Over the past decade, the resistance switching effect has drawn attention withinthe scientific community as a potential candidate for non-volatile random accessmemories (RAM) and crossbar logic concepts. The resistance switching memorycells are based on (at least) two well-defined non-volatile resistance states, e.g.,high resistance state (HRS) and low resistance state (LRS), that define two (ormore) logic memory states, e.g., 1 or 0. Often these cells have a simple capacitorstructure and are therefore easy to fabricate. However, the market launch ofRRAMs is hindered by several serious obstacles. For example, the underlyingmicroscopical physical and chemical switching mechanism of RRAM devicesis still under debate although various models have been proposed to explainthe observed phenomena. By missing a deep understanding of the resistiveswitching eect on an atomistic scale, a reliable fabrication of predictable andwell performing Gbit memory seems to be questionable.This thesis is an attempt to develop and physically understand the nickel oxide(NiO) based resistive switching non-volatile memory devices. Although theunderlying microscopical switching mechanism is still under debate, the macroscopicswitching mechanism of this material system is often described by thecreation and rupture of well-conducting nickel flaments embedded within aninsulating NiO matrix, the so called fuse-antifuse mechanism. The resistiveswitching characteristics, essentials for future non-volatile memories, such aslow voltage and current operation with high resistance ratio between HRS andLRS, fast switching speed, high retention and endurance are presented.Additionally, the emphasis is layed on the understanding of the so called formingprocess. It describes the first resistance transition of the resistive switchingdevice in which the proposed nickel flament is formed. Therefore, it is the keyprocess for understanding the resistive switching phenomena. The statistical distributionof the observed forming process is studied under accelerated constantvoltage stress conditions and at varying temperatures within the framework ofthe Weibull statistics.To understand the physical and chemical nature of the flamentary structure,the inuence of different ambient atmospheres and temperatures on the formingprocess is analyzed electrically as well as chemically by XPS analysis. Combiningthese results with the results of the potentiostatic breakdown studies, a modelfor the forming process in Pt/NiO/Pt non-volatile resistive switching memorydevices is proposed.
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