Shin Sang-Yeol, Choi J M, Seo Juhee, Ahn Hyung-Woo, Choi Yong Gyu, Cheong Byung-ki, Lee Suyoun
1] Electronic Materials Research Center, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu. 136-791, Seoul, Republic of Korea [2] Department of Materials Science and Engineering, Korea Aerospace University, Gyeonggi. 412-791, Republic of Korea.
Electronic Materials Research Center, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu. 136-791, Seoul, Republic of Korea.
Sci Rep. 2014 Nov 18;4:7099. doi: 10.1038/srep07099.
The Ovonic Threshold Switch (OTS) based on an amorphous chalcogenide material has attracted much interest as a promising candidate for a high-performance thin-film switching device enabling 3D-stacking of memory devices. In this work, we studied on the electronic structure of amorphous Sb-doped Ge(0.6)Se(0.4) (in atomic mole fraction) film and its characteristics as to OTS devices. From the optical absorption spectroscopy measurement, the band gap (Eg) was found to decrease with increasing Sb content. In addition, as Sb content increased, the activation energy (Ea) for electrical conduction was found to decrease down to about one third of Eg from a half. As to the device characteristics, we found that the threshold switching voltage (Vth) drastically decreased with the Sb content. These results, being accountable in terms of the changes in the bonding configuration of constituent atoms as well as in the electronic structure such as the energy gap and trap states, advance an effective method of compositional adjustment to modulate Vth of an OTS device for various applications.
基于非晶硫族化物材料的双向阈值开关（OTS）作为一种有望用于实现存储器件3D堆叠的高性能薄膜开关器件的候选材料，已引起了广泛关注。在这项工作中，我们研究了非晶态掺锑Ge(0.6)Se(0.4)（原子摩尔分数）薄膜的电子结构及其作为OTS器件的特性。通过光吸收光谱测量发现，带隙（Eg）随锑含量的增加而减小。此外，随着锑含量的增加，导电激活能（Ea）从Eg的一半下降到约三分之一。关于器件特性，我们发现阈值开关电压（Vth）随锑含量急剧下降。这些结果可以通过组成原子的键合构型变化以及能隙和陷阱态等电子结构变化来解释，为通过成分调整来调制用于各种应用的OTS器件的Vth提出了一种有效方法。
