Nitrogen-Oxyanion-Doped HfO2 Resistive Random-Access Memory With Chemically Enhanced Forming

The high forming voltage of resistive random-access memory (RRAM) is one of the key bottlenecks for its integration in advanced silicon technology nodes. Here a nitrogen-oxyanion-doped (N-doped) hafnium oxide (HfO2) RRAM with overall improvement on forming voltage, on/off ratio and endurance is demonstrated. The critical electric field of N-doped RRAM for forming is 40% less than that of undoped RRAM. Therefore, a thicker resistive switch-ing layer (RSL) can be used to obtain the same forming voltage, which benefits the on/off ratio and endurance per-formance. The N-doped RRAM achieves 3x improvement in on/off ratio and 10x improvement in endurance at the forming voltage of 2 V, a value applicable for integration with advanced silicon technology node. We propose the hypothesis that the nitrites ((NO2)(-)) in the RSL of N-doped devices promote forming through introducing extra chemi-cal process as well as additional conductive paths. Physical characterization and first-principles calculations are further carried out to validate our hypothesis.

Automated summary

A nitrogen-oxyanion-doped hafnium oxide RRAM with improved forming voltage, on/off ratio, and endurance is demonstrated. The critical electric field of N-doped RRAM for forming is 40% lower than that of undoped RRAM. The N-doped RRAM achieves 3x improvement in on/off ratio and 10x improvement in endurance at the forming voltage of 2 V, which is suitable for integration with advanced silicon technology nodes.