Forming-Free Selectors Based on Te in an Insulating SiO x Matrix

• Published in: IEEE transactions on electron devices Vol. 71; no. 1; pp. 530 - 535
• Main Authors: Datye, Isha M., Vaziri, Sam, Ambrosi, Elia, Khan, Asir Intisar, Kwon, Heungdong, Wu, Cheng-Hsien, Hsu, Chen-Feng, Guy, Jeremy, Lee, Tung-Ying, Wong, H.-S. Philip, Bao, Xinyu
• Format: Journal Article
• Language: English
• Published: New York The Institute of Electrical and Electronics Engineers, Inc. (IEEE) 01-01-2024
• Subjects: Low voltage; Selectors; Temperature dependence; Threshold voltage
• ISSN: 0018-9383; 1557-9646
• DOI: 10.1109/TED.2023.3336629

Low voltage and low OFF-current selectors are needed to meet the requirements for cross-point array architectures in embedded memories. Chalcogenide-based selectors have been widely studied for such applications, but no single material system has yet demonstrated all the specifications required for integration with nonvolatile memory. This article presents arsenic-free selectors based on a simple and stable material system consisting of Te in an insulating SiOx matrix. By modifying the thickness and atomic composition of films, tunable switching voltage and OFF-current are achieved. Optimized forming-free SiOxTey selectors are demonstrated with a threshold voltage of ~1.2 V and an OFF-current of ~3 nA at 0.5 V. Size- and temperature-dependent measurements provide insight into the different conduction mechanisms of devices with different forming behaviors. Threshold voltage drift of ~30 mV/decade is measured for both forming-required and forming-free devices. These selectors maintain their functionality after a 300°C anneal and a recovery pulse, and they are stable after one year stored in air. Excellent endurance of 1011 cycles is reported, making these devices promising for integration with nonvolatile memory.