvolatile redox based resistive switches (Redox based Resistive Switching Random Access Memories, ReRAMs) are considered as a highly promising alternative to Flash memories. These two-terminal memory cells are based on a simple layer structure and the information is stored as different resistance levels by applying appropriate voltage pulses. In comparison to Flash, ReRAMs offer a high potential of scalability, low power consumption and fast write access. The strongly local resistive switching effect is observed in various material systems and often based on a valance change mechanism or electrochemical metallization effect. However, the processes involved during the resistance transition are not yet studied in detail, which is disadvantageous for device optimization. In this thesis, ReRAM cells based on the electrochemical metallization effect are analyzed in respect to electrochemical and physical processes, which are contributing to the resistive switching effect. Since resistive switching is observed in various materials, two different materials, i.e. silicon dioxide (SiO2) and silver iodide (AgI), representing the material class of insulators and ion conductors, respectively, were selected. In particular, nanoscale SiO2 is characterized by an unexpected high cation mobility, which is essential for the resistive switching effect but not reported in bulk SiO2. This work can be divided into two parts. In the first part, electrochemical processes prior to the switching event are analyzed by potentiodynamic and spectroscopic measurement methods. It has been observed that in SiO2 OH--ions act as counter charges, which are required for resistive switching. In case of silver iodide the Ag/AgI-interface was found to be chemically inactive, but silver can penetrate as small metal-crystallites in AgI. Moreover, in redox based resistive switches nonequilibrium states are inherently induced, which have been neglected in device models reported in literature. These effects are directly affecting the resistive switching process itself, which is studied in the second part of this thesis. Quantized conductance values have been observed both in silicon dioxide and silver iodide giving the prospect of the ultimate atomic scaling potential of ReRAMs. Additionally, the strongly nonlinear, and from an application point of view beneficial, switching kinetic is analyzed experimentally and is theoretically discussed
