Zrinski Ivana, Mardare Cezarina Cela, Jinga Luiza-Izabela, Kollender Jan Philipp, Socol Gabriel, Minenkov Alexey, Hassel Achim Walter, Mardare Andrei Ionut
Institute of Chemical Technology of Inorganic Materials, Johannes Kepler University Linz, Altenberger Str. 69, 4040 Linz, Austria.
Danube Private University, Steiner Landstrasse 124, 3500 Krems-Stein, Austria.
Nanomaterials (Basel). 2021 Mar 8;11(3):666. doi: 10.3390/nano11030666.
Anodic HfO memristors grown in phosphate, borate, or citrate electrolytes and formed on sputtered Hf with Pt top electrodes are characterized at fundamental and device levels. The incorporation of electrolyte species deep into anodic memristors concomitant with HfO crystalline structure conservation is demonstrated by elemental analysis and atomic scale imaging. Upon electroforming, retention and endurance tests are performed on memristors. The use of borate results in the weakest memristive performance while the citrate demonstrates clear superior memristive properties with multilevel switching capabilities and high read/write cycling in the range of 10. Low temperature heating applied to memristors shows a direct influence on their behavior mainly due to surface release of water. Citrate-based memristors show remarkable properties independent on device operation temperatures up to 100 °C. The switching dynamic of anodic HfO memristors is discussed by analyzing high resolution transmission electron microscope images. Full and partial conductive filaments are visualized, and apart from their modeling, a concurrency of filaments is additionally observed. This is responsible for the multilevel switching mechanism in HfO and is related to device failure mechanisms.
对在磷酸盐、硼酸盐或柠檬酸盐电解质中生长，并在溅射的铪上形成铂顶电极的阳极氧化铪基忆阻器进行了基础和器件层面的表征。通过元素分析和原子尺度成像证明，在保持HfO晶体结构的同时，电解质物种深入到阳极忆阻器中。在电形成后，对忆阻器进行了保持和耐久性测试。使用硼酸盐时忆阻性能最弱，而柠檬酸盐则表现出明显优越的忆阻特性，具有多级开关能力，且在10的范围内具有高读写循环次数。对忆阻器施加低温加热主要由于水的表面释放而对其行为产生直接影响。基于柠檬酸盐的忆阻器在高达100°C的器件工作温度下表现出显著特性，与器件操作温度无关。通过分析高分辨率透射电子显微镜图像讨论了阳极氧化铪基忆阻器的开关动力学。观察到了完整和部分导电细丝，除了对它们进行建模外，还额外观察到细丝的并发情况。这是HfO中多级开关机制的原因，并且与器件失效机制有关。
