The ovonic threshold switching characteristics in SixTe1−x based selector devices.

In this study, SixTe1−x-based selector devices with outstanding performance were fabricated by standard CMOS technology. The ovonic threshold switching characteristics and the apparent threshold voltage Vth were observed in I-V curves. The increase of Si content directly induced the decrease of leakage current of the W/SixTe1−x/W devices. It was found that the leakage current of the W/SixTe1−x/W devices decreased with the increase of the thickness of SixTe1−x films. An optimized bidirectional selector was achieved by modulating the composition and thickness of SixTe1−x films. The SixTe1−x-based selector device has a series of advantages, such as ultrahigh selectivity (~ 107), proper operating current (100 µA), threshold voltage (~ ± 1.2 V), as well as satisfactory switching uniformity and retention performance. Corresponding Poole-Frenkel based analytical model and energy band model were employed to explain the conduction mechanism and threshold switching characteristics of W/SixTe1−x/W selector devices. The origin of the threshold switching characteristics is considered to be that the high electric field derived carriers to tunnel from the deep traps to the shallow traps when a high bias was applied to the devices. [ABSTRACT FROM AUTHOR]