Metal-HfO2-Ge capacitor: Its enhanced charge trapping properties with S-treated substrate and atomic-layer-deposited HfO2 layer

Abstract

The charge trapping properties of metal-HfO2-Ge capacitor as a nonvolatile memory have been investigated with (NH4)(2)S-treated Ge substrate and atomic-layer-deposited HfO2 layer. The interfacial layer generated by (NH4)(2)S-treated Ge substrate reveals a trace of -S- bonding, very sharp interface edges, and smooth surface morphology. The Ru-HfO2-Ge capacitor with (NH4)(2)S-treated Ge substrate shows an enhanced interface state with little frequency dispersion, a lower leakage current, and very reliable properties with the enhanced endurance and retention than Ru-HfO2-Ge capacitor with cyclic-cleaned Ge substrate.