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Information × Registration Number 0208U006599, 0107U009884 , R & D reports Title SID "The development of methods of modification of characterictics of light emitting structures on the base of II-VI conpounds for needs of optoelectronics and medicine" popup.stage_title Head Korsunska N.O., Registration Date 11-12-2008 Organization Institute of Semiconductor Physics of NAS of Ukraine popup.description2 Objects of investigations are epitaxial heterostructures CdZnTe/ZnTe and CdZnSe/ZnSe with quantum wells (QW) and quantum dots (QD), colloidal quantum dots CdSe in ZnS shell. Research techniques - optical, luminescent, X-ray diffraction. The method of enhancement of an integrated luminescent emission of quantum confinement structures is offered by adding a thin CdTe insert in CdZnTe QW during preparation. It is shown, that the dependencies of a luminescence intensity on temperature and on excitation level in CdSe/ZnSe heterostructures with QD are described by model of independent capture (escape) of charge carriers in QD. The analytical solution of combined equations for this model is obtained for the first time. It is shown, that the conjugation of colloidal CdSe QDs with biomolecules results in blue shift of a maximum of their emission, that can be used for registration of presence of immunoassays and allows significantly to improve the accuracy of the analysis. The mechanism of effectis is established. The method of enhancement of the changes in luminescence spectra due to conjugation of biomolecules by low-temperature annealing is offered. The effect of enhancement of emission intensity of colloidal QDs CdSe under ultraviolet illumination is revealed and its mechanism is elucidated. It is found that the annealing of superlattices CdSe/ZnSe samples with QDs at the temperatures less then 250 oС results in the increase of intensity of QD luminescence in 3,3 times. The method of enhancement of QD emission intensity is offered. It is revealed that samples with CdSe QDs are characterised by higher thermal stability than samples with CdZnSe QWs. It is found, what the increase of the content of cadmium in QWs results in the lowering of stability of characteristics under the 60Со irradiation. It is revealed, what in all heterostructures CdZnSe/ZnSe with QWs after an irradiation by 60Со with a dose 2х10^8 Rad the partial relaxation of tensile stress in capping ZnSe layers and compressive stress in QWs takes place. Is shown that the structures with QDs demonstrate a greater stability than structures with QWs. Product Description popup.authors popup.nrat_date 2020-04-02 Close