Structure effects on resistive switching of Al/TiOx/Al devices for RRAM applications

Abstract

Resistive switching characteristics are investigated for Al/TiOx/Al devices, particularly for the structural effects in crossbar and via-hole-type devices. The via-hole structure shows more reliable switching characteristics than the crossbar structure, owing to the elimination of possible edge effects. The asymmetric switching behavior is analyzed with top Al/TiOx and bottom Al/TiOx interfaces. A trap-controlled space-charge-limited-current model is proposed as a possible switching mechanism, and it is verified that switching mainly occurs on the top electrode/TiOx interface side.