Evaluating Ovonic Threshold Switching Materials with Topological Constraint Theory

The physical properties of ovonic threshold switching (OTS) materials are of great interest due to the use of OTS materials as selectors in cross-point array nonvolatile memory systems. Here, we show that the topological constraint theory (TCT) of chalcogenide glasses provides a robust framework to describe the physical properties of sputtered thin film OTS materials and electronic devices. Using the mean coordination number (MCN) of an OTS alloy as a comparative metric, we show that changes in data trends from several measurements are signatures of the transition from a floppy to a rigid glass network as described by TCT. This approach provides a means to optimize OTS selector materials for device applications using film-level measurements.