Nandi Sanjoy Kumar, Puyoo Etienne, Nath Shimul Kanti, Albertini David, Baboux Nicolas, Das Sujan Kumar, Ratcliff Thomas, Elliman Robert G
Department of Electronic Materials Engineering, Research School of Physics, Australian National University, Canberra, Australian Capital Territory 2601, Australia.
Université Lyon, INSA Lyon, CNRS, Ecole Centrale de Lyon, Université Claude Bernard Lyon 1, CPE Lyon, INL, UMR5270, 69621 Villeurbanne, France.
ACS Appl Mater Interfaces. 2022 Jun 29;14(25):29025-29031. doi: 10.1021/acsami.2c06870. Epub 2022 Jun 14.
Temperature mapping by in situ thermoreflectance thermal imaging (TRTI) or midwave infrared spectroscopy has played an important role in understanding the origins of threshold switching and the effect of insulator-metal transitions in oxide-based memrsitive devices. In this study, we use scanning thermal microscopy (SThM) as an alternative thermal mapping technique that offers high spatial resolution imaging (∼100 nm) and is independent of material. Specifically, SThM is used to map the temperature distribution in NbO-based cross-bar and nanovia devices with Pt top electrodes. The measurements on cross-bar devices reproduce the current redistribution and confinement processes previously observed by TRTI but without the need to coat the electrodes with a material of high thermo-reflectance coefficient (e.g., Au), while those on the nanovia devices highlight the spatial resolution of the technique. The measured temperature distributions are compared with those obtained from physics-based finite-element simulations and suggest that thermal boundary resistance plays an important role in heat transfer between the active device volume and the top electrode.
通过原位热反射热成像（TRTI）或中波红外光谱进行温度映射，在理解阈值开关的起源以及氧化物基忆阻器件中绝缘体-金属转变的影响方面发挥了重要作用。在本研究中，我们使用扫描热显微镜（SThM）作为一种替代的热映射技术，它提供高空间分辨率成像（约100纳米）且与材料无关。具体而言，SThM用于绘制具有铂顶电极的基于NbO的交叉棒和纳米通孔器件中的温度分布。对交叉棒器件的测量重现了先前TRTI观察到的电流重新分布和限制过程，但无需用高热反射系数的材料（如金）涂覆电极，而对纳米通孔器件的测量突出了该技术的空间分辨率。将测量得到的温度分布与基于物理的有限元模拟结果进行比较，结果表明热边界电阻在有源器件体积与顶电极之间的热传递中起着重要作用。
