Electrolyte-Dependent Modification of Resistive Switching in Anodic Hafnia
Ivana Zrinski,
Cezarina Cela Mardare,
Luiza-Izabela Jinga,
Jan Philipp Kollender,
Gabriel Socol,
Alexey Minenkov,
Achim Walter Hassel,
Andrei Ionut Mardare
Affiliations
Ivana Zrinski
Institute of Chemical Technology of Inorganic Materials, Johannes Kepler University Linz, Altenberger Str. 69, 4040 Linz, Austria
Cezarina Cela Mardare
Institute of Chemical Technology of Inorganic Materials, Johannes Kepler University Linz, Altenberger Str. 69, 4040 Linz, Austria
Luiza-Izabela Jinga
National Institute for Lasers, Plasma and Radiation Physics, Atomistilor Str. 409, 077125 Bucharest-Magurele, Romania
Jan Philipp Kollender
Institute of Chemical Technology of Inorganic Materials, Johannes Kepler University Linz, Altenberger Str. 69, 4040 Linz, Austria
Gabriel Socol
National Institute for Lasers, Plasma and Radiation Physics, Atomistilor Str. 409, 077125 Bucharest-Magurele, Romania
Alexey Minenkov
Christian Doppler Laboratory for Nanoscale Phase Transformations, Center of Surface and Nanoanalytics, Johannes Kepler University Linz, Altenberger Str. 69, 4040 Linz, Austria
Achim Walter Hassel
Institute of Chemical Technology of Inorganic Materials, Johannes Kepler University Linz, Altenberger Str. 69, 4040 Linz, Austria
Andrei Ionut Mardare
Institute of Chemical Technology of Inorganic Materials, Johannes Kepler University Linz, Altenberger Str. 69, 4040 Linz, Austria
Anodic HfO2 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 HfO2 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 106. 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 HfO2 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 HfO2 and is related to device failure mechanisms.
