Advanced Research Laboratories (ARL)

Permanent URI for this communityhttps://hdl.handle.net/11693/115562

Browse

Browsing Advanced Research Laboratories (ARL) by Subject "Annealing"

Filter results by typing the first few letters
Now showing 1 - 2 of 2
  • Thumbnail Image
    ItemOpen Access
    Comparison of electron and hole charge-discharge dynamics in germanium nanocrystal flash memories
    (AIP Publishing, 2008-02) Akça, İmran B.; Dâna, Aykutlu; Aydınlı, Atilla; Turan, R.
    Electron and hole charge and discharge dynamics are studied on plasma enhanced chemical vapor deposition grown metal-oxide-silicon germanium nanocrystal flash memory devices. Electron and hole charge and discharge currents are observed to differ significantly and depend on annealing conditions chosen for the formation of nanocrystals. At low annealing temperatures, holes are seen to charge slower but to escape faster than electrons. They discharge slower than electrons when annealing temperatures are raised. The results suggest that discharge currents are dominated by the interface layer acting as a quantum well for holes and by direct tunneling for elec-trons.
  • Thumbnail Image
    ItemOpen Access
    Growth and characterization of nanocrystalline SrTiOx films: room temperature deposition using RF sputtering system in a pure argon environment
    (Institute of Physics Publishing, 2017-05) Bayrak, Türkan; Goldenberg, Eda
    We report a comprehensive description of the structure, optical and electrical properties of asdeposited and annealed SrTiOx (STO) thin films. Nanocrystalline STO films were deposited on p-type Si (1 0 0) and UV-grade fused silica substrates by RF magnetron sputtering at room temperature in a pure argon environment. Well adhered and transparent films with very smooth surfaces were obtained. As-deposited films showed 70% transparency in the visible spectrum, transparency increased to 77% after annealing at 700 °C. The direct and indirect optical band gaps were found to be 2.88 eV and 2.44 eV, for as-deposited films. For annealed films, indirect band gap increased to 2.57 eV while the direct optical band gap value remained constant. Upon annealing, the refractive indices (n) of the films decreased from 2.36 to 2.32. Ag/STO/p-Si device structures were also fabricated and characterized by current-voltage, capacitance-voltage and dielectric measurements. The calculated values are compared with experimental data from the literature and discussed in terms of device performances. A butterfly loop-type hysteresis curve was observed for the voltage-dependent capacitance measurement in annealed thin film devices. Dielectric constants were calculated as 31.7 and 57.4 for as-deposited and annealed films at 100 kHz, respectively. Charge storage capacity was found to be >4.5 μC cm-2 for as-deposited and 3.5 μC cm-2 for annealed films.