Data accompanying the paper: Prodromakis, Themistoklis; Trapatseli, Maria; Cortese, Simone; Serb, Alexantrou / Improved switching characteristics of TiO2-x ReRAM with embedded ultra-thin 2 Al2O3-y layers. In: Journal of Applied Physics, 28.03.2017. Abstract for accompanying paper: Transition metal-oxide resistive random access memory (RRAM) devices have demonstrated excellent performance in switching speed, versatility of switching and low-power operation. However, this technology still faces challenges like poor cycling endurance, degradation due to high electro-forming switching voltages and low yields. Engineering of the active layer by doping or addition of thin oxide buffer layers, are approaches that have been often adopted to tackle these problems. Here, we have followed a strategy that combines the two; we have used ultra-thin Al2O3-y buffer layers incorporated between TiO2-x thin films taking into account both 3þ/4þ oxidation states of Al/Ti cations. Our devices were tested by DC and pulsed voltage sweeping and in both cases demonstrated improved switching voltages. We believe that the Al2O3-y layers act as reservoirs of oxygen vacancies which are injected during EF, facilitate a filamentary switching mechanism and provide enhanced filament stability as shown by the cycling endurance measurements.