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Eu3+ doped porous nanostructured SrTiO3 films and powder fabricated by sol-gel route without using any precursor template are characterized by different morphology and phase composition. The films and the power show red and yellow luminescence with the most intensive photoluminescence (PL) bands at 612 nm and 588 nm, respectively. Raman, secondary ion mass spectrometry (SIMS), and X-ray diffraction (XRD) analysis of undoped nanostructured porous SrTiO3 films showed the presence of TiO2, SrO, and SrTiO3 phases and their components. The undoped porous SrTiO3 films are photosensitive and demonstrate resistive switching. The capacitance-voltage hysteresis loops with the width of about 6 V in the frequency range of 2 kHz—2 MHz were observed.

b) P.N. Lebedev Physical Institute, RAS, 53 Leninsky Pr., CdSe/ZnSe structures grown on n þ -GaAs(100) by molecular beam epitaxy were studied by methods of deep-level transient spectroscopy (DLTS) and cathodoluminescence (CL). In DLTS measurements, an unusual dependence of the activation energy for electron emission from CdSe layer levels on filling conditions was observed. This dependence was explained on basis of the interaction between electron charge in CdSe quantum dots (QD) and charged deep levels placed in ZnSe barriers. The existence of barriers for the electron capture by QDs was found also.Introduction In the last years, thin CdSe layers in ZnSe crystal matrix have become the most popular system to study low dimensional structures in II-VI compounds. To date there are many articles devoted to investigations of structural and optical properties of CdSe/ZnSe QDs depending on growth conditions. However to our knowledge such structures have not been studied by the very informative DLTS method yet. In particular, DLTS allows to measure offsets of conduction and valence bands in quantum well (QW) structures [1, 2] that are very important information for potential device applications. In [3], the use of combined DLTS and photoluminescence measurements allowed to estimate an energy barrier for carriers at the InAs/GaAs interface of the QDs. Investigation of an influence of deep levels around the InAs QDs on carrier capture was carried out also by DLTS [4]. In this work we present first results of current-DLTS measurements of MBE-grown CdSe/ZnSe multilayer structures.

Molecular-beam-epitaxy-grown ZnTe/CdZnTe/ZnTe and ZnSe/ZnCdSe/ZnSe strained single-quantum-well structures with non-doping layers were investigated by cathodoluminescence (CL) and deep-level transient spectroscopy (DLTS). The activation energies for deep levels in ZnTe and ZnSe buffer layers grown on GaAs were determined by the DLTS spectra. Moreover, an additional DLTS peak that depends on the quantum well (QW) parameters and correlates with the QW emission line position in the CL spectra was observed. This peak is interpreted as an emission of electrons from a ground level in the QW. Obtained DLTS and CL results were used for the estimation of the conduction band offset parameter QC.

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