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Redox-based resistive switching is one of the most-promising concepts in the focus of research to meet the ever-growing demand for faster and smaller non-volatile memory devices. In this work we present detailed studies of the impact of cation stoichiometry and surface segregation effects on the performance of the valence change memory model material SrTiO3. In order to clarify if the enhanced switching performance of Sr-rich SrTiO3 devices can be attributed to SrO segregation or to the formation of Sr-rich extended defects, we artificially engineered the formation of SrO islands by depositing additional SrO on top of stoichiometric SrTiO3. We thereby unravel that the enhanced switching performance is solely accounted for by the formation of SrO islands and not influenced by extended defects. Consequently following our findings, we design devices with a further improved retention by tailoring the amount of SrO on the surface.

We have studied the bonding and elastic properties of amorphous AlYB 14 using theoretical and experimental means. Based on pair distribution functions and Voronoi tessellation, the icosahedral bonding is expected. A rather large Young's modulus of 365 GPa is predicted for amorphous AlYB 14 . To verify these predictions, we have measured density, pair distribution functions, binding energy and elastic properties of Al–Y–B thin films synthesized by magnetron sputtering. The calculated and measured densities are with a deviation of 3.5% in good agreement. The measured binding energy and pair distribution functions are also consistent with icosahedral bonding. The measured Young's modulus is 305±19 GPa, which is 16% smaller than the theoretical value and hence in good agreement. Overall consistency between theory and experiments was obtained indicating that the computational strategy employed here is useful to describe correlations between bonding, elasticity, density as well as (chemical) short range order and may hence enable future knowledge-based design of these ternary borides which show great potential for surface protection applications.