[en] Single crystalline films (SCF) of Lu₂SiO₅ (LSO) and Lu₂SiO₅:Ce (LSO:Ce) silicates with thickness of 2.5-21 μm were crystallised by liquid phase epitaxy method onto undoped LSO substrates from melt-solution based on PbO-B₂O₃ flux. The luminescence and scintillation properties of LSO and LSO:Ce SCFs were compared with the properties of a reference LSO:Ce and LYSO:Ce crystals. The light yield (LY) of LSO and LSO:Ce SCF reaches up 30 % and 145 %, respectively, of that of a reference LSO:Ce crystal under excitation by α-particles of ²⁴¹Am source (5.5 MeV). We found that the luminescence spectrum of LSO:Ce SCF is red-shifted with respect to the spectrum of a reference LSO:Ce crystal. Differences in luminescence properties of LSO:Ce SCF and single crystal are explained by the different distribution of Ce³⁺ over the Lu1 and Lu2 positions of LSO host and are also due to Pb²⁺ contamination in the former.

[en] Ion milling effects on CdTe single crystal and MOCVD p-Cd_xHg_1-xTe/GaAS multi-layer hetero-structures with thick CdTe passivation layer the technology of such diodes are considered. It was revealed that CdTe (1 μm thick) passivation layer displayed the protective properties regarding ion milling action on active p-Cd_xHg_1-xTe layer. Electrical measurements did not display the formation of any n-type layers in ion milled CdTe samples. Cathodoluminescence spectra of ion milled CdTe samples indicated some reconstruction of native defects in tellurium and cadmium sub-lattices. (orig.)

[en] Bi-doped Lu₃Al₅O₁₂ (LuAG) single crystalline films (SCFs) of thickness within 8-31 μm were grown by the liquid-phase epitaxy method onto Y₃Al₅O₁₂ (YAG) single crystal substrates using a melt solution based on a Bi₂O₃ flux. Their characteristics were compared with YAG : Bi SCFs grown at the same conditions. The concentration of Bi³⁺ ions in LuAG : Bi and YAG : Bi SCFs was varied by changing the growth temperature in the ranges 0.05-0.18 at% and 0.13-0.57 at%, respectively. The absorption, luminescence and scintillation properties of these SCFs noticeably depend on the Bi³⁺ concentration. Luminescence spectra of both LuAG : Bi and YAG : Bi SCF consist of two broad emission bands in the UV and visible (VIS) spectral ranges peaking at 4.155-4.085 eV and 2.45-2.66 eV, respectively. Both the UV and VIS luminescence show complex non-exponential decays. Under ²⁴¹Am α-particle excitation the photoelectron yield of the best performing LuAG : Bi (0.18 at%) and YAG : Bi (0.13 at%) SCFs is about 15% and 21%, respectively, of that of the reference YAP : Ce single crystal.

[en] The work is dedicated to development of new types of UV -emitting scintillators based on single crystalline films (SCF) of aluminium perovskites and garnets grown by the liquid phase epitaxy (LPE) method. The development of the following three types of UV SCF scintillators is considered in this work: i) Ce-doped SCF of Y-Lu-Al-perovskites with Ce³⁺ emission in the 360-370 nm range with a decay time of 16-17 ns; ii) Pr-doped SCF of Y-Lu-Al garnets with Pr³⁺ emission in the 300-400 nm range with a decay time of 13-17 ns; iii) La³⁺ and Sc³⁺ doped SCF of Y-Lu-Al-garnets, emitting in the 290-400 nm range due to formation of the La_Y,Lu, Sc_Y,Lu and Sc_Al centers with decay time of 250-575 ns. The results of testing the several novel UV-emitting SCFs scintillators for visualization of X-ray images at ESFR are presented. It is shown that the UV emission of the LuAG:Sc, LuAG:La and LuAG:Pr SCFs is efficient enough for conversion of X-ray to the UV light and that these scintillators can be used for improvement of the resolution of imaging detectors in synchrotron radiation applications.

[en] The peculiarities of the luminescence and energy transfer from YAG host to the emission centers formed by the Y_Al antisite defects and Ce³⁺ ions have been studied in YAG:Ce single crystals, grown from the melt by modified Bridgman method in Ar and CO₂ + H₂ atmospheres, and YAG:Ce single crystalline film, grown by liquid phase epitaxy method, using the comparative time-resolved luminescent spectroscopy under excitation by synchrotron radiation in the range of fundamental adsorption of this garnet.

[en] Peculiarities of growth of single crystalline films (SCF) of Pr³⁺ doped Y₃Al₅O₁₂ and Lu₃Al₅O₁₂ garnets and YAlO₃ and LuAlO₃ perovskites by the liquid phase epitaxy method from melt-solutions based on PbO-B₂O₃ flux as well as luminescent and scintillation properties of these SCFs were studied in this work. Dependence the intensity of the Pr³⁺ d-f and f-f-luminescence on the activator concentration and influence of Pb²⁺ flux dopant on the light yield of SCFs of the mentioned garnets and perovskites were analyzed.

[en] Intrinsic emission of complex oxides with garnet structure was studied by means of the analyses of the time-resolved luminescence spectra and decay kinetic for single crystals (SC) and single-crystalline films (SCF) of Y₃Al₅O₁₂ (YAG) and Lu₃Al₅O₁₂ (LuAG) garnets under excitation by the pulse X-ray and synchrotron radiation at 8-300 K. YAG and LuAG SC and SCF are characterized by significantly different concentration of the Y_Al and Lu_Al antisite defects (AD) due to the substantial difference in the conditions of their crystallization. For this reason, LuAG and YAG SC and SCF are very useful model objects for the study of nature of the intrinsic emission of these oxides, consisting of the excitons and AD luminescence. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

[en] The work is dedicated to the development of scintillating screens based on single crystalline films (SCF) of Ce doped Lu–Y–Al perovskites grown by the liquid phase epitaxy method. We show in this work that Lu_1−xY_xAP:Ce SCF with very good structural and optical perfection can be grown from the PbO-based flux onto YAP substrates in all range of x-values. We also found the Lu_1−xY_xAP:Ce SCF can be crystallized by LPE method from the lead free BaO–B₂O₃–BaF₂ flux onto YAP substrates in the range of x values up to 0.4 formula units. -- Highlights: ► Growth of Lu_1−xY_xAlO₃:Ce films by LPE method from PbO and BaO based fluxes. ► Comparison of the luminescent and scintillation properties of Lu_1−xY_xAP:Ce films. ► Advantages of Lu_1−xY_xAlO₃:Ce films scintillators grown from BaO based flux

[en] The paper is dedicated to studying the optical properties of YAG:Er single crystalline films (SCF) grown by liquid phase epitaxy. The absorption, cathodoluminescence and photoluminescence spectra were measured for the YAG:Er SCFs with different doping levels of Er³⁺ from 0.735 to 6.6 at%. The luminescence spectra and luminescence excitation spectra under synchrotron radiation excitation in the fundamental absorption range of the YAG and in the intrinsic f–d absorption bands of Er³⁺ ions reveal the peculiarities of energy transfer from the YAG host to the Er³⁺ ions. - Highlights: • Growth of YAG:Er single crystalline films by the liquid phase epitaxy method. • Scheme of Er³⁺ levels in YAG host. • Cooperative processes of redistribution of the Er³⁺ luminescence

[en] The work is dedicated to the development of scintillating screens based on the single crystalline films (SCF) of Ce,Tb doped Lu-based silicates, perovskites and garnets grown by the liquid phase epitaxy method. We confirm in this work the presence of the Ce → Tb energy transfer in LSO and LuAP hosts. We also show that in Ce–Tb doped LuAG SCF, the effective Tb → Ce energy transfer is observed. This results in increasing the light yield of the luminescence of double doped LuAG:Ce,Tb SCF up to 25–30% with respect to single Ce doped (Y,Lu)AG SCF counterparts at optimal ratio of Ce/Tb ions. -- Highlights: ► Growth of LSO, LuAP and LuAG films by LPE method. ► Effective Ce → Tb energy transfer in LSO, LuAP and LuAG hosts. ► Higher light yield of Ce,Tb doped LSO, LuAP and LuAG film screens