Electronic threshold switching of As-embedded SiO₂ selectors: charged oxygen vacancy model

Sneak current issues in crossbar arrays of non-volatile memories can be effectively alleviated using threshold switching (TS)-based selectors. However, 1-selector–1-resistor integration requires coherence between the constituent materials and operational parameters of the two components. Here, we propose a highly coherent selector via in-depth investigation of the operation process of a fab-friendly As-SiO₂ selector unit. The structural and electrical characteristics of an As-embedded SiO₂ selector are analyzed, and the TS-on and -off operational mechanism is presented. Further, the critical control elements governing the selector operation are identified, including the electron charging into the oxygen vacancies in the SiO₂ matrix and energy band alignment between the As cluster and charged oxygen vacancies in SiO₂. Consequently, practical control strategies for the TS behavior are proposed with a pulse scheme applicable to actual device operation. The proposed TS operational mechanism and analytical methodology can contribute to interpreting and integrating various memory/selector components, thereby advancing their operational and integrative research.