Nanocrystalline silicon films were prepared by pulsed-laser ablation in high-purity He, Ar or Ne gas at room temperature under a deposition pressure of 10 Pa. The Raman and Xray diffraction spectra indicate that the films are nanocrystalline. Scanning electron microscopy images show that Ar or Ne gas, compared to He gas, yields smaller and more uniform-sized Si nanoparticles at the same deposition conditions, which is also confirmed by the blue-shifted and narrower peaks obtained in photoluminescence measurement. Ne gas induces the smallest and most uniform, in size, Si nanoparticles among all the three gases, which may be attributed to a more effective energy transfer between Si and Ne atoms resulting from the adjacent degree of the atomic weights.

The transport dynamics of ablated particles produced by pulsed-laser deposition in an inert gas is investigated via the Monte Carlo simulation method. The splitting mechanism of ablated particles is discussed by tracking every ablated particle with their forces, velocities and locations. The force analysis demonstrates that whether the splitting appears or not is decided by the releasing way of the driving force acting on the ablated particles. The "average" drag force, which is related to the mass and radius of the ambient gas, determines the releasing way of the driving force. Our simulated results are approximately in agreement with the previous experimental data.

a Adsorption energies and density of states for O atoms adsorption on the Ti 3 Al (0001) surface have been calculated using first-principles calculations based on density functional theory. It is found that the order of O atom adsorption on the Ti 3 Al (0001) surface is associated with the adsorption energy as well as the distance of O atoms because of the interaction. The adsorption energy mainly depends on the bond number and bond strength between O and Ti atoms, and the adsorption site with rich-Ti surface (H I and HCP Al ) is first priority. The adsorption energy decreases with the increase of the oxygen coverage because of the characteristics of the valence d-orbitals of transition metals surface. Furthermore, the density of states indicates that the hybridization peak of O and Ti atoms is mainly from the contribution of Ti 3d-and O 2p-orbitals, and the hybridization peak of O and Al atoms from the contribution of Al 2p-and O 2p-orbitals.

Nanocrystalline silicon (nc-Si) films were systematically prepared via three ways: a) laser anneal or b) thermal anneal of the amorphous silicon (α-Si) films deposited by pulsed-laser ablation (PLA) in base vacuum, c) direct PLA in high-purity Ar gas with pressure of 10 Pa. The anneal-laser fluence, thermal-anneal temperature and ablation-laser fluence thresholds corresponding to the beginning of nanoparticles formation were respectively determined by using scanning electron microscopy (SEM), Raman and X-ray diffraction (XRD) techniques. Incorporated with crystallization mechanism, energies compensated for the formation of one Si nanoparticle in the three ways were calculated approximately. The result shows that for different crystallization ways, the potential barriers during the formation of one ∼16 nm nanoparticle are on the order of 10-9 mJ.

Analysis of size effects in Pb ( Zr 0.54 Ti 0.46 ) O 3 thin film capacitors with platinum and LaNiO 3 conducting oxide electrodes Diffusion of oxygen tracer into deuterium-gas-baked Ir O x ∕ Pb ( Zr , Ti O 3 ) Pt capacitors and Pb ( Zr , Ti ) O 3 Pt films J. Appl. Phys. 98, 094107 (2005); 10.1063/1.2099508 Direct observation of region by region suppression of the switchable polarization (fatigue) in Pb(Zr,Ti)O 3 thin film capacitors with Pt electrodes Both FePt/ PbZr 0.4 Ti 0.6 O 3 ͑PZT͒ / Pt and Pt/PZT/Pt ferroelectric capacitors have been fabricated onSi substrates. It is found that up to 10 9 switching cycles, the FePt/PZT/Pt capacitor, measured at 50 kHz, with polarization decreased by 57%, is superior to the Pt/PZT/Pt capacitor by 82%, indicating that an intermetallic FePt top electrode can also improve the fatigue-resistance of a PZT capacitor. Maximum dielectric constants are 980 and 770 for PZT capacitors with FePt and Pt, respectively. This is attributed to the interface effect between PZT film and the top electrode since the interfacial capacitance of FePt/PZT is 3.5 times as large as that of Pt/PZT interface.