Theoretical insight of confinement of filament in SrMoO3 electrode by compositional control for memory devices

Abstract

This study comprehensively examined the structural, dynamical, electronic, and optical characteristics of SrMoO3 as an electrode material for the confining conducting filament in resistive random access memory (RRAM). This study is novel in that it examines the compositional control and interaction between extrinsic defects (dopants) and intrinsic defects (oxygen vacancies) acting as a transition driving force in thermodynamically stable composites for a resistive switching mechanism. In the absence of oxygen vacancies (Vos), relatively strong, confined metal-cation-based filaments formed around the dopant proved that extrinsic defects caused by substitutional dopants replacing Mo atoms are more efficient at producing low-resistance states in SrMoO3 than intrinsic defects. Filaments of the order of a few Ås around the defect site will help to solve the uniformity and scaling problems associated with resistive switching. This finding further supported the usefulness of noise (in this case, a dopant or Vos is the source of an external or internal perturbation). The optical conductivity produced in response to incident photons in the infrared energy range also verified the suitability of doped SrMoO3 systems for optoelectronic RRAM synaptic devices. This study's potential energy lineup-based dopant selection rule suggested that substitutional doping using the heavy transition metal Hf as an acceptor dopant yields relatively excellent results for applications involving low-power SrMoO3-based RRAM synaptic devices.