Electrode-Modulated oxygen defect profiles in intentionally oxidized chalcogenide ovonic threshold switch selectors
Year: 2026
Type: article
Abstract: For next-generation memory technologies, crossbar selector devices play a critical role in suppressing sneak-path currents and enabling three-dimensional integration. This study investigates the operation of ovonic threshold switch based on Se-alloyed TeOx, focusing on how interfacial oxidation and electrode materials influence the switching behavior. A small amount of oxygen was intentionally incorporated during the deposition step, enabling stable selector operation without the need for additional dopants. Devices fabricated with Pt, W, and Cr electrodes exhibited threshold switching with sub-50 ns responses and selectivity exceeding 103, with Pt delivering the best endurance (>103 cycles). In contrast, Ti, Ni, and Al electrodes formed interfacial oxide layers, as confirmed by cross-sectional transmission electron microscopy, energy-dispersive X-ray spectroscopy, and electron energy loss spectroscopy, leading to resistive random-access memory-like behavior or switching failures. Optimal performance was consistently observed at a specific Se sputtering power (10 W), corresponding to low areal density and improved film uniformity, as verified by X-ray photoelectron spectroscopy, Rutherford backscattering spectrometry, atomic force microscopy, and Raman spectroscopy. These findings demonstrate that selector capabilities are governed not only by the active-layer composition but also by electrode-induced interfacial defects. This work offers concrete design guidelines for reliable, low-voltage selector integration in high-density memory architectures.
Source: Applied Surface Science
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,930
Awards: G3290696572, G644350153, G6456595263
OpenAlex ID: W7140028540