Binary B-Te Selectors Reinvented: Confined Conductive Paths Unlock Superior Ovonic Threshold Switching

While Te-based ovonic threshold switching (OTS) materials offer advantages such as low-voltage operation and fast switching speed, their relatively low crystallization temperature compared to S- or Se-based counterparts results in poor thermal stability and limited electrical endurance. Various strategies, including element doping and complex composition design, have been explored to address these limitations. In this study, the OTS device properties of B_xTe thin films, a simple two-component system, were systematically investigated across a wide range of compositions. Electrical measurements, band structure analysis, and bonding configuration studies revealed that increasing the boron content enhanced the insulating properties in the off-state and improved the thermal stability of the films. Through composition optimization, B_xTe devices exhibited significantly lower off-current densities while maintaining excellent switching characteristics, outperforming previously reported Te-based OTS materials. Furthermore, detailed analysis confirmed that the unique bonding configurations and structural features associated with boron incorporation play a critical role in achieving the outperformances in B_xTe devices.