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Investigating (Ce (sub x) Zr (sub 1-x)) O2 films obtained by reactive sputtering of Ce and Zr metal targets is presented. The results suggest that the (Ce (sub x) Zr (1-x)) O2 films are potential buffer layer for HTSC films.

Investigating the fabrication of CeO2/YSZ/CeO2, textured multilayer on biaxially textured nickel substrates by reel-to-reel sol-gel dip coating process is discussed. Polefigure analysis of CeO2 films revealed cube on cube textured growth, and FWHM values of out-of-plane and in plane scan.

Reporting the deposition of pinhole-free crack-free and textured CeO2 thin films on textured Ni tapes using a reel-to-reel sol-gel dip coating process for YBCO coated conductors is presented. The pole figure analysis of CeO2 films reveals the cube-on-cube textured growth, and FWHM values of out-of-plane and in plane scan are 6.47 degree and 7.26 degree respectively.

CeO2 buffer layers for YBCO coated conductors are deposited on biaxially textured Ni substrates by a metalorganic chemical vapor deposition (MOCVD) method using a liquid source are investigated. The variables for the texture of CeO2 films were the oxygen partial pressure (P (sub O2)), deposition temperature, and time.

A study on how the microwave surface resistance of YBa2u3Oy (YBCO) thin films are affected by the crystallinity and surface roughness of CeO2 buffer on R-plane Al2O3 substrate was conducted. X-ray diffraction method was used to measure the microwave surface resistance from the microstrip line resonator's transmission characteristics. Results show that the quality of the upper layer of the YBCO is affected by the poor crystallinity of thin CeO2.

The crystal structure of [Lu.sub.2](Si[O.sub.4])O:Ce ('LSO') has two trivalent cation sites which may be occupied by [Ce.sup.3+] to form luminescence centers. Previous investigations revealed the existence of two distinct sets of [Ce.sup.3+] excitation and emission spectra and suggested that the differences in the spectra are due to differences in the crystal fields at the two lattice sites that shift the 5d levels of [Ce.sup.3+]. In the present report, we reexamine this issue and present new evidence which suggests a different interpretation. In particular, spectra measured at 13 K suggest that both lattice sites may give rise to indistinguishable excitation and emission spectra while the second set of observed spectra may arise from [Ce.sup.3+] located in interstitial sites. The evidence for the interstitial sites is a disappearance of the doublet structure in the emission spectra and a large variation in the population of the sites as a function of total cerium concentration. In addition, the results indicate that the scintillation properties of LSO are influenced by the relative population of Ce in interstitial sites compared to lattice sites as well as by differences in the transfer efficiencies to different sites.

The growth of YBa2Cu3O(7-x) (YBCO) thin films on patterned cerium oxide thin films (CeO2) deposited on yttria-stabilized zirconia and on YBCO/LaAlO3 thin films via magnetron sputtering was investigated. Specifically, the oxygen composition during patterning and YBCO growth processes were monitored using x-ray diffraction. In addition, a YBCO track with 25 ramps was also made by crossing steps in a CeO2 buffer layer.

Results concerning the relative importance of several processes which are responsible for the efficiency and speed of a scintillator are presented here. Arguments for concentrated (stoichiometric) materials are presented and illustrated in the case of Ce-pentaphosphate, ([CeP.sub.5] [O.sub.14]). The low density of this material does not make it a viable scintillator, but its remarkable simplicity and relatively easy technology make it perfect to study basic physical mechanisms of scintillation in concentrated materials. Based on studies of a series of [Ce.sub.x] [La.sub.1-x] [P.sub.5] [O.sub.14] crystals, we formulate general conclusions concerning the relative importance of the process starting with direct ionization of the emitting centers ([Ce.sup.3+]) versus long range gathering of electron-hole pairs. These conclusions provide guidance form optimizing speed and efficiency of future concentrated scintillators. in addition some peculiarities of the Ce-pentaphosphate luminescence are reported and interpreted.

A study was done on the cerium trifluoride (CeF3) scintillator using optical and ionizing radiation excitations. Results show that CeF3 is a fast and efficient scintillator. However, its efficiency is affected by the ultra fast component which is responsible for non-radiative quenching and therefore cannot be fully utilized. Nevertheless, the quenching can be eradicated which will increase the light output by 100% and greatly improve its scintillator properties.

In this paper we report on the scintillation properties of cerium doped strontium--and barium hafnate. Radioluminescence, pulse height, scintillation decay and timing spectra are presented. Radioluminescence spectra of SrHf[O.sub.3]:[Ce.sup.3+] and BaHf[O.sub.3]:[Ce.sup.3+] consist of a broad band due to [Ce.sup.3+] emission peaking at 410 nm and 400 nm, respectively. The light yield of BaHf[O.sub.3]:[Ce.sup.3+] and SrHf[O.sub.3:][Ce.sup.3+] is approximately 40 000 photons/MeV when compared to a crystal of BGO. The principal decay time constant for SrHf[O.sub.3]:[Ce.sup.3+] and BaHf[O.sub.3]:[Ce.sup.3+] is 42 and 25 ns, respectively. A timing resolution of 276 ps (FWHM) was obtained with transparent optical ceramic of SrHf[O.sub.3]:[Ce.sup.3+]. Index Terms--Ceramics, cerium compounds, hafnium compounds, scintillation detectors.

Discussing the effects of texturing and surface roughness of CeO2 layer on J (sub c) of YBCO coated conductor is presented. The grain alignment, delta phi, and surface roughness, R (sub a), of CeO2 layers are improved with increasing the thickness for both substrates of YSZ single crystal substrates and IBAD-Gd2Zr2O7 metallic substrates is concluded.

Cerium-doped lutetium oxyorthosilicate (LSO) is amongst the most promising new scintillators discovered in almost five decades, with a unique combination of important properties for x and gamma-ray spectroscopy, namely: high density, fast decay, and large light yield. LSO seems to be a prime candidate to replace BGO in PET systems. However, the practical utilization of LSO is hindered by difficulties related to crystal growth (Czochralski method) due to the high temperatures employed. A new approach has been developed using a low-temperature crystal growth technology to produce scintillating LSO crystals. Light transparent polycrystalline LSO samples of a few [mm.sup.3] in volume were grown and characterized by XRD, optical absorption, light decay measurement and gamma-ray spectral response. The properties of the new crystals compared well with high-quality crystals grown by the Czochralski method.