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Subject: Yttrium oxide ×

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Now showing 1 - 3 of 3
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    Enhanced thermal stability of yttrium oxide-based RRAM devices with inhomogeneous Schottky-barrier
    (Melville, NY : American Inst. of Physics, 2020) Piros, Eszter; Petzold, Stefan; Zintler, Alexander; Kaiser, Nico; Vogel, Tobias; Eilhardt, Robert; Wenger, Christian; Molina-Luna, Leopoldo; Alff, Lambert
    This work addresses the thermal stability of bipolar resistive switching in yttrium oxide-based resistive random access memory revealed through the temperature dependence of the DC switching behavior. The operation voltages, current levels, and charge transport mechanisms are investigated at 25 °C, 85 °C, and 125 °C, and show overall good temperature immunity. The set and reset voltages, as well as the device resistance in both the high and low resistive states, are found to scale inversely with increasing temperatures. The Schottky-barrier height was observed to increase from approximately 1.02 eV at 25 °C to approximately 1.35 eV at 125 °C, an uncommon behavior explained by interface phenomena. © 2020 Author(s).
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    Role of Oxygen Defects in Conductive-Filament Formation in Y2O3-Based Analog RRAM Devices as Revealed by Fluctuation Spectroscopy
    (College Park, Md. [u.a.] : American Physical Society, 2020) Piros, Eszter; Lonsky, Martin; Petzold, Stefan; Zintler, Alexander; Sharath, S.U.; Vogel, Tobias; Kaiser, Nico; Eilhardt, Robert; Molina-Luna, Leopoldo; Wenger, Christian; Müller, Jens; Alff, Lambert
    Low-frequency noise in Y2O3-based resistive random-access memory devices with analog switching is studied at intermediate resistive states and as a function of dc cycling. A universal 1/fα-type behavior is found, with a frequency exponent of α≈1.2 that is independent of the applied reset voltage or the device resistance and is attributed to the intrinsic abundance of oxygen vacancies unique to the structure of yttria. Remarkably, the noise magnitude in the high resistive state systematically decreases through dc training. This effect is attributed to the stabilization of the conductive filament via the consumption of oxygen vacancies, thus reducing the number of active fluctuators in the vicinity of the filament.
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    Spectroscopy of solid-solution transparent sesquioxide laser ceramic Tm:LuYO3
    (Washington, DC : OSA, 2022) Eremeev, Kirill; Loiko, Pavel; Braud, Alain; Camy, Patrice; Zhang, Jian; Xu, Xiaodong; Zhao, Yongguang; Liu, Peng; Balabanov, Stanislav; Dunina, Elena; Kornienko, Alexey; Fomicheva, Liudmila; Mateos, Xavier; Griebner, Uwe; Petrov, Valentin; Wang, Li; Chen, Weidong
    We report on a detailed spectroscopic study of a Tm3+-doped transparent sesquioxide ceramic based on a solid-solution (lutetia – yttria, LuYO3) composition. The ceramic was fabricated using commercial oxide powders by hot isostatic pressing at 1600°C for 3 h at 190 MPa argon pressure. The most intense Raman peak in Tm:LuYO3 at 385.4 cm−1 takes an intermediate position between those for the parent compounds and is notably broadened (linewidth: 12.8 cm−1). The transition intensities of Tm3+ ions were calculated using the Judd-Ofelt theory; the intensity parameters are W2 = 2.537, W4 = 1.156 and W6 = 0.939 [1020 cm2]. For the 3F4 → 3H6 transition, the stimulated-emission cross-section amounts to 0.27 × 10−20 cm2 at 2059nm and the reabsorption-free luminescence lifetime is 3.47 ms (the 3F4 radiative lifetime is 3.85 ± 0.1 ms). The Tm3+ ions in the ceramic exhibit long-wave multiphonon-assisted emission extending up to at least 2.35 µm; a phonon sideband at 2.23 µm is observed and explained by coupling between electronic transitions and the dominant Raman mode of the sesquioxides. Low temperature (12 K) spectroscopy reveals a significant inhomogeneous spectral broadening confirming formation of a substitutional solid-solution. The mixed ceramic is promising for ultrashort pulse generation at >2 µm.