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The effects of plasma power on the epitaxial behavior of (Ba0.48Sr0.52)TiO3 (BST) film growth on MgO (001) substrates were examined using radio frequency magnetron sputtering with mild sputtering powers. The structure of the BST films was investigated by means of synchrotron x-ray scattering studies. Results indicate that it is feasible to control the epitaxial quality of BST films by increasing the plasma power in the range of sputtering powers between 1 and 3 W/sq cm.

The impact of a thin V insertion layer into Ta film with/without ion bombardment on Ta diffusion barrier performance in Cu metallization was studied to increase the failure temperature of Ta diffusion barrier for Cu. Results showed that the insertion of the thin V layer into the Ta film enhanced barrier characteristics substantially when the Ta/V/Ta diffusion barrier was deposited with ion bombardment.

Heteroepitaxial growth behavior of Mn-doped ZnO thin films (Zn[sub 1-x]Mn[sub x]O) on Al[sub 2]O[sub 3] (0001) substrates by pulsed laser deposition was investigated particularly as a function of Mn content (0.00<=x<=0.35) using synchrotron x-ray scattering and atomic force microscopy. The undoped ZnO film was grown epitaxially with a 30° rotation of ZnO basal planes with respect to the Al[sub 2]O[sub 3] substrate while having a small amount of grains with another epitaxial relationship, i.e., the hexagon-on-hexagon growth. A small amount of Mn doping (x=0.05) not only greatly improved the atomic alignment both in the in-plane and in the out-of-plane directions, but also led to a singly oriented film by totally suppressing the hexagon-on-hexagon growth. With further incorporation of Mn into ZnO beyond that content, the epitaxial nature again deteriorated. The superior epitaxial growth of the film with an optimum Mn content is attributed to the formation of much larger grains in it. In addition, our Mn-doped ZnO thin films showed a paramagnetic behavior. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Heteroepitaxial growth behavior of SrRuO[SUB3] /SrTiO[SUB3] (001) thin films during early stages by pulsed laser deposition was investigated using synchrotron x-ray scattering, atomic force microscopy, and high-resolution transmission electron microscopy. We find that three-dimensional (3D) SrRuO[SUB3](110) islands of ~1500 Å in diameter grow at an initial stage of growth (30 Å in thickness), in contrast to the two-dimensional layer growth previously reported in thick (3000 Å) films by off-axis sputtering. Interestingly, the 3D islands are coherently strained to the substrate, possessing a very narrow mosaic distribution of 0.007º half width at half maximum. On top of the existing well-aligned islands, poorly aligned 3D islands of much smaller sizes progressively grow, reducing the interfacial strain while maintaining the small surface roughness of 9 Å up to the film thickness of 420 Å. [ABSTRACT FROM AUTHOR]

Microstructural changes in epitaxial SrRuO[sub 3] thin films grown on SrTiO[sub 3](001) during the early stages of growth by pulsed laser deposition were studied using synchrotron x ray scattering. We find that at a very early stage of growth (<=110 Å), the film is composed of a single (110) domain only, in sharp contrast to double (110) domains reported previously for thick (>=1000 Å) films. As the film grows further (>110 Å), another, 90° rotated, (110) domain starts to form, coexisting with the original (110) domain. This domain evolution is attributed to strain relaxation, eventually resulting in significant atomic ordering in the in-plane direction. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Examines the effects of strain energy on the preferred orientation of titanium-nitrogen thin films. Application of a plasma-enhanced chemical-vapor deposition; Effect of strain energy on the overall energy of the film; Minimum number of broken bonds per unit area.

We suggest a unified decay formula for luminescence decays in light-emitting diodes by modifying the classical stretched exponential decay. From fundamental considerations we find that the stretched exponent, which is a constant in the classical stretched exponential decay, intrinsically changes with time for luminescence decays. On this basis we develop a unified decay formula by introducing a time-dependent stretched exponent. The time dependence of the stretched exponent is attributed to the lifetime dispersion of localized excitons. [ABSTRACT FROM AUTHOR]

We studied mathematical models for degradation behaviors of current and voltage in electron guns especially using oxide cathodes. We found that the current and the voltage, I(t) and V(t), follow the stretched exponential decay in oxide cathodes. On this basis, we derived a general expression for the time-dependent current–voltage relation as I(t)=p(t)V(t)δ(t), where δ(t) is a time-dependent exponent and the perveance, p(t), is a function of δ(t). The exponent δ(t) indicates the deviation of the classical Child–Langmuir relation (I=pV3/2). This deviation is attributed to the gradual change of the electron gun geometry over time. [ABSTRACT FROM AUTHOR]

We have studied the inhibition of abnormal acicular grain growth of the Ba-ferrite phase in the crystallization of Ba-ferrite films using real time synchrotron x-ray scattering, field emission scanning electron microscope, and vibrating sample magnetometer. Amorphous Ba-ferrite film on a SiO[sub 2] substrate is naturally crystallized into the abnormal acicular Ba-ferrite grains (major axis of ∼1000 nm in the in-plane direction). However, on [sup -]A1[sub 2]O[sub 3] substrate, fine grain sizes of the primary Ba-ferrite phase (∼70 nm) are obtained during crystallization. Nucleation of the α-Fe[sub 2]O[sub 3] phase on the α-A1[sub 2]O[sub 3] surface at an early stage induces the inhibition of the abnormal acicular grain growth of the Ba-ferrite phase. Because of the grain size refinement of the magnetic Ba-ferrite phase, the intrinsic coercivity of Ba-ferrite/α-A1[sub 2]O[sub 3] film enhances 4.4 kOe, much larger than that of Baferrite/SiO[sub 2] film (1.9 kOe). We suggest that the secondary α-Fe[sub 2]O[sub 3] phase act as a useful inhibitor to abnormal grain growth in Ba-ferrite films for high-density recording media. [ABSTRACT FROM AUTHOR]