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Presents a study which investigated the Si[sub1-subx]Ge[subx]/Si strained-layer superlattices grown by molecular beam epitaxy on silicon substrates by x-ray double crystal diffraction and x-ray grazing incidence diffraction. Components of the superlattices; Discussion on lattice relaxation; Results of double-crystal diffraction.

Ultrathin amorphous Ni–Ti film is investigated as conductive diffusion barrier layer to integrate La0.5Sr0.5CoO3/PbZr0.4Ti0.6O3/La0.5Sr0.5CoO3 (LSCO/PZT/LSCO) capacitors on silicon. X-ray photoelectron spectroscopy results demonstrate that Ni in LSCO/Ni–Ti/Si heterostructure is not oxidized after 550 °C annealing in oxygen. The structural properties of LSCO/PZT/LSCO/Ni–Ti/Si are characterized by x-ray diffraction and transmission electron microscopy. It is found that Ni–Ti film is still amorphous and that there are no discernible reactions at the interfaces of the sample. LSCO/PZT/LSCO capacitor, measured at 5 V, possesses very good ferroelectric properties, such as low coercive field (∼1.28 V), high remnant polarization (∼27.9 μC/cm2), and good fatigue-free characteristic, implying that ultrathin amorphous Ni–Ti film can be used as barrier layer for fabricating high-density ferroelectric random access memories. [ABSTRACT FROM AUTHOR]

We report on the use of amorphous Ni–Al film (a-Ni–Al) as conductive diffusion barrier layer to integrate La0.5Sr0.5CoO3/PbZr0.4Ti0.6O3/La0.5Sr0.5CoO3 capacitors on silicon. Cross-sectional observation by transmission electron microscope reveals clean and sharp interfaces without any discernible interdiffusion/reaction in the sample. The physical properties of the capacitors are vertically characterized as the parameters of memory elements. Excellent ferroelectric properties, e.g., large remnant polarization of ∼22 μC/cm2, small coercive voltage of ∼1.15 V, being fatigue-free, good retention characteristic, imply that amorphous Ni–Al is an ideal candidate for diffusion barrier for the high-density ferroelectric random access memories integrated with silicon transistor technology. [ABSTRACT FROM AUTHOR]

Bright blue-violet photoluminescence centered at 428 nm was obtained in amorphous Si-in-SiNx thin films prepared in a cyclic growth mode on cool substrates by plasma-enhanced chemical vapor deposition, in which the typical size of the silicon particles has been brought down to ∼1.80 nm and the number density amounts to 1.07×1013 cm2. A maximum external quantum efficiency over 3.0% was measured in the as-deposited samples. Time-resolved photoluminescence spectra revealed decay times within nanosecond even at room temperature, disclosing a fast recombination dynamics in this amorphous system. The excellent efficiency can be attributed to a better passivation of the silicon particles—hence, the conventional rapid thermal annealing has a negligible effect on the photoluminescence intensity—and also to an improved transparency of the film by cyclic growth. The high-efficiency, tunable wavelength and nanosecond decay time at room temperature, achieved via a low-temperature process without invoking any posttreatment, combine to make the Si-in-SiNx system a promising candidate for light-emitting nanostructures in photonic and optoelectronic applications. [ABSTRACT FROM AUTHOR]