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Published on: May 13, 2020
Evaluating Ovonic Threshold Switching Materials with Topological Constraint Theory
John C Read1, Derek A Stewart1, James W Reiner1
1Western Digital Corporation, 5601 Great Oaks Pkwy, San Jose, California 95119, United States.
Abstract:
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.
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