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    InChaP: A simple software for computation of charged particle interaction parameters
    (Korean Nuclear Soc, 2025) Cici, Ali; Morkoc, Berk; Dag, Hueseyin; Aydinbakar, Levent; Sayyed, M. I.; Buyukyildiz, Mehmet
    A new, user-friendly software called Interaction of Charged Particle has been developed to simulate ion interactions across various applications. Designed with robust physical formulations and computational techniques using Python packages, InChaP operates within a broad energy range of 0.01-1000 MeV. InChaP calculates mass stopping power, stopping cross-section, relative stopping power, effective atomic number, and electron density for any chemical compound or composite using a logarithmic interpolation procedure across a wide range of ion energies. It also generates parameters for a specific ion of energy within the working range, and users can obtain the results in common spreadsheet formats. The software is freely available to all researchers. Good agreements were obtained in the effective atomic number between InChaP and some possible results from literature. These agreements were diff.% <= 11.44 and diff.% <= 1.94 for He ion interaction and for electron interaction in calculation of effective atomic number for spleen at 1 MeV.
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    Post-deposition annealing effect on the structural and electrical properties of Ytterbium oxide as an alternative gate dielectric
    (Elsevier Science Sa, 2022) Morkoc, Berk; Kahraman, Aysegul; Yilmaz, Ercan
    The possibility of ytterbium(III) oxide, one of the rare earth oxides, to replace silicon dioxide used as the gate dielectric is discussed in this article. For such a replacement, it is primarily necessary to understand the physical and chemical characteristics of ytterbium(II) oxide as a candidate, such as bond structure, electronic structure, band offsets with Si, dielectric constant, interfacial states and defect behavior. The effects of structural and electrical features of ytterbium(III) oxide-based MOS capacitors on device performance are investigated. The electron beam physical vapor deposition (EBPVD) technique was used for the deposition of ytterbium(III) oxide thin films. The 122 nm thick Yb2O3 thin film was annealed at four different temperatures (200 degrees C, 400 degrees C, 600 degrees C, and 800 degrees C) in nitrogen environment. The crystallite size determined from the as-deposited sample as 15 nm is the lowest. As expected, crystallite sizes increased as a result of increasing annealing temperature. The presence of Yb2+ oxidation states increased in the region close to the interface or at the interface. The binding energies of the Yb 4d and O 1s spectra increased with increasing depth into the films. In the O 1s spectra, the organic bonds on the surface first decreased and then increased with increasing annealing temperature. Silicate formation at the interface was determined for the annealed samples. This affected the electrical performance of the capacitors. The calculated dielectric values range from 12.1 to 15.8. Interface level densities were found in the order of 10(12) cm(-2) and it did not exhibit frequency-dependent behavior. The calculated values for the effective charge densities varied between -24.19x10(11) - 7.03x10(11) cm(-2). It has been determined that mostly negative charges are trapped more for different capacitors. Finally, Fermi energy level, dopant concentration, diffusion potential and barrier heights were calculated.
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    The relationship between structural and electrical properties of the post-deposition annealed Er2O3/n-Si hetero-structures
    (Elsevier Ltd, 2021) Kahraman, Aysegul; Morkoc, Berk; Yilmaz, Ercan
    This study presents comprehensive results on the structural modifications of Er2O3/n-Si hetero-structures under post-deposition annealing (PDA) and the effects of these changes on the electrical characteristics of the Al/Er2O3/n-Si/Al MOS capacitors. The Er2O3 films were grown on n-Si substrate with RF magnetron sputtering and annealed under nitrogen at RT, 300 °C, 500 °C, 600 °C, 700 °C. The increasing grain size of the films up to 300 °C did not show a significant change in other annealing temperatures. The erbium silicate content in the RT and 600 °C-Er2O3/n-Si interface is quite higher than those of 500 °C and 700 °C, while a silicate-like layer was not found at 300 °C. The highest dielectric constant (ε) value was obtained from the 500 °C-Er2O3 MOS capacitor due to the lowest oxygen deficient bond content. It was found that Qeff values tend to increase as the oxygen concentration decreases in the film. It was determined that Er-Er oxygen deficient bonds may have acted as negative charge trap centers. Although the Er-M content in the 700 °C-Er2O3/n-Si is higher than that of 500 °C, lower Qeff values were obtained from the 700 °C-Er2O3 MOS capacitor due to the higher Si-Si oxygen deficient bond content, which is most likely act as a positive charge trap center. It was concluded that the contributions of oxide trap and interface trap charges should be evaluated together in establishing a link between electrical characteristics and structural analyses.