Impacts to FeRAM design arising from interfacial dielectric layers and wake up modulation in ferroelectric hafnium zirconium oxide

• Published in: IEEE transactions on ultrasonics, ferroelectrics, and frequency control Vol. 71; no. 2; p. 1
• Main Authors: Henry, M. David, Smith, Sean W., Fields, Shelby S., Jaszewski, Samantha T., Esteves, Giovanni, Heinrich, Helge, Ihlefeld, Jon F.
• Format: Journal Article
• Language: English
• Published: United States IEEE 01.02.2024; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Aluminum; Aluminum oxide; Circuits; Cycles; Depolarization; Dielectrics; Electric potential; Electrodes; Endurance; ferroelectric capacitors; Ferroelectric films; Ferroelectric materials; Ferroelectricity; Hafnium; Hf0.5Zr0.5O2 (HZO); Hf<sub xmlns:ali="http://www.niso.org/schemas/ali/1.0/" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">0.5 Zr<sub xmlns:ali="http://www.niso.org/schemas/ali/1.0/" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">0.5 O<sub xmlns:ali="http://www.niso.org/schemas/ali/1.0/" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">2 (HZO); metal-ferroelectric-metal (MFM) capacitor; niobium; Niobium nitride; Nonvolatile memory; Performance evaluation; Random access memory; Rapid thermal annealing; Voltage; wake-up; Zirconium oxides
• DOI: 10.1109/TUFFC.2023.3311328
• ISSN: 0885-3010

As ferroelectric hafnium zirconium oxide (HZO) becomes more widely utilized in ferroelectric microelectronics, integration impacts of intentional and nonintentional dielectric interfaces and their effects upon the ferroelectric film wake up and circuit parameters become important to understand. In this work, the effect of the addition of a linear dielectric aluminum oxide, Al 2 O 3 , below a ferroelectric Hf 0.58 Zr 0.42 O 2 film in a capacitor structure for FeRAM applications with NbN electrodes was measured. Depolarization fields resulting from the linear dielectric is observed to induce a reduction of the remanent polarization of the ferroelectric. Addition of the aluminum oxide also impacts the wake up of the HZO with respect to the cycling voltage applied. Intricately linked to the design of a FeRAM 1C/1T cell, the metal-ferroelectric-insulator-metal (MFIM) devices are observed to significantly shift charge related to the read states based on aluminum oxide thickness and wake up cycling voltage. A 33% reduction in the separation of read states is measured, which complicates how a memory cell is designed and illustrates the importance of clean interfaces in devices.