Low-damage NH3 plasma treatment on SiO2 tunneling oxide of chemically-synthesized gold nanoparticle nonvolatile memory

•Low-damage NH3 plasma treatment on SiO2 tunneling oxide (TO) of CS Au-NP memories.•Trapezoid-like energy band diagram of NH3 plasma-treated TO layer examined by XPS.•Programming correlated with Au-NP dot density and TO band structure by NH3 plasma.•Low charge loss of NH3 plasma-treated memories due to band engineering of TO layer.

Characteristics of chemically-synthesized (CS) gold nanoparticle (Au-NP) nonvolatile memories (NVMs) with low-damage NH3 plasma treatment on a tunneling oxide (TO) layer have been investigated. Although the dot density of CS Au-NPs is decreased, the programming efficiency of memories with optimized NH3 plasma treatment condition is enhanced due to the formation of a trapezoid-like energy band diagram of the TO layer by nitrogen incorporation. With the extraction of relative permittivity and electron affinity of the TO layer, the capacitance-voltage (C-V) and programming behaviors of CS Au-NP memories with low-damage NH3 plasma treatment on the TO layer are well-fitted by the TCAD (Technology Computer-Aided-Design) simulation. Further, the built-in electric field induced by the trapezoid-like energy band diagram of the TO layer can suppress the leakage current of the TO layer, thereby improving the data retention properties. The low-damage NH3 plasma treatment that results in no plasma damage to the TO layer has been proposed to be the probable candidate for future NVM applications.