The Experts below are selected from a list of 264 Experts worldwide ranked by ideXlab platform

Tsutomu Suzuki - One of the best experts on this subject based on the ideXlab platform.

A. Subrahmanyam - One of the best experts on this subject based on the ideXlab platform.

  • Studies on the correlation between electrochromic colouration and the relative Density of tungsten trioxide (WO3−x) thin Films prepared by electron beam evaporation
    Journal of Physics D: Applied Physics, 2009
    Co-Authors: K. Muthu Karuppasamy, A. Subrahmanyam
    Abstract:

    The colouration efficiency in the electrochromic devices depends upon the amount of intercalating charge in the tungsten oxide (WO3−x) thin Films. One of the physical properties of the Film that significantly influence the intercalating charge is the Film Density. In this paper, the dependence of intercalated charge in WO3−x thin Films on the Film Density is reported. The amorphous tungsten oxide thin Films have been prepared by electron beam evaporation at three substrate temperatures: 300, 470 and 570 K. With increasing substrate temperature, the refractive indices of the Films increase. The relative Film Density calculated from the refractive index using the Lorentz–Lorentz relationship increases with the substrate temperature. With increasing Density of the WO3 thin Films, the diffusion coefficients of protons and the amount of intercalated charge decrease. The intercalated charge in the coloured electrochromic thin Films brings about a change in the surface work function of the thin Film; the difference in the surface work function (between the coloured and the bleached states) is measured by the Kelvin probe. In the present investigation, an intercalating charge of 59, 48 and 39 mC cm−2 brings about a change of 0.24, 0.16 and 0.13 eV in the surface work function of the WO3 thin Films.

Masakazu Aono - One of the best experts on this subject based on the ideXlab platform.

  • redox reactions at cu ag ta2o5 interfaces and the effects of ta2o5 Film Density on the forming process in atomic switch structures
    Advanced Functional Materials, 2015
    Co-Authors: Tohru Tsuruoka, Ilia Valov, Stefan Tappertzhofen, Jan Van Den Hurk, Tsuyoshi Hasegawa, Rainer Waser, Masakazu Aono
    Abstract:

    Cu and Ag redox reactions at the interfaces with Ta2O5 and the impact of Ta2O5 Film Density on the forming process of Cu,Ag/Ta2O5/Pt atomic switch structures are investigated. Cyclic voltammetry measurements revealed that under positive bias to the Cu (Ag) electrode, Cu is preferentially oxidized to Cu2+, while Ag is oxidized to Ag+ ions. Subsequent negative bias causes a reduction of oxidized Cu (Ag) ions at the interfaces. The diffusion coefficient of the Cu and Ag ions in the Ta2O5 Film is estimated from the results from different bias voltage sweep rates. It is also found that the redox current is enhanced and the forming voltage of the Cu/Ta2O5/Pt cell is reduced when the Density of the Ta2O5 Film is decreased. This result indicates the importance of the structural properties of the matrix oxide Film in understanding and controlling resistive switching behavior.

Miin-jang Chen - One of the best experts on this subject based on the ideXlab platform.

  • Dielectric properties and reliability enhancement of atomic layer deposited thin Films by in situ atomic layer substrate biasing
    Journal of Materials Chemistry C, 2020
    Co-Authors: Chun-yi Chou, Teng-jan Chang, Chin-i. Wang, Chun-yuan Wang, Yu-tung Yin, Tsai-fu Chung, Jer-ren Yang, Hsin-chih Lin, Miin-jang Chen
    Abstract:

    A novel “atomic layer substrate biasing (ALSB)” technique is proposed to improve the dielectric properties including Film Density, dielectric constant (K), and leakage current Density (Jg) and the reliability of nanoscale thin Films. In the ALSB process, in situ Ar plasma generated by substrate biasing is layer-by-layer introduced into each cycle of atomic layer deposition. Energy delivery from the plasma toward the as-deposited layer boosts the migration of adatoms, leading to ∼10% increase of the Film Density, ∼3-order-of-magnitude reduction of Jg, and an increment of K being as large as 40.7 of a ZrO2 layer of ∼5 nm. The reliability enhancement upon the ALSB treatment is demonstrated by constant-voltage-stress (CVS) and the time-dependent-dielectric-breakdown (TDDB) tests, which confirm the suppression of stress-induced traps and a high electric field of 4.7 MV cm−1 projected for a 10 year lifetime. Significant improvements in the Film Density, Jg, K, and the reliability indicate that ALSB is a highly effective technique to modify the quality of ALD-deposited thin Films, which can be widely used in a variety of fields including energy saving, green energy, nanoelectronics, and biomedical applications.

Rainer Waser - One of the best experts on this subject based on the ideXlab platform.

  • redox reactions at cu ag ta2o5 interfaces and the effects of ta2o5 Film Density on the forming process in atomic switch structures
    Advanced Functional Materials, 2015
    Co-Authors: Tohru Tsuruoka, Ilia Valov, Stefan Tappertzhofen, Jan Van Den Hurk, Tsuyoshi Hasegawa, Rainer Waser, Masakazu Aono
    Abstract:

    Cu and Ag redox reactions at the interfaces with Ta2O5 and the impact of Ta2O5 Film Density on the forming process of Cu,Ag/Ta2O5/Pt atomic switch structures are investigated. Cyclic voltammetry measurements revealed that under positive bias to the Cu (Ag) electrode, Cu is preferentially oxidized to Cu2+, while Ag is oxidized to Ag+ ions. Subsequent negative bias causes a reduction of oxidized Cu (Ag) ions at the interfaces. The diffusion coefficient of the Cu and Ag ions in the Ta2O5 Film is estimated from the results from different bias voltage sweep rates. It is also found that the redox current is enhanced and the forming voltage of the Cu/Ta2O5/Pt cell is reduced when the Density of the Ta2O5 Film is decreased. This result indicates the importance of the structural properties of the matrix oxide Film in understanding and controlling resistive switching behavior.