Resistive Switching with Self-Rectifying Tunability and Influence of the Oxide Layer Thickness in Ni/HfO2/n+-Si RRAM Devices; Alberto Rodríguez-Fernández et al.; IEEE Trans. Electron Dev. 64 (8) pp 3159-3166 (2017). The impact of the dielectric thickness, forming polarity, and current compliance on the self-rectifying current–voltage characteristics of Ni/HfO2/n+-Si RRAM devices has been investigated. In the case of 5-nm-thick oxide devices, a self-rectifying ratio of three orders of magnitude is observed after substrate injection forming (SIF) with current compliance below 500 μA. However, devices subjected to gate injection forming (GIF) do not exhibit such rectifying feature. This distinctive behavior for SIF is ascribed to the formation of a Schottky-like contact in between the Ni-based conducting filament and the semiconductor electrode.