Tuning oxygen vacancies and resistive switching properties in ultra-thin HfO2 RRAM via TiN bottom electrode and interface engineering

• DOI: 10.1016/j.apsusc.2021.149386
• Publication Date: 2021-03-05T21:08:01Z
• Authors: Zhihua Yong; Karl-Magnus Persson; Mamidala Saketh Ram; Giulio D'Acunto; Yi Liu; Sandra Benter; Jisheng Pan; Zheshen Li; Mattias Borg; Anders Mikkelsen; Lars-Erik Wernersson; Rainer Timm
• Keywords: X-ray photoelectron spectroscopy; 0103 physical sciences; Band bending; Resistive switching; 02 engineering and technology; Titanium nitride; 0210 nano-technology; RRAM; 01 natural sciences; 7. Clean energy; Hafnium oxide

Resistive random access memory (RRAM) technologies based on non-volatile resistive filament redox switching oxides have the potential of drastically improving performance future mass-storage solutions. However, physico-chemical properties TiN bottom metal electrode (BME) can significantly alter (RS) behavior oxygen-vacancy RRAM devices, yet correlation between RS and HfOx/TiN interface remains unclear. Here, we establish this particular via detailed material electrical characterization for purpose achieving further enhancement stack integration. Two types stacks were fabricated where BME was by physical vapor deposition (PVD) atomic layer (ALD), respectively. The HfOx in HfOx/PVD-TiN is more oxygen deficient than that HfOx/ALD-TiN because defective PVD-TiN probably pristine ALD-TiN has a thicker TiO2 overlayer. Higher concentration vacancies induces larger magnitude band bending at leads to formation higher Schottky barrier. Pulsed endurance measurements up 106 switches, with 10 μA ± 1.0 V pulses, demonstrate studied ultra-thin-HfOx/TiN device dense, large scale, low-power