Defect Engineering of BTe Ovonic Threshold Switch (OTS) With Nitrogen Doping for Improved Electrical and Reliability Performance

This study investigates the effect of N-doping on the nanoscale (d = 30 nm) BTe ovonic threshold switch (OTS) device to achieve ideal selector characteristics in terms of leakage current, cycling endurance, and variation. Based on our findings, N-doping significantly improves device performance. In particular, the N-doped BTe OTS exhibits an ultra-low leakage current (
$\text{I}_{\textit {off}}$
@ 1/2 V
$_{\textit {th}}$
= 750 pA), low threshold voltage (
$\text{V}_{\textit {th}}$
) variation (
$\sigma < 30$
mV), excellent cycling endurance (> 1011), and low
$\text{V}_{\textit {th}}$
drift (
$\gamma $
= 30 mV/dec.) characteristics. From density functional theory (DFT) calculation, we found that an increase in Te-Te lifetime after the N-doping process can improve the reliability characteristics of the OTS device. This study contributes importantly to the development of high-performance OTS devices, providing a fundamental understanding of the role of N-doping in enhancing device properties.