Enhancing Se-based Selector-only Memory with Ultra-fast Write Speed (~ 10 ns) and Superior Retention Characteristics (> 10 years at RT) via Material Design and UV Treatment Engineering

We investigate the effect of material design and UV treatment on nanoscale (d = 50 nm) ovonic threshold switch (OTS) devices for selector-only memory (SOM) applications. By characterizing OTS devices with varying material compositions, we identified selenium (Se) as a key element for SOM operation. The optimized OTS device exhibited a large memory window (MW > 1.2 V) with an ultra-fast write operation speed (~ 10 ns). Additionally, we demonstrate that interface engineering with proper UV treatment significantly improved device variability characteristics. UV-treated OTS devices demonstrated excellent retention (> 10 years at RT) and cycling endurance properties (> 10 ⁸ cycles). Analysis of Raman and XPS spectra revealed that SOM properties were determined by the bonding nature associated with the Se element.