Improved the voltage hysteresis window and endurance in NbOx threshold device by Ti doping

• Published in: Vacuum 2024-04, Vol.222, p.113039, Article 113039
• Main Authors: Chen, Ao, Ma, Guokun, Xiong, Rui, Wang, Hao, Liu, Qiming
• Format: Article
• Language: English
• Subjects: Artificial neuron; Endurance; Margin; NbOx threshold device; Ti doping
• ISSN: 0042-207X; 1879-2715
• DOI: 10.1016/j.vacuum.2024.113039

The artificial neuron based on the NbOx threshold device has exhibited great potential for the hardware implementation of neural networks. Improving the margin of frequency tunability and endurance contributes to expanding its application scenarios effectively. In this work, we prepare NbOx films with different Ti doping contents by magnetron sputtering, and the low concentration of Ti-doped device demonstrates high performance with a sufficient and reliable voltage hysteresis window. Due to the small amount of Ti doping, the Nb–Nb bonding robustness is enhanced and the oxygen vacancy formation energy is reduced, as confirmed by the first principles calculations. The former facilitates broadening the voltage hysteresis window and the latter improves the endurance. Furthermore, the margin of the neuron achieved with this device is improved experimentally. This work confirms a promising approach to designing specialized neurons, advancing the development of full memristive neural networks. •The NbOx: Ti films are prepared by magnetron sputtering and characterized by XPS and TEM solidly.•The voltage hysteresis window and endurance are improved by Ti doping, confirming by first principles calculations.•The Ti-doped neuron performs a broad and reliable margin of frequency tunability.