Silver diffusion in cadmium sulfide single crystals

An experimental study was made of the penetration of silver by the thermal-diffusion method into cadmium sulfide. The silver was deposited on the samples by thermal evaporation in vacuum. Optical and electrical-probing methods were used to study the rates of surface and bulk diffusion at various temperatures. The temperature dependence of the diffusion coefficient was established for the purity used. After the penetration of the silver impurity, the low-resistivity ( 0.1 · cm), nonphotosensitive cadmium sulfide samples displayed high resistivity ( 10⁶-10⁸ · cm) and photosensitivity.Translated from Izvestiya VUZ. Fizika, No. 7, pp. 12–16, July, 1970.     

Formation of radiation defects in single crystals of NaCl and kcl irradiated with channeled electrons with energies 10‐50 keV

We present the results of investigations of the process of formation of F-centers in single crystals of NaCl and kCl upon exposure to 10–50 keV electrons with the incident electron beam directed at various angles to the crystallographic axes < 100> of single crystals. We showed that when the electrons are channeled, the rate of formation of F-centers increases, and the concentration of F-centers near the surface of the single crystals increases. We established a connection between the observed orientation phenomena in the formation of F-centers and the radiation dose and initial energy of the electrons. We determined characteristic angles for channeling the electrons.     

Unique features of electrical conductivity in cadmium sulfide crystals irradiated by high-neutron dosages

Irradiation of semiconductors by high-energy heavy particles leads to the formation of defect clusters. The present study will analyze the dosage dependence of dark conductivity () in high-resistance CdS single crystals upon irradiation by fast neutrons. Some parameters of defect clusters in the specimens studied are evaluated.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 19–23, February, 1984.     

Oscillator strength of electron-type color centers in KCl single crystals irradiated with electrons and protons

The absorption spectra of KCl single crystals irradiated with electrons and protons at energies of 15 and 100 keV and a particle flux ranging from 5×10¹² to 10¹⁵ cm^?2 are investigated. The absorption bands attributed to simple (F, F _a, K) and complex (M, R ₂, R ₄, N) color centers are identified in the spectra. The correlation dependences of the absorption coefficients for M, R ₂, and R ₄ centers on the absorption coefficient of F centers and the correlation dependences of the absorption coefficients for R ₂ and R ₄ centers on the absorption coefficient of M centers are established. The oscillator strengths are calculated for M, R ₂, and R ₄ color centers.     

Dynamic behavior of indium contacts with single crystals of cadmium sulfide above room temperature

Dark-current relaxation is observed with single crystals of cadmium sulfide after voltage has been applied. The kinetics of this reaction have been measured with respect to voltage and temperature. The observations are explained from the viewpoint of filling and emptying of electron traps in the contact regions of the crystals.     

Absorption saturation in oxide silicate glasses colored by cadmium sulfide selenide single crystals

Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 50, No. 1, pp. 86–90, January, 1989.     

Concentration of radiation displacement defects in BSO and BGO crystals irradiated by electrons or neutrons

This work is devoted to the calculation of the concentration of radiation displacement defects (RDD) in bismuth germanate and bismuth silicate crystals as a function of particle energy (electrons and neutrons). Energy dependencies of RDD concentrations are discussed in comparison with results for other complex oxide crystals. The obtained results show that for the case of electron irradiation the radiation hardness of BSO and BGO should be similar to other oxide crystals, but for neutrons is drastically smaller. Additionally, for the neutron irradiation, the efficiency of the production of defects in the oxide sublattice is drastically smaller than for other oxide crystals.      

Electron-phonon interactions at radiative carrier capture on deep centers in cadmium sulfide single crystals

The irigins of the halfwidths of both orange and red, as well as IR, luminescence bands in specially undoped CdS single crystals were investigated. Along with the traditional analysis of dependences of the position of peak energy of the value of halfwidths on temperature, particular attention is focused on the analysis of band shapes. The detailed comparison with theoretical results was carried out. The energies of “effective” interacting phonons, the Stokes shift values and zero-phonon line positions were obtained for all bands under investigation.     

Paramagnetic frenkel defects in irradiated alkali-haloid crystals

In the EPR spectra of γ-irradiated NaF,⁶LiF, and LiF crystals with natural content of isotopes (independent of the impurity composition), the hyperfine structure (HFS) is observed against the background of a broad band. Absorption saturation in the system of defects responsible for the HFS and the broadband occurs at widely different power levels of microwave radiation, and broad band suppression takes place at registration in quadrature. The experimentally measured intensity distribution and the number of EPR lines in the⁶LiF crystal correlate with the calculated data when the spin interaction of an unpaired electron with 14 equaivalent fluorine nuclei is taken into account. A model of major radiation-induced paramagnetic defects in the form of Frenkel pairs, in which one component (the negatively charged quasi-molecule consisting of two halogen atoms) can be responsible for the HFS and the other component (F-center) for the broad band in the EPR spectrum, is proposed.     

Creep of cadmium single crystals

The creep of cadmium single crystals has been investigated in the temperature range of 78 to 297 K. It has been shown that the transient creep of Cd single crystals is described by a time dependence of the creep strain rateå t ^–m wherem is a function of the resolved shear stress and temperature. The activation areaA* depends on the resolved shear stress,, A ^{* –r} wherer=1 for room temperature andr 1·4 for 204 and 78 K. The activation enthalpy does not practically depend on the resolved shear stress in the whole region of the resolved shear stress measured and with increasing temperature it increases roughly withT ². For temperatures above 200 K the nonconservative jog motion is proposed to be the dominant thermally activated process.The authors are very grateful to Dr. P.Kratochvíl for valuable discussions.     

Electrical, optical, and photoelectric properties of electron-irradiated indium-doped cadmium sulfide single crystals

The effect of irradiation by 1.2-MeV electrons to a dose Φ=2×10¹⁷ cm^?2 on the electrical, optical, and photoelectric properties of In-doped CdS single crystals was studied. The experimental data obtained permit one to conclude that irradiation initiates decomposition of the supersaturated In solution in CdS, with the indium atoms at the sites of the cation sublattice being expelled by cadmium interstitial atoms. New slow-recombination centers were observed to exist in the irradiated CdS: In samples, with the maxima of optical quenching of the photoconductivity lying in the region of $\lambda _{M_1 } = 0.75\mu m$ and $\lambda _{M_2 } = 1.03\mu m$ . It is suggested that the new recombination centers are related to complexes containing cadmium vacancies and indium atoms.     

Determination of defects in 6H-SiC single crystals irradiated with 20 MeV Au ions

In this paper, the determination of the defects induced by 20 MeV Au irradiations in hexagonal silicon carbide single crystals is discussed. The evolution of the irradiation-induced defects as a function of the ion fluence has been studied as a function of depth below the surface using 0.5-25 keV positron beam based Doppler annihilation-ray broadening spectrometry. Results show the detection of two different kinds of defects, depending on the ion fluence.     

Structural defects in germanium single crystals

The origin and distribution of structural defects (dislocations, small angle grain boundaries, slip lines, polycrystalline inclusions) is studied in large single crystals of germanium applied in manufacturing optical elements.