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The memory characteristics of Ni-NiOx core-shell nanocrystals (NCs) in the metal-oxide-semiconductor (MOS) capacitor structure were investigated. Scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM) confirm the formation of the spherically shaped, well isolated, and uniformly distributed Ni NCs surrounded by NiOx (~1nm) in SiO2 gate oxide. The Ni-NiOx NCs embedded in SiO2 exhibited a large memory window of 9.8 V as well as efficient programming/erasing speed and improved retention characteristics of about 10 years. A possible band model needed for injection efficiency of carriers was given by considering the electron/hole barrier width and the additional interface states through the NiOx shell layer.

Er2O3 films with good crystallinity have been achieved on an oxidized Si (111) surface by molecule beam epitaxy. The initial growth of Er2O3 films epitaxially grown on Si surfaces is investigated by in situ reflection high energy electron diffraction. An interface layer was formed at the very beginning of the growth of Er2O3 film on Si, which is supposed to be attributed to the Er atom catalytic oxidation effect. The results obtained indicate that with the film growth process continued, oxygen deficient Er oxide captures oxygen from the interface layer which is formed inevitably at the initial growth of Er2O3 film and thus reduce and even remove the interface layer if the condition of O2 pressure is insufficient at a high substrate temperature such as 700℃ in our case.

Reflectance design and synthesis for Er2O3 single layer and Er2O3/TiO2 double layer are made. The optimum reflectance and thickness are determined. The developed simulator can be used for the optimization of antireflecting coatings for optoelectronic devices to improve the power output parameters.