Meng Jingjia, Goodwill Jonathan M, Strelcov Evgheni, Bao Kefei, McClelland Jabez J, Skowronski Marek
Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States.
Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States.
ACS Appl Electron Mater. 2023 Apr 10;5(4):2414-2421. doi: 10.1021/acsaelm.3c00229. eCollection 2023 Apr 25.
Understanding the physical changes during electroformation and switching processes in transition-metal-oxide-based non-volatile memory devices is important for advancing this technology. Relatively few characteristics of these devices have been assessed in operando. In this work, we present scanning thermal microscopy measurements in vacuum on TaO -based memory devices electroformed in both positive and negative polarities and high- and low-resistance states. The observed surface temperature footprints of the filament showed higher peak temperatures and narrower temperature distributions when the top electrode served as the anode in the electroformation process. This is consistent with a model in which a hot spot is created by a gap in the conducting filament that forms closest to the anode. A similar behavior was seen on comparing the high-resistance state to the low-resistance state, with the low-resistance footprint showing a lower peak and a larger width, consistent with the gap disappearing when the device is switched from high resistance to low resistance.
了解基于过渡金属氧化物的非易失性存储器件在电形成和切换过程中的物理变化对于推动该技术发展至关重要。目前对这些器件的相关特性进行原位评估的还相对较少。在这项工作中，我们展示了在真空中对基于TaO的存储器件进行扫描热显微镜测量，这些器件在正负极性以及高阻和低阻状态下均进行了电形成。当顶部电极在电形成过程中作为阳极时，观察到的丝状结构的表面温度特征显示出更高的峰值温度和更窄的温度分布。这与一个模型相符，即在最靠近阳极处形成的导电细丝中的间隙会产生一个热点。在比较高阻态和低阻态时也观察到了类似的行为，低阻态的温度特征显示出较低的峰值和较宽的宽度，这与器件从高阻切换到低阻时间隙消失的情况一致。
