Absence of discontinuities in ion-channeling parameters for YBa2Cu3O72d thin films

Absence of discontinuities in ion-channeling parameters for YBa2 Cu3O7δ thin films

Terahertz emission from YBa2Cu3O7Àd thin films via bulk electric-quadrupole–magnetic-dipole optical rectification

We report the observation of terahertz emission from YBa2Cu3O72d thin films excited by 1.5-eV, 150-fs pulses in the absence of external electric or magnetic fields. This emission is characterized for optimally doped d50 films and underdoped d50.5 films, over a range of temperatures T, 4 K,T,300 K, where the films change from superconductors to correlated metals. It exhibits a pronounced 4f depe...

Polycrystalline Si thin films and devices: I. Seed selection through ion channeling II. Thin-film transistors

Part I of this thesis investigates the ."seed selection through ion channeling" process, employed to modify the grain size and crystallographic texture of polycrystalline Si thin films deposited on SiO 2. In each of the three experiments, polycrystalline Si films prepared by the low-pressure chemical-vapor deposition technique were used as the starting material. Si self-implantation, at a fixed...

Critical-state flux penetration and linear microwave vortex response in YBa2Cu3O72d films

The vortex contribution to the dc magnetic field (H) dependence of the microwave surface impedance Z̃s(H)5Rs(H)1iXs(H) of YBa2Cu3O72d thin films was measured using suspended patterned resonators. Z̃s(H) is shown to be a direct measure of the flux density B(H) enabling a very precise test of models of flux penetration. Three regimes of field-dependent behavior were observed: ~1! Initial flux penet...

Preparation and Characterization of Aluminum Nitride Thin Films with the Potential Application in Electro-Acoustic Devices

In this work, aluminum nitride (AlN) thin films with different thicknesses were deposited on quartz and  silicon  substrates  using  single  ion  beam  sputtering  technique.  The  physical  and  chemical properties  of  prepared  films  were  investigated  by  different  characterization  technique.  X-ray diffraction (XRD) spectra revealed that all of the deposited films have an amorphous str...