Photoinjection studies of ion-implantation-induced electron traps in MOS structures

Trapping centers related to P⁺ and B⁺ ions implanted in the SiO₂ layer as well as traps introduced into SiO₂ during boron implantation through the oxide into the silicon substrate have been investigated. The internal photoemission method has been used to estimate their capture cross section and total densityN _t .     

Influence of the breakdown mechanism on the behavior of lead-antimony alloys with an alternating load

For the example of Pb-Sb alloys, the influence of aging is investigated, as a function of its mechanism, on the resistance to fatigue deformation, leading to rupture along the grain boundaries. It is shown that continuous breakdown increases the cyclic life, whereas discontinuous breakdown considerably reduces it. The most effective means of suppressing discontinuous breakdown, and hence increasing the resistance to grain-boundary fatigue breakdown, is by doping with elements which reduce the mobility of the grain boundaries, such as tellurium in led. Doping with elements that facilitate discontinuous breakdown (such as As in PbSb) leads to significant reduction in the fatigue resistance.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 8, pp. 61–64, August, 1982.     

Fluorescence and phase transition of p-terphenyl crystal

The fluorescence and the excitation spectra are reported for the p-terphenyl crystal in the temperature range from 300 to 5 K. The appearance of a new band at 335 nm in the fluorescence spectrum and the large blue shift of the excitation spectrum, 1200 cm^-1, on lowering the temperature are explained by the displacive-type phase transition in a wide temperature range, 191-20 K, where the dihedral angle θ of the TP molecule increases uniformly and continuously.     

Characterization of a surface state on TiN(001)

A surface state seen in normal photoemission from TiN(001), at - 2.9 eV relative to the Fermi energy, is associated with the Δ₅ band in the bulk band structure consisting of N p_x/p_y orbitals. As TiN is somewhat ionic, there is a change in the electrostatic potential at the surface and this is large enough to pull a Tamm surface state off the Δ₅ band.     

The surface reconstructions of the (100) crystal faces of iridium,platinum and gold: I. Experimental observations and possible structural models

The structures of the reconstructed Ir(100), Pt(100) and Au(100) surfaces have been investigated. Low energy electron diffraction (LEED) patterns are analyzed and LEED intensity versus energy data are measured. A variety of structures is observed by LEED: Ir(100) exhibits a relatively simple (1 × 5) pattern; Pt(100) shows a series of closely related patterns, a typical representative of which has a $\text{(}\text{14}\text{1}\text{?1}\text{5}\text{)}$ structure; Au(100) usually exhibits a c(26 × 68) pattern, often inaccurately described in the literature as a (20 × 5) pattern. The reconstruction of Au(111) is also considered for comparison. Various plausible structural models are discussed, while laser simulation is used to lessen the number of these models. The analysis is completed in a companion paper where LEED intensity calculations are reported to determine the atomic locations.     

X-ray investigation of short-range order in the liquid eutectic alloy Bi-Cd-Sn

From an analysis of the curves of the intensity of x-ray scattering and the atomic radial distribution function, information has been obtained about the formation of a complex polystructure in a liquid Bi-Cd-Sn melt near the melting point. The hypothesis is proposed that in the most probable structure of the liquid eutectic Bi-Cd-Sn alloy, in the neighborhood of the melting point, there are microscopic orbital regions containing bismuth atoms and microscopic regions with a statistical distribution of cadmium and tin. As the temperature is raised, this atomic distribution changes, and a homogeneous atomic solution is formed.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 3, pp. 7–10, March, 1975.     

Investigation of piezoelectric properties of crystals using surface excitation of ultrasonic waves and some results for ferroelectric triglycine sulphate

The surface excitation of ultrasonic waves as a new method of investigation of piezoelectric properties of materials is suggested and experimental results specified to theZ-direction of a single crystal of triglycine sulphate (TGS) are reported. It has been found that the piezoelectric stress constant e₂₃ of TGS depends on temperatureθ as:e ₂₃=K ₂₃(θ_c?θ)^?1 whereK ₂₃=(31±0.5) As m^?2 deg andθ _c=49.6°C. The influence of an externally applied d.c. electric field has been studied in order to account for a residual excitation of ultrasonic waves in TGS at temperatures above the Curie point.     

Dynamics of lateral modes in broad aperture injection lasers

The dynamics of optical filaments in broad aperture semiconductor lasers was studied. We use the model where one longitudinal mode is taken into account. The spectrum and the instabilities of lateral modes joined with the above mentioned longitudinal mode were investigated. The structures arise due to instability of various number of lateral modes. On the background of these modes we found a new type of modulation with a frequency depending on the laser aperture width. This frequency is smaller than the electron-photon resonance one. The existence of the modulation was confirmed by experimental investigations of broad aperture laser noise spectra.     

4f-electric quadrupolar effects on the lattice constants and magnetism of RCu2Ge2 (R=rare-earths)

The temperature dependence of the lattice constants of the alloys, RCu₂Ge₂ (R=Nd, Tb, Dy, Ho and Tm) shows the existence of a lattice strain due to the alignment of the 4f-electric quadrupole at low temperatures. This strain could be related to the deviation of the Néel temperatures (T _N ) from that predicted by de Gennes scaling, thereby indicating the role of the quadrupole on the magnetism. On the other hand, in PrCu₂Ge₂, for which the enhancement ofT _N is the largest in thisR series, the lattice constants interestingly behave as if the 4f-quadrupole moment is almost quenched and the anomalous magnetism in this case is attributed to some degree of 4f-delocalisation.