Interaction between forming pulse and integration process flow in ePCM

Abstract

Ge enrichment of the GeSbTe (GST) chalcogenide made possible for embedded phase change memories (ePCM) to guarantee the retention level necessary to satisfy the automotive market’s requirements. In Ge-GST devices at the end of the fabrication process memory cells are in the pristine state (virgin) and, in order to be programmed, an activation step is necessary (forming). In this work an investigation on the influence of two back end of the line (BEOL) processes on the virgin state and forming process is presented. A model that accurately replicates both physical and electrical trends is also shown.